Merge tag 'mm-hotfixes-stable-2025-03-17-20-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc hotfixes from Andrew Morton:
 "15 hotfixes. 7 are cc:stable and the remainder address post-6.13
  issues or aren't considered necessary for -stable kernels.

  13 are for MM and the other two are for squashfs and procfs.

  All are singletons. Please see the individual changelogs for details"

* tag 'mm-hotfixes-stable-2025-03-17-20-09' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/page_alloc: fix memory accept before watermarks gets initialized
  mm: decline to manipulate the refcount on a slab page
  memcg: drain obj stock on cpu hotplug teardown
  mm/huge_memory: drop beyond-EOF folios with the right number of refs
  selftests/mm: run_vmtests.sh: fix half_ufd_size_MB calculation
  mm: fix error handling in __filemap_get_folio() with FGP_NOWAIT
  mm: memcontrol: fix swap counter leak from offline cgroup
  mm/vma: do not register private-anon mappings with khugepaged during mmap
  squashfs: fix invalid pointer dereference in squashfs_cache_delete
  mm/migrate: fix shmem xarray update during migration
  mm/hugetlb: fix surplus pages in dissolve_free_huge_page()
  mm/damon/core: initialize damos->walk_completed in damon_new_scheme()
  mm/damon: respect core layer filters' allowance decision on ops layer
  filemap: move prefaulting out of hot write path
  proc: fix UAF in proc_get_inode()

fs/proc/generic.c

@@ -559,10 +559,16 @@ struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
 	return p;
 }
 
-static inline void pde_set_flags(struct proc_dir_entry *pde)
+static void pde_set_flags(struct proc_dir_entry *pde)
 {
 	if (pde->proc_ops->proc_flags & PROC_ENTRY_PERMANENT)
 		pde->flags |= PROC_ENTRY_PERMANENT;
+	if (pde->proc_ops->proc_read_iter)
+		pde->flags |= PROC_ENTRY_proc_read_iter;
+#ifdef CONFIG_COMPAT
+	if (pde->proc_ops->proc_compat_ioctl)
+		pde->flags |= PROC_ENTRY_proc_compat_ioctl;
+#endif
 }
 
 struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
@@ -626,6 +632,7 @@ struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode,
 	p->proc_ops = &proc_seq_ops;
 	p->seq_ops = ops;
 	p->state_size = state_size;
+	pde_set_flags(p);
 	return proc_register(parent, p);
 }
 EXPORT_SYMBOL(proc_create_seq_private);
@@ -656,6 +663,7 @@ struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
 		return NULL;
 	p->proc_ops = &proc_single_ops;
 	p->single_show = show;
+	pde_set_flags(p);
 	return proc_register(parent, p);
 }
 EXPORT_SYMBOL(proc_create_single_data);

fs/proc/inode.c

@@ -656,13 +656,13 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
 
 	if (S_ISREG(inode->i_mode)) {
 		inode->i_op = de->proc_iops;
-		if (de->proc_ops->proc_read_iter)
+		if (pde_has_proc_read_iter(de))
 			inode->i_fop = &proc_iter_file_ops;
 		else
 			inode->i_fop = &proc_reg_file_ops;
 #ifdef CONFIG_COMPAT
-		if (de->proc_ops->proc_compat_ioctl) {
-			if (de->proc_ops->proc_read_iter)
+		if (pde_has_proc_compat_ioctl(de)) {
+			if (pde_has_proc_read_iter(de))
 				inode->i_fop = &proc_iter_file_ops_compat;
 			else
 				inode->i_fop = &proc_reg_file_ops_compat;

fs/proc/internal.h

@@ -85,6 +85,20 @@ static inline void pde_make_permanent(struct proc_dir_entry *pde)
 	pde->flags |= PROC_ENTRY_PERMANENT;
 }
 
+static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde)
+{
+	return pde->flags & PROC_ENTRY_proc_read_iter;
+}
+
+static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde)
+{
+#ifdef CONFIG_COMPAT
+	return pde->flags & PROC_ENTRY_proc_compat_ioctl;
+#else
+	return false;
+#endif
+}
+
 extern struct kmem_cache *proc_dir_entry_cache;
 void pde_free(struct proc_dir_entry *pde);
 

fs/squashfs/cache.c

@@ -198,7 +198,7 @@ void squashfs_cache_delete(struct squashfs_cache *cache)
 {
 	int i, j;
 
-	if (cache == NULL)
+	if (IS_ERR(cache) || cache == NULL)
 		return;
 
 	for (i = 0; i < cache->entries; i++) {