0.3.4

This release fixes the build for the Linux 6.5 release candidate, and it should also fix a long-standing mmap bug in Linux 5.14 and above, which resulted in null pointer dereference. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>
Fix mmap for kernels 5.14 and above
2026-08-18 02:19:59 -07:00 · 2023-08-14 23:50:19 -03:00 · 2023-08-14 19:50:22 -03:00 · 2023-08-08 20:58:11 -03:00 · 2023-08-08 19:14:10 -03:00 · 2023-06-07 20:40:53 -03:00
19 changed files with 1571 additions and 494 deletions
@@ -497,7 +497,7 @@ static inline void apfs_init_sibling_link_key(u64 ino, u64 id,
 {
 	key->id = ino;
 	key->type = APFS_TYPE_SIBLING_LINK;
-	key->number = id; /* Only guessing */
+	key->number = id; /* Only guessing (TODO) */
 	key->name = NULL;
 }

@@ -774,17 +774,22 @@ struct apfs_xattr {
 	bool has_dstream;
 };

-#define apfs_emerg(sb, fmt, ...) apfs_msg(sb, KERN_EMERG, fmt, ##__VA_ARGS__)
-#define apfs_alert(sb, fmt, ...) apfs_msg(sb, KERN_ALERT, fmt, ##__VA_ARGS__)
-#define apfs_crit(sb, fmt, ...) apfs_msg(sb, KERN_CRIT, fmt, ##__VA_ARGS__)
-#define apfs_err(sb, fmt, ...) apfs_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
-#define apfs_warn(sb, fmt, ...) apfs_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
-#define apfs_notice(sb, fmt, ...) apfs_msg(sb, KERN_NOTICE, fmt, ##__VA_ARGS__)
-#define apfs_info(sb, fmt, ...) apfs_msg(sb, KERN_INFO, fmt, ##__VA_ARGS__)
+/*
+ * Report function name and line number for the message types that are likely
+ * to signal a bug, to make things easier for reporters. Don't do this for the
+ * common messages, there is no point and it makes the console look too busy.
+ */
+#define apfs_emerg(sb, fmt, ...) apfs_msg(sb, KERN_EMERG, __func__, __LINE__, fmt, ##__VA_ARGS__)
+#define apfs_alert(sb, fmt, ...) apfs_msg(sb, KERN_ALERT, __func__, __LINE__, fmt, ##__VA_ARGS__)
+#define apfs_crit(sb, fmt, ...) apfs_msg(sb, KERN_CRIT, __func__, __LINE__, fmt, ##__VA_ARGS__)
+#define apfs_err(sb, fmt, ...) apfs_msg(sb, KERN_ERR, __func__, __LINE__, fmt, ##__VA_ARGS__)
+#define apfs_warn(sb, fmt, ...) apfs_msg(sb, KERN_WARNING, NULL, 0, fmt, ##__VA_ARGS__)
+#define apfs_notice(sb, fmt, ...) apfs_msg(sb, KERN_NOTICE, NULL, 0, fmt, ##__VA_ARGS__)
+#define apfs_info(sb, fmt, ...) apfs_msg(sb, KERN_INFO, NULL, 0, fmt, ##__VA_ARGS__)

 #ifdef CONFIG_APFS_DEBUG
 #define ASSERT(expr)	BUG_ON(!(expr))
-#define apfs_debug(sb, fmt, ...) apfs_msg(sb, KERN_DEBUG, fmt, ##__VA_ARGS__)
+#define apfs_debug(sb, fmt, ...) apfs_msg(sb, KERN_DEBUG, __func__, __LINE__, fmt, ##__VA_ARGS__)
 #else
 #define ASSERT(expr)	((void)0)
 #define apfs_debug(sb, fmt, ...) no_printk(fmt, ##__VA_ARGS__)
@@ -807,7 +812,6 @@ extern struct apfs_query *apfs_alloc_query(struct apfs_node *node,
 					   struct apfs_query *parent);
 extern void apfs_free_query(struct apfs_query *query);
 extern int apfs_btree_query(struct super_block *sb, struct apfs_query **query);
-extern struct apfs_node *apfs_omap_read_node(struct super_block *sb, u64 id);
 extern int apfs_omap_lookup_block(struct super_block *sb, struct apfs_omap *omap,
 				  u64 id, u64 *block, bool write);
 extern int apfs_create_omap_rec(struct super_block *sb, u64 oid, u64 bno);
@@ -838,7 +842,7 @@ extern int apfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		       unsigned int flags);
 extern int apfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 		       bool excl);
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 extern int apfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
 		      struct dentry *dentry, umode_t mode, dev_t rdev);
 extern int apfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
@@ -848,6 +852,16 @@ extern int apfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 		       struct dentry *new_dentry, unsigned int flags);
 extern int apfs_create(struct user_namespace *mnt_userns, struct inode *dir,
 		       struct dentry *dentry, umode_t mode, bool excl);
+#else
+extern int apfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
+		      struct dentry *dentry, umode_t mode, dev_t rdev);
+extern int apfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
+		      struct dentry *dentry, umode_t mode);
+extern int apfs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
+		       struct dentry *old_dentry, struct inode *new_dir,
+		       struct dentry *new_dentry, unsigned int flags);
+extern int apfs_create(struct mnt_idmap *idmap, struct inode *dir,
+		       struct dentry *dentry, umode_t mode, bool excl);
 #endif

 extern int apfs_link(struct dentry *old_dentry, struct inode *dir,
@@ -871,7 +885,11 @@ extern int apfs_get_new_block(struct inode *inode, sector_t iblock,
 			      struct buffer_head *bh_result, int create);
 extern int APFS_GET_NEW_BLOCK_MAXOPS(void);
 extern int apfs_truncate(struct apfs_dstream_info *dstream, loff_t new_size);
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 20, 0)
 extern loff_t apfs_remap_file_range(struct file *src_file, loff_t off, struct file *dst_file, loff_t destoff, loff_t len, unsigned int remap_flags);
+#else
+extern int apfs_clone_file_range(struct file *src_file, loff_t off, struct file *dst_file, loff_t destoff, u64 len);
+#endif
 extern int apfs_clone_extents(struct apfs_dstream_info *dstream, u64 new_id);

 /* file.c */
@@ -894,9 +912,12 @@ extern int apfs_dstream_adj_refcnt(struct apfs_dstream_info *dstream, u32 delta)

 #if LINUX_VERSION_CODE < KERNEL_VERSION(5, 12, 0)
 extern int apfs_setattr(struct dentry *dentry, struct iattr *iattr);
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 extern int apfs_setattr(struct user_namespace *mnt_userns,
 			struct dentry *dentry, struct iattr *iattr);
+#else
+extern int apfs_setattr(struct mnt_idmap *idmap,
+			struct dentry *dentry, struct iattr *iattr);
 #endif

 extern int apfs_update_time(struct inode *inode, struct timespec64 *time, int flags);
@@ -909,16 +930,23 @@ extern int apfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 #elif LINUX_VERSION_CODE < KERNEL_VERSION(5, 12, 0)
 extern int apfs_getattr(const struct path *path, struct kstat *stat,
 			u32 request_mask, unsigned int query_flags);
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 extern int apfs_getattr(struct user_namespace *mnt_userns,
 		const struct path *path, struct kstat *stat, u32 request_mask,
 		unsigned int query_flags);
+#else
+extern int apfs_getattr(struct mnt_idmap *idmap,
+		const struct path *path, struct kstat *stat, u32 request_mask,
+		unsigned int query_flags);
 #endif

 extern int apfs_crypto_adj_refcnt(struct super_block *sb, u64 crypto_id, int delta);
 extern int APFS_CRYPTO_ADJ_REFCNT_MAXOPS(void);

-#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 13, 0)
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 3, 0)
+extern int apfs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
+extern int apfs_fileattr_set(struct mnt_idmap *idmap, struct dentry *dentry, struct fileattr *fa);
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(5, 13, 0)
 extern int apfs_fileattr_get(struct dentry *dentry, struct fileattr *fa);
 extern int apfs_fileattr_set(struct user_namespace *mnt_userns, struct dentry *dentry, struct fileattr *fa);
 #endif
@@ -935,8 +963,7 @@ extern int apfs_read_snap_meta_key(void *raw, int size, struct apfs_key *key);
 extern int apfs_read_omap_snap_key(void *raw, int size, struct apfs_key *key);

 /* message.c */
-extern __printf(3, 4)
-void apfs_msg(struct super_block *sb, const char *prefix, const char *fmt, ...);
+extern __printf(5, 6) void apfs_msg(struct super_block *sb, const char *prefix, const char *func, int line, const char *fmt, ...);

 /* node.c */
 extern struct apfs_node *apfs_read_node(struct super_block *sb, u64 oid,
@@ -35,13 +35,17 @@ static int apfs_child_from_query(struct apfs_query *query, u64 *child)
 	if (query->flags & APFS_QUERY_CAT && apfs_is_sealed(sb)) {
 		struct apfs_btn_index_node_val *index_val = NULL;

-		if (query->len != sizeof(*index_val))
+		if (query->len != sizeof(*index_val)) {
+			apfs_err(sb, "bad sealed index value length (%d)", query->len);
 			return -EFSCORRUPTED;
+		}
 		index_val = (struct apfs_btn_index_node_val *)(raw + query->off);
 		*child = le64_to_cpu(index_val->binv_child_oid) + apfs_catalog_base_oid(query);
 	} else {
-		if (query->len != 8) /* The data on a nonleaf node is the child id */
+		if (query->len != 8) { /* The data on a nonleaf node is the child id */
+			apfs_err(sb, "bad index value length (%d)", query->len);
 			return -EFSCORRUPTED;
+		}
 		*child = le64_to_cpup((__le64 *)(raw + query->off));
 	}
 	return 0;
@@ -190,8 +194,11 @@ int apfs_omap_lookup_block(struct super_block *sb, struct apfs_omap *omap,
 	query->flags |= APFS_QUERY_OMAP;

 	ret = apfs_btree_query(sb, &query);
-	if (ret)
+	if (ret) {
+		if (ret != -ENODATA)
+			apfs_err(sb, "query failed for oid 0x%llx, xid 0x%llx", id, apfs_mounted_xid(sb));
 		goto fail;
+	}

 	ret = apfs_omap_map_from_query(query, &map);
 	if (ret) {
@@ -211,6 +218,7 @@ int apfs_omap_lookup_block(struct super_block *sb, struct apfs_omap *omap,

 		new_bh = apfs_read_object_block(sb, *block, write, preserve);
 		if (IS_ERR(new_bh)) {
+			apfs_err(sb, "CoW failed for oid 0x%llx, xid 0x%llx", id, apfs_mounted_xid(sb));
 			ret = PTR_ERR(new_bh);
 			goto fail;
 		}
@@ -225,6 +233,8 @@ int apfs_omap_lookup_block(struct super_block *sb, struct apfs_omap *omap,
 			ret = apfs_btree_insert(query, &key, sizeof(key), &val, sizeof(val));
 		else
 			ret = apfs_btree_replace(query, &key, sizeof(key), &val, sizeof(val));
+		if (ret)
+			apfs_err(sb, "CoW omap update failed (oid 0x%llx, xid 0x%llx)", id, apfs_mounted_xid(sb));

 		*block = new_bh->b_blocknr;
 		brelse(new_bh);
@@ -265,8 +275,10 @@ int apfs_create_omap_rec(struct super_block *sb, u64 oid, u64 bno)
 	query->flags |= APFS_QUERY_OMAP;

 	ret = apfs_btree_query(sb, &query);
-	if (ret && ret != -ENODATA)
+	if (ret && ret != -ENODATA) {
+		apfs_err(sb, "query failed for oid 0x%llx, bno 0x%llx", oid, bno);
 		goto fail;
+	}

 	raw_key.ok_oid = cpu_to_le64(oid);
 	raw_key.ok_xid = cpu_to_le64(nxi->nx_xid);
@@ -276,8 +288,10 @@ int apfs_create_omap_rec(struct super_block *sb, u64 oid, u64 bno)

 	ret = apfs_btree_insert(query, &raw_key, sizeof(raw_key),
 				&raw_val, sizeof(raw_val));
-	if (ret)
+	if (ret) {
+		apfs_err(sb, "insertion failed for oid 0x%llx, bno 0x%llx", oid, bno);
 		goto fail;
+	}

 	apfs_omap_cache_save(omap, oid, bno);

@@ -311,13 +325,23 @@ int apfs_delete_omap_rec(struct super_block *sb, u64 oid)
 	query->flags |= APFS_QUERY_OMAP;

 	ret = apfs_btree_query(sb, &query);
-	if (ret == -ENODATA)
+	if (ret == -ENODATA) {
+		apfs_err(sb, "nonexistent record (oid 0x%llx)", oid);
 		ret = -EFSCORRUPTED;
-	if (!ret)
-		ret = apfs_btree_remove(query);
-	if (!ret)
-		apfs_omap_cache_delete(omap, oid);
+		goto fail;
+	}
+	if (ret) {
+		apfs_err(sb, "query failed (oid 0x%llx)", oid);
+		goto fail;
+	}
+	ret = apfs_btree_remove(query);
+	if (ret) {
+		apfs_err(sb, "removal failed (oid 0x%llx)", oid);
+		goto fail;
+	}
+	apfs_omap_cache_delete(omap, oid);

+fail:
 	apfs_free_query(query);
 	return ret;
 }
@@ -409,8 +433,10 @@ static int apfs_query_set_before_first(struct super_block *sb, struct apfs_query

 		/* Now go a level deeper */
 		node = apfs_read_node(sb, child_id, storage, false /* write */);
-		if (IS_ERR(node))
+		if (IS_ERR(node)) {
+			apfs_err(sb, "failed to read child 0x%llx of node 0x%llx", child_id, (*query)->node->object.oid);
 			return PTR_ERR(node);
+		}

 		parent = *query;
 		*query = apfs_alloc_query(node, parent);
@@ -422,7 +448,7 @@ static int apfs_query_set_before_first(struct super_block *sb, struct apfs_query
 		node = NULL;
 	}

-	apfs_alert(sb, "b-tree is corrupted");
+	apfs_err(sb, "btree is too high");
 	return -EFSCORRUPTED;
 }

@@ -455,7 +481,7 @@ next_node:
 		 * forever if the filesystem is damaged. 12 should be more
 		 * than enough to map every block.
 		 */
-		apfs_alert(sb, "b-tree is corrupted");
+		apfs_err(sb, "btree is too high");
 		return -EFSCORRUPTED;
 	}

@@ -466,8 +492,10 @@ next_node:
 		 * let the query give up at the root node.
 		 */
 		err = apfs_query_set_before_first(sb, query);
-		if (err)
+		if (err) {
+			apfs_err(sb, "failed to set before the first record");
 			return err;
+		}
 		return -ENODATA;
 	} else if (err == -EAGAIN) {
 		if (!(*query)->parent) /* We are at the root of the tree */
@@ -494,8 +522,10 @@ next_node:

 	/* Now go a level deeper and search the child */
 	node = apfs_read_node(sb, child_id, storage, false /* write */);
-	if (IS_ERR(node))
+	if (IS_ERR(node)) {
+		apfs_err(sb, "failed to read node 0x%llx", child_id);
 		return PTR_ERR(node);
+	}

 	if (node->object.oid != child_id)
 		apfs_debug(sb, "corrupt b-tree");
@@ -515,28 +545,6 @@ next_node:
 	goto next_node;
 }

-/**
- * apfs_omap_read_node - Find and read a node from a b-tree
- * @sb: filesystem superblock
- * @id: id for the seeked node
- *
- * Returns NULL is case of failure, otherwise a pointer to the resulting
- * apfs_node structure.
- */
-struct apfs_node *apfs_omap_read_node(struct super_block *sb, u64 id)
-{
-	struct apfs_node *result;
-
-	result = apfs_read_node(sb, id, APFS_OBJ_VIRTUAL, false /* write */);
-	if (IS_ERR(result))
-		return result;
-
-	if (result->object.oid != id)
-		apfs_debug(sb, "corrupt b-tree");
-
-	return result;
-}
-
 /**
 * apfs_query_join_transaction - Add the found node to the current transaction
 * @query: query that found the node
@@ -556,8 +564,10 @@ int apfs_query_join_transaction(struct apfs_query *query)
 	ASSERT(!apfs_node_is_root(node));

 	node = apfs_read_node(sb, oid, storage, true /* write */);
-	if (IS_ERR(node))
+	if (IS_ERR(node)) {
+		apfs_err(sb, "Cow failed for node 0x%llx", oid);
 		return PTR_ERR(node);
+	}
 	apfs_node_free(query->node);
 	query->node = node;

@@ -665,18 +675,20 @@ static int apfs_query_refresh(struct apfs_query *old_query)
 	 * which are only expected when large inline xattr values are involved.
 	 */
 	if ((old_query->flags & APFS_QUERY_TREE_MASK) != APFS_QUERY_CAT) {
-		apfs_warn(sb, "attempt to refresh a non-catalog query");
+		apfs_err(sb, "non-catalog query");
 		return -EFSCORRUPTED;
 	}
 	if (!apfs_node_is_leaf(node)) {
-		apfs_warn(sb, "attempt to refresh a non-leaf query");
+		apfs_err(sb, "non-leaf query");
 		return -EFSCORRUPTED;
 	}

 	/* Build a new query that points exactly to the same key */
 	err = apfs_read_cat_key(raw + old_query->key_off, old_query->key_len, &new_key, hashed);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to read the key");
 		return err;
+	}
 	new_query = apfs_alloc_query(APFS_SB(sb)->s_cat_root, NULL /* parent */);
 	if (!new_query)
 		return -ENOMEM;
@@ -684,8 +696,10 @@ static int apfs_query_refresh(struct apfs_query *old_query)
 	new_query->flags = APFS_QUERY_CAT | APFS_QUERY_EXACT;

 	err = apfs_btree_query(sb, &new_query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to rerun");
 		goto fail;
+	}

 	/* Set the original query flags and key on the new query */
 	for (ancestor = new_query; ancestor; ancestor = ancestor->parent) {
@@ -739,6 +753,7 @@ int apfs_btree_insert(struct apfs_query *query, void *key, int key_len,
 		      void *val, int val_len)
 {
 	struct apfs_node *node = query->node;
+	struct super_block *sb = node->object.sb;
 	struct apfs_btree_node_phys *node_raw;
 	int err;

@@ -748,8 +763,10 @@ int apfs_btree_insert(struct apfs_query *query, void *key, int key_len,
 					    key_len, val_len);

 	err = apfs_query_join_transaction(query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "query join failed");
 		return err;
+	}

 again:
 	node = query->node;
@@ -760,18 +777,23 @@ again:
 	if (err == -ENOSPC) {
 		if (!query->parent && !apfs_node_is_root(node)) {
 			err = apfs_query_refresh(query);
-			if (err)
+			if (err) {
+				apfs_err(sb, "query refresh failed");
 				return err;
+			}
 			if (node->records == 1) {
 				/* The new record just won't fit in the node */
 				return apfs_create_single_rec_node(query, key, key_len, val, val_len);
 			}
 		}
 		err = apfs_node_split(query);
-		if (err)
+		if (err) {
+			apfs_err(sb, "node split failed");
 			return err;
+		}
 		goto again;
 	} else if (err) {
+		apfs_err(sb, "node record insertion failed");
 		return err;
 	}

@@ -779,6 +801,8 @@ again:
 	if (query->parent && query->index == 0) {
 		err = apfs_btree_replace(query->parent, key, key_len,
 					 NULL /* val */, 0 /* val_len */);
+		if (err)
+			apfs_err(sb, "parent update failed");
 	}
 	return err;
 }
@@ -792,6 +816,7 @@ again:
 int apfs_btree_remove(struct apfs_query *query)
 {
 	struct apfs_node *node = query->node;
+	struct super_block *sb = node->object.sb;
 	struct apfs_btree_node_phys *node_raw;
 	int later_entries = node->records - query->index - 1;
 	int err;
@@ -804,8 +829,10 @@ int apfs_btree_remove(struct apfs_query *query)
 		apfs_btree_change_node_count(query, -1 /* change */);

 	err = apfs_query_join_transaction(query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "query join failed");
 		return err;
+	}

 	node = query->node;
 	node_raw = (void *)query->node->object.data;
@@ -834,8 +861,10 @@ int apfs_btree_remove(struct apfs_query *query)

 		err = apfs_btree_replace(query->parent, key, first_key_len,
 					 NULL /* val */, 0 /* val_len */);
-		if (err)
+		if (err) {
+			apfs_err(sb, "parent update failed");
 			return err;
+		}
 	}

 	/* Remove the entry from the table of contents */
@@ -902,8 +931,10 @@ int apfs_btree_replace(struct apfs_query *query, void *key, int key_len,
 	}

 	err = apfs_query_join_transaction(query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "query join failed");
 		return err;
+	}

 again:
 	node = query->node;
@@ -914,8 +945,10 @@ again:
 	if (key && query->parent && query->index == 0) {
 		err = apfs_btree_replace(query->parent, key, key_len,
 					 NULL /* val */, 0 /* val_len */);
-		if (err)
+		if (err) {
+			apfs_err(sb, "parent update failed");
 			return err;
+		}
 	}

 	err = apfs_node_replace(query, key, key_len, val, val_len);
@@ -927,12 +960,16 @@ again:
 				return -EFSCORRUPTED;
 			}
 			err = apfs_query_refresh(query);
-			if (err)
+			if (err) {
+				apfs_err(sb, "query refresh failed");
 				return err;
+			}
 		}
 		err = apfs_node_split(query);
-		if (err)
+		if (err) {
+			apfs_err(sb, "node split failed");
 			return err;
+		}
 		goto again;
 	}
 	return err;
@@ -36,8 +36,11 @@ static inline void *kvmalloc(size_t size, gfp_t flags)

 #endif /* LINUX_VERSION_CODE < KERNEL_VERSION(4, 12, 0) */

-/* maximum size of compressed data currently supported */
-#define MAX_FBUF_SIZE		(128 * 1024 * 1024)
+/*
+ * Maximum size of compressed data currently supported. This is getting too
+ * big already. TODO: avoid vmalloc().
+ */
+#define MAX_FBUF_SIZE		(256 * 1024 * 1024)

 struct apfs_compress_file_data {
 	struct apfs_compress_hdr hdr;
@@ -47,6 +50,7 @@ struct apfs_compress_file_data {
 	ssize_t bufblk;
 	size_t bufsize;
 	struct mutex mtx;
+	struct super_block *sb;
 };

 static inline int apfs_compress_is_rsrc(u32 algo)
@@ -77,6 +81,7 @@ static inline bool apfs_compress_is_supported(u32 algo)

 static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 {
+	struct super_block *sb = inode->i_sb;
 	struct apfs_compress_file_data *fd;
 	ssize_t res;
 	u8 *tmp = NULL, *cdata;
@@ -89,10 +94,13 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 	if(!fd)
 		return -ENOMEM;
 	mutex_init(&fd->mtx);
+	fd->sb = sb;

 	res = ____apfs_xattr_get(inode, APFS_XATTR_NAME_COMPRESSED, &fd->hdr, sizeof(fd->hdr), 0);
-	if(res != sizeof(fd->hdr))
+	if(res != sizeof(fd->hdr)) {
+		apfs_err(sb, "decmpfs header read failed");
 		goto fail;
+	}

 	if(!apfs_compress_is_supported(le32_to_cpu(fd->hdr.algo))) {
 		res = -EOPNOTSUPP;
@@ -106,11 +114,15 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 		fd->bufblk = -1;

 		res = ____apfs_xattr_get(inode, APFS_XATTR_NAME_RSRC_FORK, NULL, 0, 0);
-		if(res < 0)
+		if(res < 0) {
+			apfs_err(sb, "fork size read failed");
 			goto fail;
+		}

-		if(res > MAX_FBUF_SIZE)
+		if(res > MAX_FBUF_SIZE) {
+			apfs_err(sb, "fork too big");
 			goto fail_enomem;
+		}

 		fd->size = res;
 		fd->data = kvmalloc(res, GFP_KERNEL);
@@ -118,11 +130,15 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 			goto fail_enomem;

 		res = ____apfs_xattr_get(inode, APFS_XATTR_NAME_RSRC_FORK, fd->data, fd->size, 1);
-		if(res != fd->size)
+		if(res != fd->size) {
+			apfs_err(sb, "fork read failed");
 			goto fail;
+		}
 	} else {
-		if(le64_to_cpu(fd->hdr.size) > MAX_FBUF_SIZE)
+		if(le64_to_cpu(fd->hdr.size) > MAX_FBUF_SIZE) {
+			apfs_err(sb, "decmpfs too big");
 			goto fail_enomem;
+		}

 		fd->size = le64_to_cpu(fd->hdr.size);
 		fd->data = kvmalloc(le64_to_cpu(fd->hdr.size), GFP_KERNEL);
@@ -130,11 +146,15 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 			goto fail_enomem;

 		res = ____apfs_xattr_get(inode, APFS_XATTR_NAME_COMPRESSED, NULL, 0, 0);
-		if(res < sizeof(fd->hdr) + 1)
+		if(res < sizeof(fd->hdr) + 1) {
+			apfs_err(sb, "decmpfs size read failed");
 			goto fail;
+		}
 		csize = res - sizeof(fd->hdr);
-		if(res > MAX_FBUF_SIZE)
+		if(res > MAX_FBUF_SIZE) {
+			apfs_err(sb, "decmpfs too big");
 			goto fail_enomem;
+		}

 		tmp = kvmalloc(res, GFP_KERNEL);
 		if(!tmp)
@@ -142,26 +162,36 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 		cdata = tmp + sizeof(fd->hdr);

 		res = ____apfs_xattr_get(inode, APFS_XATTR_NAME_COMPRESSED, tmp, csize + sizeof(fd->hdr), 1);
-		if(res != csize + sizeof(fd->hdr))
+		if(res != csize + sizeof(fd->hdr)) {
+			apfs_err(sb, "decmpfs read failed");
 			goto fail;
+		}

 		switch(le32_to_cpu(fd->hdr.algo)) {
 		case APFS_COMPRESS_ZLIB_ATTR:
 			if(cdata[0] == 0x78 && csize >= 2) {
 				res = zlib_inflate_blob(fd->data, fd->size, cdata + 2, csize - 2);
-				if(res != fd->size)
+				if(res != fd->size) {
+					apfs_err(sb, "zlib attr read failed");
 					goto fail;
+				}
 			} else if((cdata[0] & 0x0F) == 0x0F) {
-				if(csize - 1 != fd->size)
+				if(csize - 1 != fd->size) {
+					apfs_err(sb, "zlib attr read failed");
 					goto fail_einval;
+				}
 				memcpy(fd->data, cdata + 1, csize - 1);
-			} else
+			} else {
+				apfs_err(sb, "zlib attr read failed");
 				goto fail_einval;
+			}
 			break;
 		case APFS_COMPRESS_LZVN_ATTR:
 			if(cdata[0] == 0x06) {
-				if(csize - 1 != fd->size)
+				if(csize - 1 != fd->size) {
+					apfs_err(sb, "lzvn attr read failed");
 					goto fail_einval;
+				}
 				memcpy(fd->data, cdata + 1, csize - 1);
 			} else {
 				lzvn_decoder_state dstate = {0};
@@ -171,45 +201,60 @@ static int apfs_compress_file_open(struct inode *inode, struct file *filp)
 				dstate.dst = dstate.dst_begin = fd->data;
 				dstate.dst_end = dstate.dst + fd->size;
 				lzvn_decode(&dstate);
-				if(dstate.dst != fd->data + fd->size)
+				if(dstate.dst != fd->data + fd->size) {
+					apfs_err(sb, "lzvn attr read failed");
 					goto fail_einval;
+				}
 			}
 			break;
 		case APFS_COMPRESS_LZBITMAP_ATTR:
 			if(cdata[0] == 0x5a) {
 				size_t out_len;
 				res = zbm_decompress(fd->data, fd->size, cdata, csize, &out_len);
-				if(res < 0)
+				if(res < 0) {
+					apfs_err(sb, "lzbitmap attr read failed");
 					goto fail;
-				if(out_len != fd->size)
+				}
+				if(out_len != fd->size) {
+					apfs_err(sb, "lzbitmap attr read failed");
 					goto fail_einval;
+				}
 			} else if((cdata[0] & 0x0F) == 0x0F) {
-				if(csize - 1 != fd->size)
+				if(csize - 1 != fd->size) {
+					apfs_err(sb, "lzbitmap attr read failed");
 					goto fail_einval;
+				}
 				memcpy(fd->data, cdata + 1, csize - 1);
 			} else {
+				apfs_err(sb, "lzbitmap attr read failed");
 				goto fail_einval;
 			}
 			break;
 		case APFS_COMPRESS_LZFSE_ATTR:
 			if(cdata[0] == 0x62 && csize >= 2) {
 				res = lzfse_decode_buffer(fd->data, fd->size, cdata, csize, NULL);
-				if(res != fd->size)
+				if(res != fd->size) {
+					apfs_err(sb, "lzfse attr read failed");
 					/* Could be ENOMEM too... */
 					goto fail_einval;
+				}
 			} else {
 				/*
 				 * I've never encountered this, but I assume
 				 * it's like the resource version.
 				 */
-				if(csize - 1 != fd->size)
+				if(csize - 1 != fd->size) {
+					apfs_err(sb, "lzfse attr read failed");
 					goto fail_einval;
+				}
 				memcpy(fd->data, cdata + 1, csize - 1);
 			}
 			break;
 		case APFS_COMPRESS_PLAIN_ATTR:
-			if(csize - 1 != fd->size)
+			if(csize - 1 != fd->size) {
+				apfs_err(sb, "plain attr read failed");
 				goto fail_einval;
+			}
 			memcpy(fd->data, cdata + 1, csize - 1);
 			break;
 		default:
@@ -242,6 +287,7 @@ fail:

 static ssize_t apfs_compress_file_read_block(struct apfs_compress_file_data *fd, char __user *buf, size_t size, loff_t off)
 {
+	struct super_block *sb = fd->sb;
 	u32 doffs = 0, coffs;
 	loff_t block;
 	u8 *cdata, *tmp = fd->buf;
@@ -262,14 +308,20 @@ static ssize_t apfs_compress_file_read_block(struct apfs_compress_file_data *fd,
 			struct apfs_compress_rsrc_hdr *hdr = fd->data;
 			struct apfs_compress_rsrc_data *cd = NULL;

-			if(fd->size < sizeof(*hdr))
+			if(fd->size < sizeof(*hdr)) {
+				apfs_err(sb, "resource header doesn't fit");
 				return -EINVAL;
+			}
 			doffs = be32_to_cpu(hdr->data_offs);
-			if(doffs >= fd->size || fd->size - doffs < sizeof(*cd))
+			if(doffs >= fd->size || fd->size - doffs < sizeof(*cd)) {
+				apfs_err(sb, "invalid data header offset in resource");
 				return -EINVAL;
+			}
 			cd = fd->data + doffs;
-			if(fd->size - doffs - sizeof(*cd) < sizeof(cd->block[0]) * (size_t)le32_to_cpu(cd->num))
+			if(fd->size - doffs - sizeof(*cd) < sizeof(cd->block[0]) * (size_t)le32_to_cpu(cd->num)) {
+				apfs_err(sb, "resource data header won't fit");
 				return -EINVAL;
+			}

 			if(block >= le32_to_cpu(cd->num))
 				return 0;
@@ -283,8 +335,10 @@ static ssize_t apfs_compress_file_read_block(struct apfs_compress_file_data *fd,
 		} else {
 			__le32 *block_offs = fd->data + doffs;

-			if((size_t)fd->size < sizeof(*block_offs) * ((size_t)block + 2))
+			if((size_t)fd->size < sizeof(*block_offs) * ((size_t)block + 2)) {
+				apfs_err(sb, "resource data header won't fit");
 				return -EINVAL;
+			}

 			bsize = le64_to_cpu(fd->hdr.size) - block * APFS_COMPRESS_BLOCK;
 			if(bsize > APFS_COMPRESS_BLOCK)
@@ -293,22 +347,28 @@ static ssize_t apfs_compress_file_read_block(struct apfs_compress_file_data *fd,
 			coffs = le32_to_cpu(block_offs[block]);
 			csize = le32_to_cpu(block_offs[block + 1]) - coffs;
 		}
-		if(coffs >= fd->size - doffs || fd->size - doffs - coffs < csize || csize > APFS_COMPRESS_BLOCK + 1)
+		if(coffs >= fd->size - doffs || fd->size - doffs - coffs < csize || csize > APFS_COMPRESS_BLOCK + 1) {
+			apfs_err(sb, "invalid block size/offset in resource");
 			return -EINVAL;
+		}
 		cdata = fd->data + doffs + coffs;

 		switch(le32_to_cpu(fd->hdr.algo)) {
 		case APFS_COMPRESS_ZLIB_RSRC:
 			if(cdata[0] == 0x78 && csize >= 2) {
 				res = zlib_inflate_blob(tmp, bsize, cdata + 2, csize - 2);
-				if(res <= 0)
+				if(res <= 0) {
+					apfs_err(sb, "zlib rsrc read failed");
 					return res;
+				}
 				bsize = res;
 			} else if((cdata[0] & 0x0F) == 0x0F) {
 				memcpy(tmp, &cdata[1], csize - 1);
 				bsize = csize - 1;
-			} else
+			} else {
+				apfs_err(sb, "zlib rsrc read failed");
 				return -EINVAL;
+			}
 			break;
 		case APFS_COMPRESS_LZVN_RSRC:
 			if(cdata[0] == 0x06) {
@@ -328,21 +388,26 @@ static ssize_t apfs_compress_file_read_block(struct apfs_compress_file_data *fd,
 		case APFS_COMPRESS_LZBITMAP_RSRC:
 			if(cdata[0] == 0x5a) {
 				res = zbm_decompress(tmp, bsize, cdata, csize, &bsize);
-				if(res < 0)
+				if(res < 0) {
+					apfs_err(sb, "lzbitmap rsrc read failed");
 					return res;
+				}
 			} else if((cdata[0] & 0x0F) == 0x0F) {
 				memcpy(tmp, &cdata[1], csize - 1);
 				bsize = csize - 1;
 			} else {
+				apfs_err(sb, "lzbitmap rsrc read failed");
 				return -EINVAL;
 			}
 			break;
 		case APFS_COMPRESS_LZFSE_RSRC:
 			if(cdata[0] == 0x62 && csize >= 2) {
 				res = lzfse_decode_buffer(tmp, bsize, cdata, csize, NULL);
-				if(res == 0)
+				if(res == 0) {
+					apfs_err(sb, "lzfse rsrc read failed");
 					/* Could be ENOMEM too... */
 					return -EINVAL;
+				}
 				bsize = res;
 			} else {
 				/* cdata[0] == 0xff, apparently */
@@ -436,8 +501,10 @@ int apfs_compress_get_size(struct inode *inode, loff_t *size)

 	if(res < 0)
 		return res;
-	if(res != sizeof(hdr))
+	if(res != sizeof(hdr)) {
+		apfs_err(inode->i_sb, "decmpfs header read failed");
 		return 1;
+	}

 	if(!apfs_compress_is_supported(le32_to_cpu(hdr.algo)))
 		return 1;
@@ -1,5 +1,5 @@
 PACKAGE_NAME="linux-apfs-rw"
-PACKAGE_VERSION="0.3.1"
+PACKAGE_VERSION="0.3.4"

 BUILT_MODULE_NAME[0]="apfs"
 DEST_MODULE_LOCATION[0]="/extra"
@@ -42,8 +42,10 @@ static vm_fault_t apfs_page_mkwrite(struct vm_fault *vmf)
 	apfs_inode_join_transaction(sb, inode);

 	err = apfs_inode_create_exclusive_dstream(inode);
-	if (err)
+	if (err) {
+		apfs_err(sb, "dstream creation failed for ino 0x%llx", apfs_ino(inode));
 		goto out_abort;
+	}

 	lock_page(page);
 	wait_for_stable_page(page);
@@ -77,8 +79,10 @@ static vm_fault_t apfs_page_mkwrite(struct vm_fault *vmf)
 	unlock_page(page); /* XXX: race? */

 	err = block_page_mkwrite(vma, vmf, apfs_get_new_block);
-	if (err)
+	if (err) {
+		apfs_err(sb, "mkwrite failed for ino 0x%llx", apfs_ino(inode));
 		goto out_abort;
+	}
 	set_page_dirty(page);

 	/* An immediate commit would leave the page unlocked */
@@ -141,8 +145,16 @@ const struct file_operations apfs_file_operations = {
 	.open			= generic_file_open,
 	.fsync			= apfs_fsync,
 	.unlocked_ioctl		= apfs_file_ioctl,
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 3, 0)
 	.copy_file_range	= generic_copy_file_range,
+#endif
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 20, 0)
 	.remap_file_range	= apfs_remap_file_range,
+#else
+	.clone_file_range	= apfs_clone_file_range,
+#endif
 };

 #if LINUX_VERSION_CODE == KERNEL_VERSION(5, 3, 0)
@@ -81,8 +81,10 @@ int apfs_keycmp(struct apfs_key *k1, struct apfs_key *k2)
 */
 int apfs_read_cat_key(void *raw, int size, struct apfs_key *key, bool hashed)
 {
-	if (size < sizeof(struct apfs_key_header))
+	if (size < sizeof(struct apfs_key_header)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	key->id = apfs_cat_cnid((struct apfs_key_header *)raw);
 	key->type = apfs_cat_type((struct apfs_key_header *)raw);

@@ -92,6 +94,7 @@ int apfs_read_cat_key(void *raw, int size, struct apfs_key *key, bool hashed)
 			if (size < sizeof(struct apfs_drec_hashed_key) + 1 ||
 			    *((char *)raw + size - 1) != 0) {
 				/* Filename must have NULL-termination */
+				apfs_err(NULL, "invalid drec key (%d)", size);
 				return -EFSCORRUPTED;
 			}
 			/* Name length is not used in key comparisons, only the hash */
@@ -103,6 +106,7 @@ int apfs_read_cat_key(void *raw, int size, struct apfs_key *key, bool hashed)
 			if (size < sizeof(struct apfs_drec_key) + 1 ||
 			    *((char *)raw + size - 1) != 0) {
 				/* Filename must have NULL-termination */
+				apfs_err(NULL, "invalid drec key (%d)", size);
 				return -EFSCORRUPTED;
 			}
 			/* There's no hash */
@@ -114,21 +118,26 @@ int apfs_read_cat_key(void *raw, int size, struct apfs_key *key, bool hashed)
 		if (size < sizeof(struct apfs_xattr_key) + 1 ||
 		    *((char *)raw + size - 1) != 0) {
 			/* xattr name must have NULL-termination */
+			apfs_err(NULL, "invalid xattr key (%d)", size);
 			return -EFSCORRUPTED;
 		}
 		key->number = 0;
 		key->name = ((struct apfs_xattr_key *)raw)->name;
 		break;
 	case APFS_TYPE_FILE_EXTENT:
-		if (size != sizeof(struct apfs_file_extent_key))
+		if (size != sizeof(struct apfs_file_extent_key)) {
+			apfs_err(NULL, "bad key length (%d)", size);
 			return -EFSCORRUPTED;
+		}
 		key->number = le64_to_cpu(
 			((struct apfs_file_extent_key *)raw)->logical_addr);
 		key->name = NULL;
 		break;
 	case APFS_TYPE_SIBLING_LINK:
-		if (size != sizeof(struct apfs_sibling_link_key))
+		if (size != sizeof(struct apfs_sibling_link_key)) {
+			apfs_err(NULL, "bad key length (%d)", size);
 			return -EFSCORRUPTED;
+		}
 		key->number = le64_to_cpu(
 			((struct apfs_sibling_link_key *)raw)->sibling_id);
 		key->name = NULL;
@@ -146,8 +155,10 @@ int apfs_read_fext_key(void *raw, int size, struct apfs_key *key)
 {
 	struct apfs_fext_tree_key *raw_key;

-	if (size != sizeof(*raw_key))
+	if (size != sizeof(*raw_key)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	raw_key = raw;

 	key->id = le64_to_cpu(raw_key->private_id);
@@ -169,8 +180,10 @@ int apfs_read_free_queue_key(void *raw, int size, struct apfs_key *key)
 {
 	struct apfs_spaceman_free_queue_key *raw_key;

-	if (size < sizeof(struct apfs_spaceman_free_queue_key))
+	if (size < sizeof(struct apfs_spaceman_free_queue_key)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	raw_key = raw;

 	key->id = le64_to_cpu(raw_key->sfqk_xid);
@@ -191,8 +204,10 @@ int apfs_read_free_queue_key(void *raw, int size, struct apfs_key *key)
 */
 int apfs_read_omap_key(void *raw, int size, struct apfs_key *key)
 {
-	if (size < sizeof(struct apfs_omap_key))
+	if (size < sizeof(struct apfs_omap_key)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}

 	key->id = le64_to_cpu(((struct apfs_omap_key *)raw)->ok_oid);
 	key->type = 0;
@@ -212,8 +227,10 @@ int apfs_read_omap_key(void *raw, int size, struct apfs_key *key)
 */
 int apfs_read_extentref_key(void *raw, int size, struct apfs_key *key)
 {
-	if (size != sizeof(struct apfs_phys_ext_key))
+	if (size != sizeof(struct apfs_phys_ext_key)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	key->id = apfs_cat_cnid((struct apfs_key_header *)raw);
 	key->type = apfs_cat_type((struct apfs_key_header *)raw);
 	key->number = 0;
@@ -223,21 +240,26 @@ int apfs_read_extentref_key(void *raw, int size, struct apfs_key *key)

 int apfs_read_snap_meta_key(void *raw, int size, struct apfs_key *key)
 {
-	if (size < sizeof(struct apfs_key_header))
+	if (size < sizeof(struct apfs_key_header)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	key->id = apfs_cat_cnid((struct apfs_key_header *)raw);
 	key->type = apfs_cat_type((struct apfs_key_header *)raw);
 	key->number = 0;

 	switch (key->type) {
 	case APFS_TYPE_SNAP_METADATA:
-		if (size != sizeof(struct apfs_snap_metadata_key))
+		if (size != sizeof(struct apfs_snap_metadata_key)) {
+			apfs_err(NULL, "bad key length (%d)", size);
 			return -EFSCORRUPTED;
+		}
 		key->name = NULL;
 		return 0;
 	case APFS_TYPE_SNAP_NAME:
 		if (size < sizeof(struct apfs_snap_name_key) + 1 || *((char *)raw + size - 1) != 0) {
 			/* snapshot name must have NULL-termination */
+			apfs_err(NULL, "invalid snap name key (%d)", size);
 			return -EFSCORRUPTED;
 		}
 		key->name = ((struct apfs_snap_name_key *)raw)->name;
@@ -251,8 +273,10 @@ int apfs_read_omap_snap_key(void *raw, int size, struct apfs_key *key)
 {
 	__le64 *xid = NULL;

-	if (size != sizeof(*xid))
+	if (size != sizeof(*xid)) {
+		apfs_err(NULL, "bad key length (%d)", size);
 		return -EFSCORRUPTED;
+	}
 	xid = raw;

 	key->id = le64_to_cpup(xid);
@@ -6,8 +6,9 @@
 #include <linux/fs.h>
 #include "apfs.h"

-void apfs_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
+void apfs_msg(struct super_block *sb, const char *prefix, const char *func, int line, const char *fmt, ...)
 {
+	char *sb_id = NULL;
 	struct va_format vaf;
 	va_list args;

@@ -16,7 +17,13 @@ void apfs_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
 	vaf.fmt = fmt;
 	vaf.va = &args;

-	printk("%sAPFS (%s): %pV\n", prefix, sb->s_id, &vaf);
+	/* The superblock is not available to all callers */
+	sb_id = sb ? sb->s_id : "?";
+
+	if (func)
+		printk("%sAPFS (%s): %pV (%s:%d)\n", prefix, sb_id, &vaf, func, line);
+	else
+		printk("%sAPFS (%s): %pV\n", prefix, sb_id, &vaf);

 	va_end(args);
 }
@@ -18,13 +18,17 @@ static struct dentry *apfs_lookup(struct inode *dir, struct dentry *dentry,
 		return ERR_PTR(-ENAMETOOLONG);

 	err = apfs_inode_by_name(dir, &dentry->d_name, &ino);
-	if (err && err != -ENODATA)
+	if (err && err != -ENODATA) {
+		apfs_err(dir->i_sb, "inode lookup by name failed");
 		return ERR_PTR(err);
+	}

 	if (!err) {
 		inode = apfs_iget(dir->i_sb, ino);
-		if (IS_ERR(inode))
+		if (IS_ERR(inode)) {
+			apfs_err(dir->i_sb, "iget failed");
 			return ERR_CAST(inode);
+		}
 	}

 	return d_splice_alias(inode, dentry);
@@ -33,9 +37,12 @@ static struct dentry *apfs_lookup(struct inode *dir, struct dentry *dentry,
 #if LINUX_VERSION_CODE < KERNEL_VERSION(5, 12, 0)
 static int apfs_symlink(struct inode *dir, struct dentry *dentry,
 			const char *symname)
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 static int apfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 			struct dentry *dentry, const char *symname)
+#else
+static int apfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
+			struct dentry *dentry, const char *symname)
 #endif
 {
 	/* Symlink permissions don't mean anything and their value is fixed */
@@ -78,8 +78,10 @@ static int apfs_cpm_lookup_oid(struct super_block *sb,
 	u32 map_count = le32_to_cpu(cpm->cpm_count);
 	int i;

-	if (map_count > apfs_max_maps_per_block(sb))
+	if (map_count > apfs_max_maps_per_block(sb)) {
+		apfs_err(sb, "block has too many maps (%d)", map_count);
 		return -EFSCORRUPTED;
+	}

 	for (i = 0; i < map_count; ++i) {
 		struct apfs_checkpoint_mapping *map = &cpm->cpm_map[i];
@@ -214,14 +216,17 @@ int apfs_remove_cpoint_map(struct super_block *sb, u64 bno)
 	int err = 0;

 	bh = apfs_read_cpm_block(sb);
-	if (!bh)
+	if (!bh) {
+		apfs_err(sb, "failed to read cpm block");
 		return -EIO;
+	}
 	cpm = (struct apfs_checkpoint_map_phys *)bh->b_data;
 	apfs_assert_in_transaction(sb, &cpm->cpm_o);

 	/* TODO: multiple cpm blocks? */
 	cpm_count = le32_to_cpu(cpm->cpm_count);
 	if (cpm_count > apfs_max_maps_per_block(sb)) {
+		apfs_err(sb, "block has too many maps (%d)", cpm_count);
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
@@ -240,6 +245,7 @@ int apfs_remove_cpoint_map(struct super_block *sb, u64 bno)
 			map->cpm_paddr = cpu_to_le64(apfs_data_index_to_bno(sb, curr_off - 1));
 	}
 	if (!bno_map) {
+		apfs_err(sb, "no mapping for bno 0x%llx", bno);
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
@@ -269,8 +275,10 @@ struct buffer_head *apfs_read_ephemeral_object(struct super_block *sb, u64 oid)
 	u32 desc_len = le32_to_cpu(raw_sb->nx_xp_desc_len);
 	u32 i;

-	if (!desc_blks || !desc_len)
+	if (!desc_blks || !desc_len) {
+		apfs_err(sb, "no blocks in checkpoint descriptor area");
 		return ERR_PTR(-EFSCORRUPTED);
+	}

 	/* Last block in the area is superblock; the rest are mapping blocks */
 	for (i = 0; i < desc_len - 1; ++i) {
@@ -281,8 +289,10 @@ struct buffer_head *apfs_read_ephemeral_object(struct super_block *sb, u64 oid)
 		int err;

 		bh = apfs_sb_bread(sb, cpm_bno);
-		if (!bh)
+		if (!bh) {
+			apfs_err(sb, "failed to read cpm block");
 			return ERR_PTR(-EIO);
+		}
 		cpm = (struct apfs_checkpoint_map_phys *)bh->b_data;

 		err = apfs_cpm_lookup_oid(sb, cpm, oid, &obj_bno);
@@ -290,15 +300,20 @@ struct buffer_head *apfs_read_ephemeral_object(struct super_block *sb, u64 oid)
 		cpm = NULL;
 		if (err == -EAGAIN) /* Search the next mapping block */
 			continue;
-		if (err)
+		if (err) {
+			apfs_err(sb, "cpm lookup failed for oid 0x%llx", oid);
 			return ERR_PTR(err);
+		}

 		bh = apfs_sb_bread(sb, obj_bno);
-		if (!bh)
+		if (!bh) {
+			apfs_err(sb, "failed to read ephemeral block");
 			return ERR_PTR(-EIO);
+		}
 		return bh;
 	}
-	return ERR_PTR(-EFSCORRUPTED); /* The mapping is missing */
+	apfs_err(sb, "no mapping for oid 0x%llx", oid);
+	return ERR_PTR(-EFSCORRUPTED);
 }

 /**
@@ -325,13 +340,16 @@ struct buffer_head *apfs_read_object_block(struct super_block *sb, u64 bno, bool
 	ASSERT(write || !preserve);

 	bh = apfs_sb_bread(sb, bno);
-	if (!bh)
+	if (!bh) {
+		apfs_err(sb, "failed to read object block 0x%llx", bno);
 		return ERR_PTR(-EIO);
+	}

 	obj = (struct apfs_obj_phys *)bh->b_data;
 	type = le32_to_cpu(obj->o_type);
 	ASSERT(!(type & APFS_OBJ_EPHEMERAL));
 	if (nxi->nx_flags & APFS_CHECK_NODES && !apfs_obj_verify_csum(sb, bh)) {
+		apfs_err(sb, "bad checksum for object in block 0x%llx", bno);
 		err = -EFSBADCRC;
 		goto fail;
 	}
@@ -345,10 +363,13 @@ struct buffer_head *apfs_read_object_block(struct super_block *sb, u64 bno, bool
 		return bh;

 	err = apfs_spaceman_allocate_block(sb, &new_bno, true /* backwards */);
-	if (err)
+	if (err) {
+		apfs_err(sb, "block allocation failed");
 		goto fail;
+	}
 	new_bh = apfs_getblk(sb, new_bno);
 	if (!new_bh) {
+		apfs_err(sb, "failed to map block for CoW (0x%llx)", new_bno);
 		err = -EIO;
 		goto fail;
 	}
@@ -361,6 +382,8 @@ struct buffer_head *apfs_read_object_block(struct super_block *sb, u64 bno, bool
 	 */
 	if (!preserve) {
 		err = apfs_free_queue_insert(sb, bh->b_blocknr, 1);
+		if (err)
+			apfs_err(sb, "free queue insertion failed for 0x%llx", (unsigned long long)bh->b_blocknr);
 	} else if ((type & APFS_OBJECT_TYPE_MASK) != APFS_OBJECT_TYPE_FS) {
 		vsb_raw = APFS_SB(sb)->s_vsb_raw;
 		apfs_assert_in_transaction(sb, &vsb_raw->apfs_o);
@@ -24,11 +24,14 @@ static int apfs_create_superblock_snapshot(struct super_block *sb, u64 *bno)
 	int err;

 	err = apfs_spaceman_allocate_block(sb, bno, true /* backwards */);
-	if (err)
+	if (err) {
+		apfs_err(sb, "block allocation failed");
 		goto fail;
+	}

 	snap_bh = apfs_getblk(sb, *bno);
 	if (!snap_bh) {
+		apfs_err(sb, "failed to map block for volume snap (0x%llx)", *bno);
 		err = -EIO;
 		goto fail;
 	}
@@ -88,11 +91,14 @@ static int apfs_create_snap_metadata_rec(struct inode *mntpoint, struct apfs_nod

 	err = apfs_btree_query(sb, &query);
 	if (err == 0) {
+		apfs_err(sb, "record exists for xid 0x%llx", xid);
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
-	if (err != -ENODATA)
+	if (err != -ENODATA) {
+		apfs_err(sb, "query failed for xid 0x%llx", xid);
 		goto fail;
+	}

 	apfs_key_set_hdr(APFS_TYPE_SNAP_METADATA, xid, &raw_key);

@@ -110,13 +116,15 @@ static int apfs_create_snap_metadata_rec(struct inode *mntpoint, struct apfs_nod
 	raw_val->extentref_tree_type = vsb_raw->apfs_extentref_tree_type;
 	raw_val->flags = 0;
 	raw_val->name_len = cpu_to_le16(name_len + 1); /* Count the null byte */
-	strcpy(raw_val->name, name);
+	strscpy(raw_val->name, name, name_len + 1);

 	apfs_assert_in_transaction(sb, &vsb_raw->apfs_o);
 	raw_val->inum = vsb_raw->apfs_next_obj_id;
 	le64_add_cpu(&vsb_raw->apfs_next_obj_id, 1);

 	err = apfs_btree_insert(query, &raw_key, sizeof(raw_key), raw_val, val_len);
+	if (err)
+		apfs_err(sb, "insertion failed for xid 0x%llx", xid);
 fail:
 	kfree(raw_val);
 	raw_val = NULL;
@@ -152,8 +160,10 @@ static int apfs_create_snap_name_rec(struct apfs_node *snap_root, const char *na
 		err = -EEXIST;
 		goto fail;
 	}
-	if (err != -ENODATA)
+	if (err != -ENODATA) {
+		apfs_err(sb, "query failed (%s)", name);
 		goto fail;
+	}

 	key_len = sizeof(*raw_key) + name_len + 1;
 	raw_key = kzalloc(key_len, GFP_KERNEL);
@@ -163,11 +173,13 @@ static int apfs_create_snap_name_rec(struct apfs_node *snap_root, const char *na
 	}
 	apfs_key_set_hdr(APFS_TYPE_SNAP_NAME, APFS_SNAP_NAME_OBJ_ID, raw_key);
 	raw_key->name_len = cpu_to_le16(name_len + 1); /* Count the null byte */
-	strcpy(raw_key->name, name);
+	strscpy(raw_key->name, name, name_len + 1);

 	raw_val.snap_xid = cpu_to_le64(APFS_NXI(sb)->nx_xid);

 	err = apfs_btree_insert(query, raw_key, key_len, &raw_val, sizeof(raw_val));
+	if (err)
+		apfs_err(sb, "insertion failed (%s)", name);
 fail:
 	kfree(raw_key);
 	raw_key = NULL;
@@ -176,30 +188,29 @@ fail:
 	return err;
 }

-static int apfs_create_snap_meta_records(struct inode *mntpoint, const char *name, u64 sblock_oid)
+static int apfs_create_snap_meta_records(struct inode *mntpoint, const char *name, int name_len, u64 sblock_oid)
 {
 	struct super_block *sb = mntpoint->i_sb;
 	struct apfs_superblock *vsb_raw = APFS_SB(sb)->s_vsb_raw;
 	struct apfs_node *snap_root = NULL;
-	size_t name_len;
 	int err;

 	snap_root = apfs_read_node(sb, le64_to_cpu(vsb_raw->apfs_snap_meta_tree_oid), APFS_OBJ_PHYSICAL, true /* write */);
-	if (IS_ERR(snap_root))
+	if (IS_ERR(snap_root)) {
+		apfs_err(sb, "failed to read snap meta root 0x%llx", le64_to_cpu(vsb_raw->apfs_snap_meta_tree_oid));
 		return PTR_ERR(snap_root);
+	}
 	apfs_assert_in_transaction(sb, &vsb_raw->apfs_o);
 	vsb_raw->apfs_snap_meta_tree_oid = cpu_to_le64(snap_root->object.oid);

-	name_len = strlen(name);
-	if (name_len > APFS_SNAP_MAX_NAMELEN) {
-		err = -EFSCORRUPTED;
+	err = apfs_create_snap_metadata_rec(mntpoint, snap_root, name, name_len, sblock_oid);
+	if (err) {
+		apfs_err(sb, "meta rec creation failed");
 		goto fail;
 	}
-
-	err = apfs_create_snap_metadata_rec(mntpoint, snap_root, name, name_len, sblock_oid);
-	if (err)
-		goto fail;
 	err = apfs_create_snap_name_rec(snap_root, name, name_len);
+	if (err)
+		apfs_err(sb, "name rec creation failed");

 fail:
 	apfs_node_free(snap_root);
@@ -213,8 +224,10 @@ static int apfs_create_new_extentref_tree(struct super_block *sb)
 	int err;

 	err = apfs_make_empty_btree_root(sb, APFS_OBJECT_TYPE_BLOCKREFTREE, &oid);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to make empty root");
 		return err;
+	}

 	apfs_assert_in_transaction(sb, &vsb_raw->apfs_o);
 	vsb_raw->apfs_extentref_tree_oid = cpu_to_le64(oid);
@@ -242,13 +255,17 @@ static int apfs_update_omap_snap_tree(struct super_block *sb, __le64 *oid_p)
 	/* An empty snapshots tree may not even have a root yet */
 	if (!oid) {
 		err = apfs_make_empty_btree_root(sb, APFS_OBJECT_TYPE_OMAP_SNAPSHOT, &oid);
-		if (err)
+		if (err) {
+			apfs_err(sb, "failed to make empty root");
 			return err;
+		}
 	}

 	root = apfs_read_node(sb, oid, APFS_OBJ_PHYSICAL, true /* write */);
-	if (IS_ERR(root))
+	if (IS_ERR(root)) {
+		apfs_err(sb, "failed to read omap snap root 0x%llx", oid);
 		return PTR_ERR(root);
+	}
 	oid = 0;

 	apfs_init_omap_snap_key(nxi->nx_xid, &key);
@@ -263,14 +280,19 @@ static int apfs_update_omap_snap_tree(struct super_block *sb, __le64 *oid_p)

 	err = apfs_btree_query(sb, &query);
 	if (err == 0) {
+		apfs_err(sb, "record exists for xid 0x%llx", nxi->nx_xid);
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
-	if (err != -ENODATA)
+	if (err != -ENODATA) {
+		apfs_err(sb, "query failed for xid 0x%llx", nxi->nx_xid);
 		goto fail;
+	}

 	raw_key = cpu_to_le64(nxi->nx_xid);
 	err = apfs_btree_insert(query, &raw_key, sizeof(raw_key), &raw_val, sizeof(raw_val));
+	if (err)
+		apfs_err(sb, "insertion failed for xid 0x%llx", nxi->nx_xid);
 	*oid_p = cpu_to_le64(root->object.block_nr);

 fail:
@@ -300,14 +322,18 @@ static int apfs_update_omap_snapshots(struct super_block *sb)

 	omap_blk = le64_to_cpu(vsb_raw->apfs_omap_oid);
 	bh = apfs_read_object_block(sb, omap_blk, true /* write */, false /* preserve */);
-	if (IS_ERR(bh))
+	if (IS_ERR(bh)) {
+		apfs_err(sb, "CoW failed for bno 0x%llx", omap_blk);
 		return PTR_ERR(bh);
+	}
 	omap = (struct apfs_omap_phys *)bh->b_data;

 	apfs_assert_in_transaction(sb, &omap->om_o);
 	le32_add_cpu(&omap->om_snap_count, 1);
 	omap->om_most_recent_snap = cpu_to_le64(xid);
 	err = apfs_update_omap_snap_tree(sb, &omap->om_snapshot_tree_oid);
+	if (err)
+		apfs_err(sb, "omap snap tree update failed");

 	omap = NULL;
 	brelse(bh);
@@ -322,7 +348,7 @@ static int apfs_update_omap_snapshots(struct super_block *sb)
 *
 * Returns 0 on success, or a negative error code in case of failure.
 */
-static int apfs_do_ioc_take_snapshot(struct inode *mntpoint, const char *name)
+static int apfs_do_ioc_take_snapshot(struct inode *mntpoint, const char *name, int name_len)
 {
 	struct super_block *sb = mntpoint->i_sb;
 	struct apfs_sb_info *sbi = APFS_SB(sb);
@@ -343,24 +369,34 @@ static int apfs_do_ioc_take_snapshot(struct inode *mntpoint, const char *name)
 	 * changes to the layout after the snapshot is set up.
 	 */
 	err = apfs_transaction_flush_all_inodes(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to flush all inodes");
 		goto fail;
+	}

 	err = apfs_create_superblock_snapshot(sb, &sblock_oid);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to snapshot superblock");
 		goto fail;
+	}

-	err = apfs_create_snap_meta_records(mntpoint, name, sblock_oid);
-	if (err)
+	err = apfs_create_snap_meta_records(mntpoint, name, name_len, sblock_oid);
+	if (err) {
+		apfs_err(sb, "failed to create snap meta records");
 		goto fail;
+	}

 	err = apfs_create_new_extentref_tree(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to create new extref tree");
 		goto fail;
+	}

 	err = apfs_update_omap_snapshots(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to update omap snapshots");
 		goto fail;
+	}

 	/*
 	 * The official reference allows old implementations to ignore extended
@@ -397,6 +433,7 @@ int apfs_ioc_take_snapshot(struct file *file, void __user *user_arg)
 	struct inode *inode = file_inode(file);
 	struct super_block *sb = inode->i_sb;
 	struct apfs_ioctl_snap_name *arg = NULL;
+	size_t name_len;
 	int err;

 	if (apfs_ino(inode) != APFS_ROOT_DIR_INO_NUM) {
@@ -406,8 +443,10 @@ int apfs_ioc_take_snapshot(struct file *file, void __user *user_arg)

 #if LINUX_VERSION_CODE < KERNEL_VERSION(5, 12, 0)
 	if (!inode_owner_or_capable(inode))
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 	if (!inode_owner_or_capable(&init_user_ns, inode))
+#else
+	if (!inode_owner_or_capable(&nop_mnt_idmap, inode))
 #endif
 		return -EPERM;

@@ -426,7 +465,14 @@ int apfs_ioc_take_snapshot(struct file *file, void __user *user_arg)
 		goto fail;
 	}

-	err = apfs_do_ioc_take_snapshot(inode, arg->name);
+	name_len = strnlen(arg->name, sizeof(arg->name));
+	if (name_len == sizeof(arg->name)) {
+		apfs_warn(sb, "snapshot name is too long (%d)", (int)name_len);
+		err = -EINVAL;
+		goto fail;
+	}
+
+	err = apfs_do_ioc_take_snapshot(inode, arg->name, name_len);
 fail:
 	kfree(arg);
 	arg = NULL;
@@ -439,8 +485,10 @@ static int apfs_snap_xid_from_query(struct apfs_query *query, u64 *xid)
 	char *raw = query->node->object.data;
 	__le64 *val = NULL;

-	if (query->len != sizeof(*val))
+	if (query->len != sizeof(*val)) {
+		apfs_err(query->node->object.sb, "bad value length (%d)", query->len);
 		return -EFSCORRUPTED;
+	}
 	val = (__le64 *)(raw + query->off);

 	*xid = le64_to_cpup(val);
@@ -463,10 +511,15 @@ static int apfs_snapshot_name_to_xid(struct apfs_node *snap_root, const char *na
 	query->flags |= APFS_QUERY_SNAP_META | APFS_QUERY_EXACT;

 	err = apfs_btree_query(sb, &query);
-	if (err)
+	if (err) {
+		if (err != -ENODATA)
+			apfs_err(sb, "query failed (%s)", name);
 		goto fail;
+	}

 	err = apfs_snap_xid_from_query(query, xid);
+	if (err)
+		apfs_err(sb, "bad snap name record (%s)", name);
 fail:
 	apfs_free_query(query);
 	query = NULL;
@@ -478,8 +531,10 @@ static int apfs_snap_sblock_from_query(struct apfs_query *query, u64 *sblock_oid
 	char *raw = query->node->object.data;
 	struct apfs_snap_metadata_val *val = NULL;

-	if (query->len < sizeof(*val))
+	if (query->len < sizeof(*val)) {
+		apfs_err(query->node->object.sb, "bad value length (%d)", query->len);
 		return -EFSCORRUPTED;
+	}
 	val = (struct apfs_snap_metadata_val *)(raw + query->off);

 	*sblock_oid = le64_to_cpu(val->sblock_oid);
@@ -502,10 +557,14 @@ static int apfs_snapshot_xid_to_sblock(struct apfs_node *snap_root, u64 xid, u64
 	query->flags |= APFS_QUERY_SNAP_META | APFS_QUERY_EXACT;

 	err = apfs_btree_query(sb, &query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "query failed for xid 0x%llx", xid);
 		goto fail;
+	}

 	err = apfs_snap_sblock_from_query(query, sblock_oid);
+	if (err)
+		apfs_err(sb, "bad snap meta record for xid 0x%llx", xid);
 fail:
 	apfs_free_query(query);
 	query = NULL;
@@ -533,17 +592,24 @@ int apfs_switch_to_snapshot(struct super_block *sb)
 	ASSERT(sb->s_flags & SB_RDONLY);

 	name = sbi->s_snap_name;
-	if (strlen(name) > APFS_SNAP_MAX_NAMELEN)
+	if (strlen(name) > APFS_SNAP_MAX_NAMELEN) {
+		apfs_warn(sb, "snapshot name is too long");
 		return -EINVAL;
+	}

 	snap_root = apfs_read_node(sb, le64_to_cpu(vsb_raw->apfs_snap_meta_tree_oid), APFS_OBJ_PHYSICAL, false /* write */);
-	if (IS_ERR(snap_root))
+	if (IS_ERR(snap_root)) {
+		apfs_err(sb, "failed to read snap meta root 0x%llx", le64_to_cpu(vsb_raw->apfs_snap_meta_tree_oid));
 		return PTR_ERR(snap_root);
+	}
 	vsb_raw = NULL;

 	err = apfs_snapshot_name_to_xid(snap_root, name, &xid);
-	if (err)
+	if (err) {
+		if (err == -ENODATA)
+			apfs_info(sb, "no snapshot under that name (%s)", name);
 		goto fail;
+	}
 	sbi->s_snap_xid = xid;

 	err = apfs_snapshot_xid_to_sblock(snap_root, xid, &sblock_oid);
@@ -552,6 +618,8 @@ int apfs_switch_to_snapshot(struct super_block *sb)

 	apfs_unmap_volume_super(sb);
 	err = apfs_map_volume_super_bno(sb, sblock_oid, nxi->nx_flags & APFS_CHECK_NODES);
+	if (err)
+		apfs_err(sb, "failed to map volume block 0x%llx", sblock_oid);

 fail:
 	apfs_node_free(snap_root);
@@ -87,8 +87,10 @@ static int apfs_read_spaceman_dev(struct super_block *sb,

 	/* Check that all the cib addresses fit in the spaceman block */
 	if ((long long)spaceman->sm_addr_offset +
-	    (long long)spaceman->sm_cib_count * sizeof(u64) > sb->s_blocksize)
+	    (long long)spaceman->sm_cib_count * sizeof(u64) > sb->s_blocksize) {
+		apfs_err(sb, "too many cibs (%u)", spaceman->sm_cib_count);
 		return -EFSCORRUPTED;
+	}

 	return 0;
 }
@@ -146,10 +148,14 @@ static int apfs_update_ip_bm_free_next(struct super_block *sb)
 	__le16 *free_next;
 	int i;

-	if (free_next_off > sb->s_blocksize)
+	if (free_next_off > sb->s_blocksize) {
+		apfs_err(sb, "offset out of bounds (%u)", free_next_off);
 		return -EFSCORRUPTED;
-	if (free_next_off + bmap_count * sizeof(*free_next) > sb->s_blocksize)
+	}
+	if (free_next_off + bmap_count * sizeof(*free_next) > sb->s_blocksize) {
+		apfs_err(sb, "free next out of bounds (%u-%u)", free_next_off, bmap_count * (u32)sizeof(*free_next));
 		return -EFSCORRUPTED;
+	}
 	free_next = (void *)raw + free_next_off;

 	for (i = 0; i < bmap_count; ++i) {
@@ -187,19 +193,25 @@ static int apfs_rotate_ip_bitmaps(struct super_block *sb)
 	}

 	xid = apfs_spaceman_get_64(sb, le32_to_cpu(sm_raw->sm_ip_bm_xid_offset));
-	if (!xid)
+	if (!xid) {
+		apfs_err(sb, "xid out of bounds (%u)", le32_to_cpu(sm_raw->sm_ip_bm_xid_offset));
 		return -EFSCORRUPTED;
+	}
 	*xid = cpu_to_le64(nxi->nx_xid);

 	free_head = le16_to_cpu(sm_raw->sm_ip_bm_free_head);
 	free_tail = le16_to_cpu(sm_raw->sm_ip_bm_free_tail);

 	curr_bmap_off = apfs_spaceman_get_64(sb, le32_to_cpu(sm_raw->sm_ip_bitmap_offset));
-	if (!curr_bmap_off)
+	if (!curr_bmap_off) {
+		apfs_err(sb, "bmap offset out of bounds (%u)", le32_to_cpu(sm_raw->sm_ip_bitmap_offset));
 		return -EFSCORRUPTED;
+	}
 	old_bh = apfs_sb_bread(sb, bmap_base + le64_to_cpup(curr_bmap_off));
-	if (!old_bh)
+	if (!old_bh) {
+		apfs_err(sb, "failed to read current ip bitmap (0x%llx)", bmap_base + le64_to_cpup(curr_bmap_off));
 		return -EIO;
+	}

 	*curr_bmap_off = cpu_to_le64(free_head);
 	free_head = (free_head + 1) % bmap_length;
@@ -207,11 +219,14 @@ static int apfs_rotate_ip_bitmaps(struct super_block *sb)
 	sm_raw->sm_ip_bm_free_head = cpu_to_le16(free_head);
 	sm_raw->sm_ip_bm_free_tail = cpu_to_le16(free_tail);
 	err = apfs_update_ip_bm_free_next(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to update bitmap ring");
 		goto out;
+	}

 	new_bh = apfs_getblk(sb, bmap_base + le64_to_cpup(curr_bmap_off));
 	if (!new_bh) {
+		apfs_err(sb, "failed to map block for CoW (0x%llx)", bmap_base + le64_to_cpup(curr_bmap_off));
 		err = -EIO;
 		goto out;
 	}
@@ -251,8 +266,10 @@ static int apfs_fq_rec_from_query(struct apfs_query *query, struct apfs_fq_rec *
 	char *raw = query->node->object.data;
 	struct apfs_spaceman_free_queue_key *key;

-	if (query->key_len != sizeof(*key))
+	if (query->key_len != sizeof(*key)) {
+		apfs_err(query->node->object.sb, "bad key length (%d)", query->key_len);
 		return -EFSCORRUPTED;
+	}
 	key = (struct apfs_spaceman_free_queue_key *)(raw + query->key_off);

 	fqrec->xid = le64_to_cpu(key->sfqk_xid);
@@ -265,6 +282,7 @@ static int apfs_fq_rec_from_query(struct apfs_query *query, struct apfs_fq_rec *
 		fqrec->len = le64_to_cpup((__le64 *)(raw + query->off));
 		return 0;
 	}
+	apfs_err(query->node->object.sb, "bad value length (%d)", query->len);
 	return -EFSCORRUPTED;
 }

@@ -331,23 +349,32 @@ static int apfs_flush_fq_rec(struct apfs_node *root, u64 xid, u64 *len)
 	query->flags |= APFS_QUERY_FREE_QUEUE | APFS_QUERY_ANY_NUMBER | APFS_QUERY_EXACT;

 	err = apfs_btree_query(sb, &query);
-	if (err)
+	if (err) {
+		if (err != -ENODATA)
+			apfs_err(sb, "query failed for xid 0x%llx, paddr 0x%llx", xid, 0ULL);
 		goto fail;
+	}
 	err = apfs_fq_rec_from_query(query, &fqrec);
-	if (err)
+	if (err) {
+		apfs_err(sb, "bad free queue rec for xid 0x%llx", xid);
 		goto fail;
+	}

 	for (bno = fqrec.bno; bno < fqrec.bno + fqrec.len; ++bno) {
 		if(apfs_block_in_ip(sm, bno))
 			err = apfs_ip_mark_free(sb, bno);
 		else
 			err = apfs_main_free(sb, bno);
-		if(err)
+		if (err) {
 			apfs_err(sb, "freeing block 0x%llx failed (%d)", (unsigned long long)bno, err);
+			goto fail;
+		}
 	}
 	err = apfs_btree_remove(query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "removal failed for xid 0x%llx", xid);
 		goto fail;
+	}
 	*len = fqrec.len;

 fail:
@@ -391,8 +418,10 @@ static int apfs_flush_free_queue(struct super_block *sb, unsigned qid)

 	fq_root = apfs_read_node(sb, le64_to_cpu(fq->sfq_tree_oid),
 				 APFS_OBJ_EPHEMERAL, true /* write */);
-	if (IS_ERR(fq_root))
+	if (IS_ERR(fq_root)) {
+		apfs_err(sb, "failed to read fq root 0x%llx", le64_to_cpu(fq->sfq_tree_oid));
 		return PTR_ERR(fq_root);
+	}

 	/* Preserve a few transactions */
 	while (oldest + 4 < nxi->nx_xid) {
@@ -407,6 +436,7 @@ static int apfs_flush_free_queue(struct super_block *sb, unsigned qid)
 				err = 0;
 				break;
 			} else if (err) {
+				apfs_err(sb, "failed to flush fq");
 				goto fail;
 			} else {
 				le64_add_cpu(&fq->sfq_count, -count);
@@ -461,8 +491,10 @@ int apfs_read_spaceman(struct super_block *sb)
 	spaceman->sm_free_cache_base = spaceman->sm_free_cache_blkcnt = 0;

 	sm_bh = apfs_read_ephemeral_object(sb, oid);
-	if (IS_ERR(sm_bh))
+	if (IS_ERR(sm_bh)) {
+		apfs_err(sb, "ephemeral read failed for oid 0x%llx", oid);
 		return PTR_ERR(sm_bh);
+	}
 	sm_raw = (struct apfs_spaceman_phys *)sm_bh->b_data;

 	sm_flags = le32_to_cpu(sm_raw->sm_flags);
@@ -472,13 +504,16 @@ int apfs_read_spaceman(struct super_block *sb)

 	/* Only read the main device; fusion drives are not yet supported */
 	err = apfs_read_spaceman_dev(sb, &sm_raw->sm_dev[APFS_SD_MAIN]);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to read main device");
 		goto fail;
+	}

 	spaceman->sm_blocks_per_chunk =
 				le32_to_cpu(sm_raw->sm_blocks_per_chunk);
 	spaceman->sm_chunks_per_cib = le32_to_cpu(sm_raw->sm_chunks_per_cib);
 	if (spaceman->sm_chunks_per_cib > apfs_max_chunks_per_cib(sb)) {
+		apfs_err(sb, "too many chunks per cib (%u)", spaceman->sm_chunks_per_cib);
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
@@ -486,14 +521,20 @@ int apfs_read_spaceman(struct super_block *sb)
 	spaceman->sm_bh = sm_bh;
 	spaceman->sm_raw = sm_raw;
 	err = apfs_rotate_ip_bitmaps(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to rotate ip bitmaps");
 		goto fail;
+	}
 	err = apfs_flush_free_queue(sb, APFS_SFQ_IP);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to flush ip fq");
 		goto fail;
+	}
 	err = apfs_flush_free_queue(sb, APFS_SFQ_MAIN);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to flush main fq");
 		goto fail;
+	}
 	return 0;

 fail:
@@ -625,11 +666,14 @@ int apfs_free_queue_insert_nocache(struct super_block *sb, u64 bno, u64 count)
 	struct apfs_spaceman *sm = APFS_SM(sb);
 	struct apfs_spaceman_phys *sm_raw = sm->sm_raw;
 	struct apfs_spaceman_free_queue *fq;
-	struct apfs_node *fq_root;
+	struct apfs_node *fq_root = NULL;
+	struct apfs_btree_info *fq_info = NULL;
 	struct apfs_query *query = NULL;
 	struct apfs_spaceman_free_queue_key raw_key;
 	__le64 raw_val;
 	struct apfs_key key;
+	u64 node_count;
+	u16 node_limit;
 	int err;

 	if (apfs_block_in_ip(sm, bno))
@@ -639,8 +683,10 @@ int apfs_free_queue_insert_nocache(struct super_block *sb, u64 bno, u64 count)

 	fq_root = apfs_read_node(sb, le64_to_cpu(fq->sfq_tree_oid),
 				 APFS_OBJ_EPHEMERAL, true /* write */);
-	if (IS_ERR(fq_root))
+	if (IS_ERR(fq_root)) {
+		apfs_err(sb, "failed to read fq root 0x%llx", le64_to_cpu(fq->sfq_tree_oid));
 		return PTR_ERR(fq_root);
+	}

 	query = apfs_alloc_query(fq_root, NULL /* parent */);
 	if (!query) {
@@ -653,8 +699,10 @@ int apfs_free_queue_insert_nocache(struct super_block *sb, u64 bno, u64 count)
 	query->flags |= APFS_QUERY_FREE_QUEUE;

 	err = apfs_btree_query(sb, &query);
-	if (err && err != -ENODATA)
+	if (err && err != -ENODATA) {
+		apfs_err(sb, "query failed for xid 0x%llx, paddr 0x%llx", nxi->nx_xid, bno);
 		goto fail;
+	}

 	raw_key.sfqk_xid = cpu_to_le64(nxi->nx_xid);
 	raw_key.sfqk_paddr = cpu_to_le64(bno);
@@ -665,8 +713,24 @@ int apfs_free_queue_insert_nocache(struct super_block *sb, u64 bno, u64 count)
 		raw_val = cpu_to_le64(count);
 		err = apfs_btree_insert(query, &raw_key, sizeof(raw_key), &raw_val, sizeof(raw_val));
 	}
-	if (err)
+	if (err) {
+		apfs_err(sb, "insertion failed for xid 0x%llx, paddr 0x%llx", nxi->nx_xid, bno);
 		goto fail;
+	}
+
+	fq_info = (void *)fq_root->object.data + sb->s_blocksize - sizeof(*fq_info);
+	node_count = le64_to_cpu(fq_info->bt_node_count);
+	node_limit = le16_to_cpu(fq->sfq_tree_node_limit);
+	if (node_count > node_limit) {
+		/*
+		 * Ideally this should never happen, but at this point I can't
+		 * be certain of that (TODO). If it does happen, it's best to
+		 * abort and avoid corruption.
+		 */
+		apfs_alert(sb, "free queue has too many nodes (%llu > %u)", node_count, node_limit);
+		err = -EFSCORRUPTED;
+		goto fail;
+	}

 	if (!fq->sfq_oldest_xid)
 		fq->sfq_oldest_xid = cpu_to_le64(nxi->nx_xid);
@@ -719,8 +783,10 @@ int apfs_free_queue_insert(struct super_block *sb, u64 bno, u64 count)

 	/* Failed to extend the cache, so flush it and replace it */
 	err = apfs_free_queue_insert_nocache(sb, sm->sm_free_cache_base, sm->sm_free_cache_blkcnt);
-	if (err)
+	if (err) {
+		apfs_err(sb, "fq cache flush failed (0x%llx-0x%llx)", sm->sm_free_cache_base, sm->sm_free_cache_blkcnt);
 		return err;
+	}
 	sm->sm_free_cache_base = bno;
 	sm->sm_free_cache_blkcnt = count;
 	return 0;
@@ -763,20 +829,25 @@ static int apfs_chunk_alloc_free(struct super_block *sb,
 	if (!ci->ci_bitmap_addr) {
 		u64 bmap_bno;

-		/* Freeing a block in an all-free chunk? */
-		if(!is_alloc)
+		if(!is_alloc) {
+			apfs_err(sb, "attempt to free block in all-free chunk");
 			return -EFSCORRUPTED;
+		}

 		/* All blocks in this chunk are free */
 		bmap_bno = apfs_ip_find_free(sb);
-		if (!bmap_bno)
+		if (!bmap_bno) {
+			apfs_err(sb, "no free blocks in ip");
 			return -EFSCORRUPTED;
+		}
 		bmap_bh = apfs_sb_bread(sb, bmap_bno);
 	} else {
 		bmap_bh = apfs_sb_bread(sb, le64_to_cpu(ci->ci_bitmap_addr));
 	}
-	if (!bmap_bh)
+	if (!bmap_bh) {
+		apfs_err(sb, "failed to read bitmap block");
 		return -EIO;
+	}
 	bmap = bmap_bh->b_data;
 	if (!ci->ci_bitmap_addr) {
 		memset(bmap, 0, sb->s_blocksize);
@@ -790,12 +861,14 @@ static int apfs_chunk_alloc_free(struct super_block *sb,

 		new_bmap_bno = apfs_ip_find_free(sb);
 		if (!new_bmap_bno) {
+			apfs_err(sb, "no free blocks in ip");
 			err = -EFSCORRUPTED;
 			goto fail;
 		}

 		new_bmap_bh = apfs_getblk(sb, new_bmap_bno);
 		if (!new_bmap_bh) {
+			apfs_err(sb, "failed to map new bmap block (0x%llx)", new_bmap_bno);
 			err = -EIO;
 			goto fail;
 		}
@@ -803,8 +876,10 @@ static int apfs_chunk_alloc_free(struct super_block *sb,
 		err = apfs_free_queue_insert(sb, bmap_bh->b_blocknr, 1);
 		brelse(bmap_bh);
 		bmap_bh = new_bmap_bh;
-		if (err)
+		if (err) {
+			apfs_err(sb, "free queue insertion failed");
 			goto fail;
+		}
 		bmap = bmap_bh->b_data;
 	}
 	apfs_ip_mark_used(sb, bmap_bh->b_blocknr);
@@ -816,12 +891,14 @@ static int apfs_chunk_alloc_free(struct super_block *sb,

 		new_cib_bno = apfs_ip_find_free(sb);
 		if (!new_cib_bno) {
+			apfs_err(sb, "no free blocks in ip");
 			err = -EFSCORRUPTED;
 			goto fail;
 		}

 		new_cib_bh = apfs_getblk(sb, new_cib_bno);
 		if (!new_cib_bh) {
+			apfs_err(sb, "failed to map new cib block (0x%llx)", new_cib_bno);
 			err = -EIO;
 			goto fail;
 		}
@@ -829,8 +906,10 @@ static int apfs_chunk_alloc_free(struct super_block *sb,
 		err = apfs_free_queue_insert(sb, (*cib_bh)->b_blocknr, 1);
 		brelse(*cib_bh);
 		*cib_bh = new_cib_bh;
-		if (err)
+		if (err) {
+			apfs_err(sb, "free queue insertion failed");
 			goto fail;
+		}

 		err = apfs_transaction_join(sb, *cib_bh);
 		if (err)
@@ -857,6 +936,7 @@ static int apfs_chunk_alloc_free(struct super_block *sb,
 	if(is_alloc) {
 		*bno = apfs_chunk_find_free(sb, bmap, le64_to_cpu(ci->ci_addr));
 		if (!*bno) {
+			apfs_err(sb, "no free blocks in chunk");
 			err = -EFSCORRUPTED;
 			goto fail;
 		}
@@ -864,6 +944,7 @@ static int apfs_chunk_alloc_free(struct super_block *sb,
 		sm->sm_free_count -= 1;
 	} else {
 		if(!apfs_chunk_mark_free(sb, bmap, *bno)) {
+			apfs_err(sb, "block already marked as free (0x%llx)", *bno);
 			le32_add_cpu(&ci->ci_free_count, -1);
 			set_buffer_csum(*cib_bh);
 			mark_buffer_dirty(*cib_bh);
@@ -924,8 +1005,10 @@ static int apfs_cib_allocate_block(struct super_block *sb,

 	/* Avoid out-of-bounds operations on corrupted cibs */
 	chunk_count = le32_to_cpu(cib->cib_chunk_info_count);
-	if (chunk_count > sm->sm_chunks_per_cib)
+	if (chunk_count > sm->sm_chunks_per_cib) {
+		apfs_err(sb, "too many chunks in cib (%u)", chunk_count);
 		return -EFSCORRUPTED;
+	}

 	for (i = 0; i < chunk_count; ++i) {
 		int index;
@@ -936,6 +1019,8 @@ static int apfs_cib_allocate_block(struct super_block *sb,
 		err = apfs_chunk_allocate_block(sb, cib_bh, index, bno);
 		if (err == -ENOSPC) /* This chunk is full */
 			continue;
+		if (err)
+			apfs_err(sb, "error during allocation");
 		return err;
 	}
 	return -ENOSPC;
@@ -966,8 +1051,10 @@ int apfs_spaceman_allocate_block(struct super_block *sb, u64 *bno, bool backward

 		cib_bno = apfs_spaceman_read_cib_addr(sb, index);
 		cib_bh = apfs_sb_bread(sb, cib_bno);
-		if (!cib_bh)
+		if (!cib_bh) {
+			apfs_err(sb, "failed to read cib");
 			return -EIO;
+		}

 		err = apfs_cib_allocate_block(sb, &cib_bh, bno, backwards);
 		if (!err) {
@@ -980,6 +1067,8 @@ int apfs_spaceman_allocate_block(struct super_block *sb, u64 *bno, bool backward
 		brelse(cib_bh);
 		if (err == -ENOSPC) /* This cib is full */
 			continue;
+		if (err)
+			apfs_err(sb, "error during allocation");
 		return err;
 	}
 	return -ENOSPC;
@@ -1013,8 +1102,10 @@ static int apfs_main_free(struct super_block *sb, u64 bno)
 	u64 cib_bno;
 	int err;

-	if(!sm_raw->sm_blocks_per_chunk || !sm_raw->sm_chunks_per_cib)
+	if(!sm_raw->sm_blocks_per_chunk || !sm_raw->sm_chunks_per_cib) {
+		apfs_err(sb, "block or chunk count not set");
 		return -EINVAL;
+	}
 	/* TODO: use bitshifts instead of do_div() */
 	chunk_idx = bno;
 	do_div(chunk_idx, sm->sm_blocks_per_chunk);
@@ -1023,8 +1114,10 @@ static int apfs_main_free(struct super_block *sb, u64 bno)

 	cib_bno = apfs_spaceman_read_cib_addr(sb, cib_idx);
 	cib_bh = apfs_sb_bread(sb, cib_bno);
-	if (!cib_bh)
+	if (!cib_bh) {
+		apfs_err(sb, "failed to read cib");
 		return -EIO;
+	}

 	err = apfs_chunk_free(sb, &cib_bh, chunk_idx, bno);
 	if (!err) {
@@ -1035,6 +1128,8 @@ static int apfs_main_free(struct super_block *sb, u64 bno)
 		set_buffer_csum(sm->sm_bh);
 	}
 	brelse(cib_bh);
+	if (err)
+		apfs_err(sb, "error during free");

 	return err;
 }
@@ -272,11 +272,13 @@ static void apfs_update_software_info(struct super_block *sb)
 	memmove(mod_by + 1, mod_by, (APFS_MAX_HIST - 1) * sizeof(*mod_by));

 	memset(mod_by->id, 0, sizeof(mod_by->id));
-	strcpy(mod_by->id, APFS_MODULE_ID_STRING);
+	strscpy(mod_by->id, APFS_MODULE_ID_STRING, sizeof(mod_by->id));
 	mod_by->timestamp = cpu_to_le64(ktime_get_real_ns());
 	mod_by->last_xid = cpu_to_le64(APFS_NXI(sb)->nx_xid);
 }

+static struct file_system_type apfs_fs_type;
+
 /**
 * apfs_unmap_main_super - Clean up apfs_map_main_super()
 * @sbi:	in-memory superblock info
@@ -286,11 +288,15 @@ static void apfs_update_software_info(struct super_block *sb)
 static inline void apfs_unmap_main_super(struct apfs_sb_info *sbi)
 {
 	struct apfs_nxsb_info *nxi = sbi->s_nxi;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(6, 5, 0)
 	fmode_t mode = FMODE_READ | FMODE_EXCL;
+#endif
 	struct apfs_object *obj = NULL;

+#if LINUX_VERSION_CODE < KERNEL_VERSION(6, 5, 0)
 	if (nxi->nx_flags & APFS_READWRITE)
 		mode |= FMODE_WRITE;
+#endif

 	lockdep_assert_held(&nxs_mutex);

@@ -304,7 +310,12 @@ static inline void apfs_unmap_main_super(struct apfs_sb_info *sbi)
 	obj->o_bh = NULL;
 	obj = NULL;

+#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 5, 0)
+	blkdev_put(nxi->nx_bdev, &apfs_fs_type);
+#else
 	blkdev_put(nxi->nx_bdev, mode);
+#endif
+
 	list_del(&nxi->nx_list);
 	kfree(nxi);
 out:
@@ -1450,8 +1461,6 @@ static int apfs_set_super(struct super_block *sb, void *data)
 	return err;
 }

-static struct file_system_type apfs_fs_type;
-
 /*
 * Wrapper for lookup_bdev() that supports older kernels.
 */
@@ -1480,7 +1489,11 @@ static int apfs_lookup_bdev(const char *pathname, dev_t *dev)
 *
 * Returns 0 on success, or a negative error code in case of failure.
 */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 5, 0)
+static int apfs_attach_nxi(struct apfs_sb_info *sbi, const char *dev_name, blk_mode_t mode)
+#else
 static int apfs_attach_nxi(struct apfs_sb_info *sbi, const char *dev_name, fmode_t mode)
+#endif
 {
 	struct apfs_nxsb_info *nxi;
 	dev_t dev = 0;
@@ -1500,7 +1513,11 @@ static int apfs_attach_nxi(struct apfs_sb_info *sbi, const char *dev_name, fmode
 		if (!nxi)
 			return -ENOMEM;

+#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 5, 0)
+		bdev = blkdev_get_by_path(dev_name, mode, &apfs_fs_type, NULL);
+#else
 		bdev = blkdev_get_by_path(dev_name, mode, &apfs_fs_type);
+#endif
 		if (IS_ERR(bdev)) {
 			kfree(nxi);
 			return PTR_ERR(bdev);
@@ -1527,7 +1544,11 @@ static struct dentry *apfs_mount(struct file_system_type *fs_type, int flags,
 	struct apfs_nxsb_info *nxi;
 	struct super_block *sb;
 	struct apfs_sb_info *sbi;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 5, 0)
+	blk_mode_t mode = sb_open_mode(flags);
+#else
 	fmode_t mode = FMODE_READ | FMODE_EXCL;
+#endif
 	int error = 0;

 	mutex_lock(&nxs_mutex);
@@ -1544,8 +1565,10 @@ static struct dentry *apfs_mount(struct file_system_type *fs_type, int flags,
 	if (sbi->s_snap_name)
 		flags |= SB_RDONLY;

+#if LINUX_VERSION_CODE < KERNEL_VERSION(6, 5, 0)
 	if (!(flags & SB_RDONLY))
 		mode |= FMODE_WRITE;
+#endif

 	error = apfs_attach_nxi(sbi, dev_name, mode);
 	if (error)
@@ -1572,7 +1595,9 @@ static struct dentry *apfs_mount(struct file_system_type *fs_type, int flags,
 		error = apfs_map_main_super(sb);
 		if (error)
 			goto out_deactivate_super;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(6, 5, 0)
 		sb->s_mode = mode;
+#endif
 		snprintf(sb->s_id, sizeof(sb->s_id), "%xg", sb->s_dev);
 		error = apfs_fill_super(sb, data, flags & SB_SILENT ? 1 : 0);
 		if (error)
@@ -35,6 +35,7 @@ static const char *apfs_get_link(struct dentry *dentry, struct inode *inode,
 	size = __apfs_xattr_get(inode, APFS_XATTR_NAME_SYMLINK,
 				NULL /* buffer */, 0 /* size */);
 	if (size < 0) { /* TODO: return a better error code */
+		apfs_err(sb, "symlink size read failed");
 		err = size;
 		goto fail;
 	}
@@ -47,13 +48,13 @@ static const char *apfs_get_link(struct dentry *dentry, struct inode *inode,

 	size = __apfs_xattr_get(inode, APFS_XATTR_NAME_SYMLINK, target, size);
 	if (size < 0) {
+		apfs_err(sb, "symlink read failed");
 		err = size;
 		goto fail;
 	}
 	if (size == 0 || *(target + size - 1) != 0) {
 		/* Target path must be NULL-terminated */
-		apfs_alert(sb, "bad link target in inode 0x%llx",
-			   apfs_ino(inode));
+		apfs_err(sb, "bad link target in inode 0x%llx", apfs_ino(inode));
 		err = -EFSCORRUPTED;
 		goto fail;
 	}
@@ -95,13 +95,17 @@ static int apfs_cpoint_init_desc(struct super_block *sb)
 	u32 new_sb_index;
 	int err;

-	if (!desc_blks || !desc_len)
+	if (!desc_blks || !desc_len) {
+		apfs_err(sb, "bad checkpoint descriptor area");
 		return -EFSCORRUPTED;
+	}

 	err = apfs_cpoint_init_area(sb, desc_base, desc_blks,
 				    desc_next, desc_len);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to init area");
 		return err;
+	}

 	/* Now update the superblock with the new checkpoint */

@@ -149,13 +153,17 @@ static int apfs_cpoint_init_data(struct super_block *sb)
 	u32 data_len = le32_to_cpu(raw_sb->nx_xp_data_len);
 	int err;

-	if (!data_blks || !data_len)
+	if (!data_blks || !data_len) {
+		apfs_err(sb, "bad checkpoint data area");
 		return -EFSCORRUPTED;
+	}

 	err = apfs_cpoint_init_area(sb, data_base, data_blks,
 				    data_next, data_len);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to init area");
 		return err;
+	}

 	/* Apparently the previous checkpoint gets invalidated right away */
 	apfs_assert_in_transaction(sb, &raw_sb->nx_o);
@@ -219,14 +227,17 @@ static int apfs_update_mapping_blocks(struct super_block *sb)
 		int j;

 		bh = apfs_sb_bread(sb, desc_base + desc_curr);
-		if (!bh)
+		if (!bh) {
+			apfs_err(sb, "failed to read cpm block");
 			return -EINVAL;
+		}
 		ASSERT(buffer_trans(bh));
 		cpm = (struct apfs_checkpoint_map_phys *)bh->b_data;
 		apfs_assert_in_transaction(sb, &cpm->cpm_o);

 		map_count = le32_to_cpu(cpm->cpm_count);
 		if (map_count > apfs_max_maps_per_block(sb)) {
+			apfs_err(sb, "block has too many maps (%d)", map_count);
 			brelse(bh);
 			return -EFSCORRUPTED;
 		}
@@ -290,6 +301,7 @@ int apfs_cpoint_data_free(struct super_block *sb, u64 bno)
 		new_bh = apfs_getblk(sb, apfs_data_index_to_bno(sb, i));
 		old_bh = apfs_sb_bread(sb, apfs_data_index_to_bno(sb, i + 1));
 		if (!new_bh || !old_bh) {
+			apfs_err(sb, "failed to map blocks in data area");
 			brelse(new_bh);
 			brelse(old_bh);
 			return -EIO;
@@ -327,12 +339,18 @@ static int apfs_checkpoint_start(struct super_block *sb)
 	ASSERT(!(sb->s_flags & SB_RDONLY));

 	err = apfs_cpoint_init_desc(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to init descriptor area");
 		return err;
+	}
 	err = apfs_cpoint_init_data(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to init data area");
 		return err;
+	}
 	err = apfs_update_mapping_blocks(sb);
+	if (err)
+		apfs_err(sb, "failed to update checkpoint mappings");

 	return err;
 }
@@ -444,12 +462,16 @@ int apfs_transaction_start(struct super_block *sb, struct apfs_max_ops maxops)
 		nx_trans->t_starts_count = 0;

 		err = apfs_checkpoint_start(sb);
-		if (err)
+		if (err) {
+			apfs_err(sb, "failed to start a new checkpoint");
 			goto fail;
+		}

 		err = apfs_read_spaceman(sb);
-		if (err)
+		if (err) {
+			apfs_err(sb, "failed to read the spaceman");
 			goto fail;
+		}
 	}

 	/* Don't start transactions unless we are sure they fit in disk */
@@ -457,8 +479,10 @@ int apfs_transaction_start(struct super_block *sb, struct apfs_max_ops maxops)
 		/* Commit what we have so far to flush the queues */
 		nx_trans->t_state |= APFS_NX_TRANS_FORCE_COMMIT;
 		err = apfs_transaction_commit(sb);
-		if (err)
+		if (err) {
+			apfs_err(sb, "commit failed");
 			goto fail;
+		}
 		return -ENOSPC;
 	}

@@ -473,16 +497,22 @@ int apfs_transaction_start(struct super_block *sb, struct apfs_max_ops maxops)
 		get_bh(vol_trans->t_old_omap_root.object.o_bh);

 		err = apfs_map_volume_super(sb, true /* write */);
-		if (err)
+		if (err) {
+			apfs_err(sb, "CoW failed for volume super");
 			goto fail;
+		}

 		/* TODO: don't copy these nodes for transactions that don't use them */
 		err = apfs_read_omap(sb, true /* write */);
-		if (err)
+		if (err) {
+			apfs_err(sb, "CoW failed for omap");
 			goto fail;
+		}
 		err = apfs_read_catalog(sb, true /* write */);
-		if (err)
+		if (err) {
+			apfs_err(sb, "Cow failed for catalog");
 			goto fail;
+		}
 	}

 	nx_trans->t_starts_count++;
@@ -577,8 +607,10 @@ int apfs_transaction_flush_all_inodes(struct super_block *sb)
 		nx_trans->t_state = 0;

 		/* Transaction aborted by ->evict_inode(), error code is lost */
-		if (sb->s_flags & SB_RDONLY)
+		if (sb->s_flags & SB_RDONLY) {
+			apfs_err(sb, "abort during inode eviction");
 			return -EROFS;
+		}
 	}

 	return err;
@@ -602,8 +634,10 @@ static int apfs_transaction_commit_nx(struct super_block *sb)

 	/* Before committing the bhs, write all inode metadata to them */
 	err = apfs_transaction_flush_all_inodes(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to flush all inodes");
 		return err;
+	}

 	/*
 	 * Now that nothing else will be freed, flush the last update to the
@@ -611,8 +645,10 @@ static int apfs_transaction_commit_nx(struct super_block *sb)
 	 */
 	if (sm->sm_free_cache_base) {
 		err = apfs_free_queue_insert_nocache(sb, sm->sm_free_cache_base, sm->sm_free_cache_blkcnt);
-		if (err)
+		if (err) {
+			apfs_err(sb, "fq cache flush failed (0x%llx-0x%llx)", sm->sm_free_cache_base, sm->sm_free_cache_blkcnt);
 			return err;
+		}
 		sm->sm_free_cache_base = sm->sm_free_cache_blkcnt = 0;
 	}

@@ -639,8 +675,10 @@ static int apfs_transaction_commit_nx(struct super_block *sb)
 		apfs_submit_bh(REQ_OP_WRITE, REQ_SYNC, bh);
 	}
 	err = apfs_checkpoint_end(sb);
-	if (err)
+	if (err) {
+		apfs_err(sb, "failed to end the checkpoint");
 		return err;
+	}

 	/* Success: forget the old container and volume superblocks */
 	brelse(nx_trans->t_old_msb);
@@ -750,7 +788,7 @@ int apfs_transaction_commit(struct super_block *sb)
 	if (apfs_transaction_need_commit(sb)) {
 		err = apfs_transaction_commit_nx(sb);
 		if (err) {
-			apfs_warn(sb, "transaction commit failed");
+			apfs_err(sb, "transaction commit failed");
 			return err;
 		}
 	}
@@ -858,7 +896,7 @@ void apfs_transaction_abort(struct super_block *sb)

 	ASSERT(nx_trans->t_old_msb);
 	nx_trans->t_state = 0;
-	apfs_warn(sb, "aborting transaction");
+	apfs_err(sb, "aborting transaction");

 	--nxi->nx_xid;
 	list_for_each_entry_safe(bhi, tmp, &nx_trans->t_buffers, list) {
@@ -23,32 +23,43 @@
 static int apfs_xattr_from_query(struct apfs_query *query,
 				 struct apfs_xattr *xattr)
 {
+	struct super_block *sb = query->node->object.sb;
 	struct apfs_xattr_val *xattr_val;
 	struct apfs_xattr_key *xattr_key;
 	char *raw = query->node->object.data;
 	int datalen = query->len - sizeof(*xattr_val);
 	int namelen = query->key_len - sizeof(*xattr_key);

-	if (namelen < 1 || datalen < 0)
+	if (namelen < 1 || datalen < 0) {
+		apfs_err(sb, "bad length of name (%d) or data (%d)", namelen, datalen);
 		return -EFSCORRUPTED;
+	}

 	xattr_val = (struct apfs_xattr_val *)(raw + query->off);
 	xattr_key = (struct apfs_xattr_key *)(raw + query->key_off);

-	if (namelen != le16_to_cpu(xattr_key->name_len))
+	if (namelen != le16_to_cpu(xattr_key->name_len)) {
+		apfs_err(sb, "inconsistent name length (%d vs %d)", namelen, le16_to_cpu(xattr_key->name_len));
 		return -EFSCORRUPTED;
+	}

 	/* The xattr name must be NULL-terminated */
-	if (xattr_key->name[namelen - 1] != 0)
+	if (xattr_key->name[namelen - 1] != 0) {
+		apfs_err(sb, "null termination missing");
 		return -EFSCORRUPTED;
+	}

 	xattr->has_dstream = le16_to_cpu(xattr_val->flags) &
 			     APFS_XATTR_DATA_STREAM;

-	if (xattr->has_dstream && datalen != sizeof(struct apfs_xattr_dstream))
+	if (xattr->has_dstream && datalen != sizeof(struct apfs_xattr_dstream)) {
+		apfs_err(sb, "bad data length (%d)", datalen);
 		return -EFSCORRUPTED;
-	if (!xattr->has_dstream && datalen != le16_to_cpu(xattr_val->xdata_len))
+	}
+	if (!xattr->has_dstream && datalen != le16_to_cpu(xattr_val->xdata_len)) {
+		apfs_err(sb, "inconsistent data length (%d vs %d)", datalen, le16_to_cpu(xattr_val->xdata_len));
 		return -EFSCORRUPTED;
+	}

 	xattr->name = xattr_key->name;
 	xattr->name_len = namelen - 1; /* Don't count the NULL termination */
@@ -113,7 +124,9 @@ static int apfs_xattr_extents_read(struct inode *parent,
 	length = dstream->ds_size;
 	if (length < 0 || length < dstream->ds_size) {
 		/* TODO: avoid overflow here for huge compressed files */
-		return -E2BIG;
+		apfs_warn(sb, "xattr is too big to read on linux (0x%llx)", dstream->ds_size);
+		ret = -E2BIG;
+		goto out;
 	}

 	if (!buffer) {
@@ -144,12 +157,14 @@ static int apfs_xattr_extents_read(struct inode *parent,
 			goto out;
 		if (bno == 0) {
 			/* No holes in xattr dstreams, I believe */
+			apfs_err(sb, "xattr dstream has a hole");
 			ret = -EFSCORRUPTED;
 			goto out;
 		}

 		bhs[i] = __getblk_gfp(APFS_NXI(sb)->nx_bdev, bno, sb->s_blocksize, __GFP_MOVABLE);
 		if (!bhs[i]) {
+			apfs_err(sb, "failed to map block 0x%llx", bno);
 			ret = -EIO;
 			goto out;
 		}
@@ -167,6 +182,7 @@ static int apfs_xattr_extents_read(struct inode *parent,

 		wait_on_buffer(bhs[i]);
 		if (!buffer_uptodate(bhs[i])) {
+			apfs_err(sb, "failed to read a block");
 			ret = -EIO;
 			goto out;
 		}
@@ -260,12 +276,15 @@ int ____apfs_xattr_get(struct inode *inode, const char *name, void *buffer,
 	query->flags |= APFS_QUERY_CAT | APFS_QUERY_EXACT;

 	ret = apfs_btree_query(sb, &query);
-	if (ret)
+	if (ret) {
+		if (ret != -ENODATA)
+			apfs_err(sb, "query failed for id 0x%llx (%s)", cnid, name);
 		goto done;
+	}

 	ret = apfs_xattr_from_query(query, &xattr);
 	if (ret) {
-		apfs_alert(sb, "bad xattr record in inode 0x%llx", cnid);
+		apfs_err(sb, "bad xattr record in inode 0x%llx", cnid);
 		goto done;
 	}

@@ -300,8 +319,10 @@ static int apfs_xattr_get(struct inode *inode, const char *name, void *buffer, s
 	down_read(&nxi->nx_big_sem);
 	ret = __apfs_xattr_get(inode, name, buffer, size);
 	up_read(&nxi->nx_big_sem);
-	if (ret > XATTR_SIZE_MAX)
+	if (ret > XATTR_SIZE_MAX) {
+		apfs_warn(inode->i_sb, "xattr is too big to read on linux (%d)", ret);
 		return -E2BIG;
+	}
 	return ret;
 }

@@ -327,8 +348,10 @@ static int apfs_delete_xattr(struct apfs_query *query)
 	int err;

 	err = apfs_xattr_from_query(query, &xattr);
-	if (err)
+	if (err) {
+		apfs_err(sb, "bad xattr record");
 		return err;
+	}

 	if (!xattr.has_dstream)
 		return apfs_btree_remove(query);
@@ -344,9 +367,13 @@ static int apfs_delete_xattr(struct apfs_query *query)
 	 * really need to add some assertions (TODO).
 	 */
 	err = apfs_btree_remove(query);
-	if (err)
+	if (err) {
+		apfs_err(sb, "removal failed");
 		goto fail;
+	}
 	err = apfs_truncate(dstream, 0);
+	if (err)
+		apfs_err(sb, "truncation failed for dstream 0x%llx", dstream->ds_id);

 fail:
 	kfree(dstream);
@@ -381,12 +408,16 @@ static int apfs_delete_any_xattr(struct inode *inode)
 	if (ret) {
 		if (ret == -ENODATA)
 			ret = 0; /* No more xattrs, we are done */
+		else
+			apfs_err(sb, "query failed for ino 0x%llx", apfs_ino(inode));
 		goto out;
 	}

 	ret = apfs_delete_xattr(query);
 	if (!ret)
 		ret = -EAGAIN;
+	else
+		apfs_err(sb, "xattr deletion failed");

 out:
 	apfs_free_query(query);
@@ -434,7 +465,7 @@ static int apfs_build_xattr_key(const char *name, u64 ino, struct apfs_xattr_key

 	apfs_key_set_hdr(APFS_TYPE_XATTR, ino, key);
 	key->name_len = cpu_to_le16(namelen);
-	strcpy(key->name, name);
+	strscpy(key->name, name, namelen);

 	*key_p = key;
 	return key_len;
@@ -531,10 +562,13 @@ static struct apfs_dstream_info *apfs_create_xattr_dstream(struct super_block *s
 		u64 bno;

 		err = apfs_dstream_get_new_bno(dstream, i, &bno);
-		if (err)
+		if (err) {
+			apfs_err(sb, "failed to get new block in dstream 0x%llx", dstream->ds_id);
 			goto fail;
+		}
 		bh = apfs_sb_bread(sb, bno);
 		if (!bh) {
+			apfs_err(sb, "failed to read new block");
 			err = -EIO;
 			goto fail;
 		}
@@ -556,8 +590,10 @@ static struct apfs_dstream_info *apfs_create_xattr_dstream(struct super_block *s
 	}

 	err = apfs_flush_extent_cache(dstream);
-	if (err)
+	if (err) {
+		apfs_err(sb, "extent cache flush failed for dstream 0x%llx", dstream->ds_id);
 		goto fail;
+	}
 	return dstream;

 fail:
@@ -580,8 +616,10 @@ static int apfs_xattr_dstream_from_query(struct apfs_query *query, struct apfs_d
 	int err;

 	err = apfs_xattr_from_query(query, &xattr);
-	if (err)
+	if (err) {
+		apfs_err(sb, "bad xattr record");
 		return err;
+	}

 	if (xattr.has_dstream) {
 		dstream = kzalloc(sizeof(*dstream), GFP_KERNEL);
@@ -620,8 +658,10 @@ int apfs_xattr_set(struct inode *inode, const char *name, const void *value,

 	if (size > APFS_XATTR_MAX_EMBEDDED_SIZE) {
 		dstream = apfs_create_xattr_dstream(sb, value, size);
-		if (IS_ERR(dstream))
+		if (IS_ERR(dstream)) {
+			apfs_err(sb, "failed to set xattr dstream for ino 0x%llx", apfs_ino(inode));
 			return PTR_ERR(dstream);
+		}
 	}

 	apfs_init_xattr_key(cnid, name, &key);
@@ -636,21 +676,27 @@ int apfs_xattr_set(struct inode *inode, const char *name, const void *value,

 	ret = apfs_btree_query(sb, &query);
 	if (ret) {
-		if (ret != -ENODATA)
+		if (ret != -ENODATA) {
+			apfs_err(sb, "query failed for id 0x%llx (%s)", cnid, name);
 			goto done;
-		else if (flags & XATTR_REPLACE)
+		} else if (flags & XATTR_REPLACE) {
 			goto done;
+		}
 	} else if (flags & XATTR_CREATE) {
 		ret = -EEXIST;
 		goto done;
 	} else if (!value) {
 		ret = apfs_delete_xattr(query);
+		if (ret)
+			apfs_err(sb, "xattr deletion failed");
 		goto done;
 	} else {
 		/* Remember the old dstream to clean it up later */
 		ret = apfs_xattr_dstream_from_query(query, &old_dstream);
-		if (ret)
+		if (ret) {
+			apfs_err(sb, "failed to get the old dstream");
 			goto done;
+		}
 	}

 	key_len = apfs_build_xattr_key(name, cnid, &raw_key);
@@ -676,11 +722,16 @@ int apfs_xattr_set(struct inode *inode, const char *name, const void *value,
 		ret = apfs_btree_insert(query, raw_key, key_len, raw_val, val_len);
 	else
 		ret = apfs_btree_replace(query, raw_key, key_len, raw_val, val_len);
-	if (ret)
+	if (ret) {
+		apfs_err(sb, "insertion/update failed for id 0x%llx (%s)", cnid, name);
 		goto done;
+	}

-	if (old_dstream)
+	if (old_dstream) {
 		ret = apfs_truncate(old_dstream, 0);
+		if (ret)
+			apfs_err(sb, "truncation failed for dstream 0x%llx", old_dstream->ds_id);
+	}

 done:
 	kfree(dstream);
@@ -699,11 +750,16 @@ int APFS_XATTR_SET_MAXOPS(void)
 static int apfs_xattr_osx_set(const struct xattr_handler *handler,
 	      struct dentry *unused, struct inode *inode, const char *name,
 	      const void *value, size_t size, int flags)
-#else
+#elif LINUX_VERSION_CODE < KERNEL_VERSION(6, 3, 0)
 static int apfs_xattr_osx_set(const struct xattr_handler *handler,
 		  struct user_namespace *mnt_userns, struct dentry *unused,
 		  struct inode *inode, const char *name, const void *value,
 		  size_t size, int flags)
+#else
+static int apfs_xattr_osx_set(const struct xattr_handler *handler,
+		  struct mnt_idmap *idmap, struct dentry *unused,
+		  struct inode *inode, const char *name, const void *value,
+		  size_t size, int flags)
 #endif
 {
 	struct super_block *sb = inode->i_sb;
@@ -776,12 +832,14 @@ ssize_t apfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 			ret = size - free;
 			break;
 		}
-		if (ret)
+		if (ret) {
+			apfs_err(sb, "query failed for id 0x%llx", cnid);
 			break;
+		}

 		ret = apfs_xattr_from_query(query, &xattr);
 		if (ret) {
-			apfs_alert(sb, "bad xattr key in inode %llx", cnid);
+			apfs_err(sb, "bad xattr key in inode %llx", cnid);
 			break;
 		}
Author	SHA1	Message	Date
Ernesto A. Fernández	af0671f58f	0.3.4 This release fixes the build for the Linux 6.5 release candidate, and it should also fix a long-standing mmap bug in Linux 5.14 and above, which resulted in null pointer dereference. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-08-14 23:50:19 -03:00
Ernesto A. Fernández	740d7db44b	Fix mmap for kernels 5.14 and above Adamantinum reports trouble while attempting to use apfs as root with kernel version 6.4.8: https://github.com/linux-apfs/linux-apfs-rw/issues/50 His callstack shows an npd in mmap, and the bug can be easily reproduced by generic/029, but not in kernel version 5.3, where I usually run my tests. Via bisection I tracked the problem back to kernel commit 0af573780b0b ("mm: require ->set_page_dirty to be explicitly wired up"). Starting with kernel 5.14, the ->set_page_dirty() address space method gets called unconditionally, without checking for null first, so set it explicitly. Kernel 5.18 replaced ->set_page_dirty() with ->dirty_folio(), so take care of that as well. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-08-14 19:50:22 -03:00
Ernesto A. Fernández	bc2be91bb4	Update FMODE_* stuff for the 6.5 kernel The build is broken for the Linux 6.5 release candidate: https://github.com/linux-apfs/linux-apfs-rw/issues/49 The fmode_t type can no longer be used for block open flags, and we must switch to blk_mode_t instead. FMODE_EXCL is no longer needed, since just having a holder already implies it, but this requires a change to the blkdev_put() api. There is also a new argument to blkdev_get_by_path() which can be safely ignored. And finally, sb->s_mode is gone, but it doesn't seem to make any difference. Update all the code to the new apis. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-08-08 20:58:11 -03:00
Ernesto A. Fernández	5c4773c036	Convert all strcpy() to strscpy() The build appears to be broken for some configurations on the Linux 6.5 release candidate: https://github.com/linux-apfs/linux-apfs-rw/issues/49 Some sort of static overflow check is going on for strcpy(), and several of my calls are triggering false positives. Just be safe and switch them all to strscpy(). The qstr stuff in particular looked a bit too weird anyway. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-08-08 19:14:10 -03:00
Ernesto A. Fernández	1e3fa28c4f	Increase limit for compressed size of files A recent cryptex image contains a file with a compressed size above the current 128Mb limit. This limit exists because of vmalloc(), and it can be increased (at least for 64-bit archs). Do that for now, but I really should try to restructure the code to use smaller kmalloc() allocations instead. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-06-07 20:40:53 -03:00
Ernesto A. Fernández	d4799475db	0.3.3 This release fixes builds for kernels below 5.3, which have all been broken for a while. So far development has only been focused on Linux 5.3, and I've relied on reporters to find out about issues on other versions. From now on I will at least run builds for a range of kernels before each release, so hopefully this won't happen again. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-05-24 23:05:25 -03:00
Ernesto A. Fernández	c54e3a7423	Silence b_blocknr width warnings on old kernels While fixing the build for old kernels, I noticed that in some of them you get a warning when you prink a buffer head's b_blocknr as 0x%llx. I haven't checked but I'm guessing that, at some point, sector_t on 64-bit archs went from being 'unsigned long' to 'unsigned long long', so these warnings went away. Anyway, just cast b_blocknr before printing it in all kernels. At some point I do need to attempt a 32-bit build though. It's been a long time, and I'm sure there will be much worse problems than this one. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-05-19 18:49:38 -03:00
Ernesto A. Fernández	b185ce13bd	Fix builds before generic_copy_file_range() Even with the previous patch, builds are still broken for all kernels before 5.2. The problem is that generic_copy_file_range() wasn't introduced until Linux 5.3. The good news is that we don't actually need it for older kernels: as I explained in the commit message for the patch that broke this, we can just returning an error code from apfs_remap_file_range(). Fixes: `396650b056` ("Don't let copy_file_range() use clones") Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-05-19 18:31:51 -03:00
Ernesto A. Fernández	42d70a8997	Fix build for kernels with separate clone/dedupe Luflosi reports that the build is broken once again for Linux 4.14 and 4.19: https://github.com/linux-apfs/linux-apfs-rw/issues/43 The problem here is that the clone and dedupe operations used to be implemented with separate methods. Since Linux 4.20, they both use the same ->remap_file_range(), with some flags passed to tell them apart. So when I implemented clones I used this new version and broke the build for the old ones. Fix it now. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-05-19 18:31:51 -03:00
Ernesto A. Fernández	97ba9b0dc8	0.3.2 This release improves error messages, which will hopefully make it easier to communicate with bug reporters. A number of bugs are also addressed, most importantly a missing check on the node count limit for the free queues, which could trigger reports of corruption in some rare cases (no data loss though, as far as I can see). Support is added for the 6.3 kernel version, courtesy of Woody Suwalski. I was hoping to wait until encryption was ready before making a release, but I'm not finding much time for apfs these days so that could take a while. In the meantime, it's better to get this stuff out the door. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-05-16 17:57:01 -03:00
Ernesto A. Fernández	8b99af84d1	Try to avoid failing insertion on fragmented nodes I'm getting somewhat regular failures on generic/112 because the ip free queue for the test image has a one-node limit, and it sometimes gets full. The thing is, the node actually has plenty of room, but it's all in the key free list, so I can't allocate values. From now on, if an insertion fails with ENOSPC, check the available room and defragment the node if it should be enough. Then retry the insertion instead of jumping straight to a split. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-17 20:05:26 -03:00
Ernesto A. Fernández	3a605ec8ff	Don't ignore error code in apfs_flush_fq_rec() The previous patch was intended to trigger an immediate abort when a free queue violated its own node limit. But I managed to trigger this event again with generic/112, and to my surprise there were several operations in dmesg before the abort finally happened. The problem here is in apfs_flush_fq_rec(): when apfs_main_free() fails (in this case because the ip free queue is full), the error code is reported but not bubbled up. This is a mistake of course, so fix it. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-12 17:49:12 -03:00
Ernesto A. Fernández	ccefdd13d8	Don't allow free queues to exceed their node limit Free queues have a node limit that is set by the mkfs. Very rarely, generic/112 manages to break this limit, and corruption is reported. Preventing corruption is always the number one priority, so add a check for this limit after every free queue insertion so that we can abort immediately when it fails. Remember though, that there is a deeper issue here: either the btrees are becoming too fragmented, or the flushes are not frequent enough. The queues should never fill like this. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-12 16:47:55 -03:00
Ernesto A. Fernández	5beaaae75c	Fix out-of-bounds read on snapshot ioctl Don't call strlen() on the name argument of the ioctl, because it may not be null-terminated. I'm not sure what the consequences of this are, but I don't think it should be exploitable. Use strnlen() instead. Also move the length check outside the transaction: we don't want simple user mistakes triggering aborts. And fix the returned error code: there is no on-disk corruption going on, just user error. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-05 23:06:22 -03:00
Ernesto A. Fernández	0f47fc762a	Fix memory leak on xattr length overflow Always free the allocated dstream in apfs_xattr_extents_read() before returning. Fixes: `362c4e32ab` ("Allow internal reads of huge xattrs") Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-05 22:21:53 -03:00
Ernesto A. Fernández	d4797823ea	Improve error reporting The driver is much closer to being usable, so I might start getting subtler bug reports soon. To make them easier to handle, put error messages all over the place. I should have done this from the beginning, but I guess I didn't fully understand the need back then. From now my general policy will be to use apfs_warn() for user errors or unsupported features; apfs_err() for things that are probably corruption or io errors; and apfs_alert() for things that are most likely bugs. These last two should be rare, so the same error/alert will be thrown by several layers in the callstack to provide as much information as possible. Be careful and don't flood the console on normal situations. Also, make messages with a log level lower than warning output their function name and line number, which I think will help debugging more than the actual messages. Signed-off-by: Ernesto A. Fernández <ernesto@corellium.com>	2023-04-05 21:59:24 -03:00
Woody Suwalski	24daddc890	Changes needed to build on kernel 6.3	2023-03-24 15:12:47 -03:00