When p9pdu_readf() is called with "s?d" attribute, it allocates a pointer
that will store a string. But when p9pdu_readf() fails while handling "d"
then this pointer will not be freed in p9_check_errors().
Fixes: 51a87c552d ("9p: rework client code to use new protocol support functions")
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Message-ID: <20231027030302.11927-1-hbh25y@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Use the constant to make the compiler happy about this warning:
net/9p/trans_xen.c: In function ‘xen_9pfs_front_changed’:
net/9p/trans_xen.c:444:39: warning: ‘%d’ directive writing between 1 and 11 bytes into a region of size 8 [-Wformat-overflow=]
444 | sprintf(str, "ring-ref%d", i);
| ^~
In function ‘xen_9pfs_front_init’,
inlined from ‘xen_9pfs_front_changed’ at net/9p/trans_xen.c:516:8,
inlined from ‘xen_9pfs_front_changed’ at net/9p/trans_xen.c:504:13:
net/9p/trans_xen.c:444:30: note: directive argument in the range [-2147483644, 2147483646]
444 | sprintf(str, "ring-ref%d", i);
| ^~~~~~~~~~~~
net/9p/trans_xen.c:444:17: note: ‘sprintf’ output between 10 and 20 bytes into a destination of size 16
444 | sprintf(str, "ring-ref%d", i);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/9p/trans_xen.c: In function ‘xen_9pfs_front_changed’:
net/9p/trans_xen.c:450:45: warning: ‘%d’ directive writing between 1 and 11 bytes into a region of size 2 [-Wformat-overflow=]
450 | sprintf(str, "event-channel-%d", i);
| ^~
In function ‘xen_9pfs_front_init’,
inlined from ‘xen_9pfs_front_changed’ at net/9p/trans_xen.c:516:8,
inlined from ‘xen_9pfs_front_changed’ at net/9p/trans_xen.c:504:13:
net/9p/trans_xen.c:450:30: note: directive argument in the range [-2147483644, 2147483646]
450 | sprintf(str, "event-channel-%d", i);
| ^~~~~~~~~~~~~~~~~~
net/9p/trans_xen.c:450:17: note: ‘sprintf’ output between 16 and 26 bytes into a destination of size 16
450 | sprintf(str, "event-channel-%d", i);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There is no change in logic: there only are a constant number of rings,
and there also already is a BUILD_BUG_ON that checks if that constant
goes over 9 as anything bigger would no longer fit the event-channel-%d
destination size.
In theory having that size as part of the struct means it could be
modified by another thread and makes the compiler lose track of possible
values for 'i' here, using the constant directly here makes it work.
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Message-ID: <20231025103445.1248103-3-asmadeus@codewreck.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
W=1 warns about null argument to kprintf:
In file included from fs/9p/xattr.c:12:
In function ‘v9fs_xattr_get’,
inlined from ‘v9fs_listxattr’ at fs/9p/xattr.c:142:9:
include/net/9p/9p.h:55:2: error: ‘%s’ directive argument is null
[-Werror=format-overflow=]
55 | _p9_debug(level, __func__, fmt, ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Use an empty string instead of :
- this is ok 9p-wise because p9pdu_vwritef serializes a null string
and an empty string the same way (one '0' word for length)
- since this degrades the print statements, add new single quotes for
xattr's name delimter (Old: "file = (null)", new: "file = ''")
Link: https://lore.kernel.org/r/20231008060138.517057-1-suhui@nfschina.com
Suggested-by: Su Hui <suhui@nfschina.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Acked-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Message-ID: <20231025103445.1248103-2-asmadeus@codewreck.org>
syzbot reported:
| BUG: KCSAN: data-race in p9_fd_create / p9_fd_create
|
| read-write to 0xffff888130fb3d48 of 4 bytes by task 15599 on cpu 0:
| p9_fd_open net/9p/trans_fd.c:842 [inline]
| p9_fd_create+0x210/0x250 net/9p/trans_fd.c:1092
| p9_client_create+0x595/0xa70 net/9p/client.c:1010
| v9fs_session_init+0xf9/0xd90 fs/9p/v9fs.c:410
| v9fs_mount+0x69/0x630 fs/9p/vfs_super.c:123
| legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
| vfs_get_tree+0x51/0x190 fs/super.c:1519
| do_new_mount+0x203/0x660 fs/namespace.c:3335
| path_mount+0x496/0xb30 fs/namespace.c:3662
| do_mount fs/namespace.c:3675 [inline]
| __do_sys_mount fs/namespace.c:3884 [inline]
| [...]
|
| read-write to 0xffff888130fb3d48 of 4 bytes by task 15563 on cpu 1:
| p9_fd_open net/9p/trans_fd.c:842 [inline]
| p9_fd_create+0x210/0x250 net/9p/trans_fd.c:1092
| p9_client_create+0x595/0xa70 net/9p/client.c:1010
| v9fs_session_init+0xf9/0xd90 fs/9p/v9fs.c:410
| v9fs_mount+0x69/0x630 fs/9p/vfs_super.c:123
| legacy_get_tree+0x74/0xd0 fs/fs_context.c:611
| vfs_get_tree+0x51/0x190 fs/super.c:1519
| do_new_mount+0x203/0x660 fs/namespace.c:3335
| path_mount+0x496/0xb30 fs/namespace.c:3662
| do_mount fs/namespace.c:3675 [inline]
| __do_sys_mount fs/namespace.c:3884 [inline]
| [...]
|
| value changed: 0x00008002 -> 0x00008802
Within p9_fd_open(), O_NONBLOCK is added to f_flags of the read and
write files. This may happen concurrently if e.g. mounting process
modifies the fd in another thread.
Mark the plain read-modify-writes as intentional data-races, with the
assumption that the result of executing the accesses concurrently will
always result in the same result despite the accesses themselves not
being atomic.
Reported-by: syzbot+e441aeeb422763cc5511@syzkaller.appspotmail.com
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/ZO38mqkS0TYUlpFp@elver.google.com
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Message-ID: <20231025103445.1248103-1-asmadeus@codewreck.org>
When a connection is cancelled by p9_conn_cancel(), all requests on it
should be cancelled---mark req->status as REQ_STATUS_ERROR. However,
because a race over m->err between p9_conn_cancel() and p9_fd_request(),
p9_fd_request might see the old value of m->err, think that the connection
is NOT cancelled, and then add new requests to this cancelled connection.
Fixing this issue by lock-protecting the check on m->err.
Signed-off-by: Sishuai Gong <sishuai.system@gmail.com>
Message-ID: <AA2DB53B-DFC7-4B88-9515-E4C9AFA6435D@gmail.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
IPV6_ADDRFORM socket option is evil, because it can change sock->ops
while other threads might read it. Same issue for sk->sk_family
being set to AF_INET.
Adding READ_ONCE() over sock->ops reads is needed for sockets
that might be impacted by IPV6_ADDRFORM.
Note that mptcp_is_tcpsk() can also overwrite sock->ops.
Adding annotations for all sk->sk_family reads will require
more patches :/
BUG: KCSAN: data-race in ____sys_sendmsg / do_ipv6_setsockopt
write to 0xffff888109f24ca0 of 8 bytes by task 4470 on cpu 0:
do_ipv6_setsockopt+0x2c5e/0x2ce0 net/ipv6/ipv6_sockglue.c:491
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
udpv6_setsockopt+0x95/0xa0 net/ipv6/udp.c:1690
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3663
__sys_setsockopt+0x1c3/0x230 net/socket.c:2273
__do_sys_setsockopt net/socket.c:2284 [inline]
__se_sys_setsockopt net/socket.c:2281 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2281
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
read to 0xffff888109f24ca0 of 8 bytes by task 4469 on cpu 1:
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
____sys_sendmsg+0x349/0x4c0 net/socket.c:2503
___sys_sendmsg net/socket.c:2557 [inline]
__sys_sendmmsg+0x263/0x500 net/socket.c:2643
__do_sys_sendmmsg net/socket.c:2672 [inline]
__se_sys_sendmmsg net/socket.c:2669 [inline]
__x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0xffffffff850e32b8 -> 0xffffffff850da890
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4469 Comm: syz-executor.1 Not tainted 6.4.0-rc5-syzkaller-00313-g4c605260bc60 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230808135809.2300241-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The 9p code for some reason used to initialize variables outside of the
declaration, e.g. instead of just initializing the variable like this:
int retval = 0
We would be doing this:
int retval;
retval = 0;
This is perfectly fine and the compiler will just optimize dead stores
anyway, but scan-build seems to think this is a problem and there are
many of these warnings making the output of scan-build full of such
warnings:
fs/9p/vfs_inode.c:916:2: warning: Value stored to 'retval' is never read [deadcode.DeadStores]
retval = 0;
^ ~
I have no strong opinion here, but if we want to regularly run
scan-build we should fix these just to silence the messages.
I've confirmed these all are indeed ok to remove.
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Fix the following scan-build warning:
net/9p/trans_virtio.c:504:3: warning: Value stored to 'in' is never read [deadcode.DeadStores]
in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM,
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I'm honestly not 100% sure about this one; I'm tempted to think we
could (should?) just check the return value of pack_sg_list_p to skip
the in_sgs++ and setting sgs[] if it didn't process anything, but I'm
not sure it should ever happen so this is probably fine as is.
Just removing the assignment at least makes it clear the return value
isn't used, so it's an improvement in terms of readability.
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Similarly to the previous patch: offs can be used in handle_rerrors
without initializing on small payloads; in this case handle_rerrors will
not use it because of the size check, but it doesn't hurt to make sure
it is zero to please scan-build.
This fixes the following warning:
net/9p/trans_virtio.c:539:3: warning: 3rd function call argument is an uninitialized value [core.CallAndMessage]
handle_rerror(req, in_hdr_len, offs, in_pages);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
handle_rerror can dereference the pages pointer, but it is not
necessarily set for small payloads.
In practice these should be filtered out by the size check, but
might as well double-check explicitly.
This fixes the following scan-build warnings:
net/9p/trans_virtio.c:401:24: warning: Dereference of null pointer [core.NullDereference]
memcpy_from_page(to, *pages++, offs, n);
^~~~~~~~
net/9p/trans_virtio.c:406:23: warning: Dereference of null pointer (loaded from variable 'pages') [core.NullDereference]
memcpy_from_page(to, *pages, offs, size);
^~~~~~
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Pull networking fixes from Jakub Kicinski:
"Including fixes from netfilter.
Current release - regressions:
- sched: act_pedit: free pedit keys on bail from offset check
Current release - new code bugs:
- pds_core:
- Kconfig fixes (DEBUGFS and AUXILIARY_BUS)
- fix mutex double unlock in error path
Previous releases - regressions:
- sched: cls_api: remove block_cb from driver_list before freeing
- nf_tables: fix ct untracked match breakage
- eth: mtk_eth_soc: drop generic vlan rx offload
- sched: flower: fix error handler on replace
Previous releases - always broken:
- tcp: fix skb_copy_ubufs() vs BIG TCP
- ipv6: fix skb hash for some RST packets
- af_packet: don't send zero-byte data in packet_sendmsg_spkt()
- rxrpc: timeout handling fixes after moving client call connection
to the I/O thread
- ixgbe: fix panic during XDP_TX with > 64 CPUs
- igc: RMW the SRRCTL register to prevent losing timestamp config
- dsa: mt7530: fix corrupt frames using TRGMII on 40 MHz XTAL MT7621
- r8152:
- fix flow control issue of RTL8156A
- fix the poor throughput for 2.5G devices
- move setting r8153b_rx_agg_chg_indicate() to fix coalescing
- enable autosuspend
- ncsi: clear Tx enable mode when handling a Config required AEN
- octeontx2-pf: macsec: fixes for CN10KB ASIC rev
Misc:
- 9p: remove INET dependency"
* tag 'net-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
net: bcmgenet: Remove phy_stop() from bcmgenet_netif_stop()
pds_core: fix mutex double unlock in error path
net/sched: flower: fix error handler on replace
Revert "net/sched: flower: Fix wrong handle assignment during filter change"
net/sched: flower: fix filter idr initialization
net: fec: correct the counting of XDP sent frames
bonding: add xdp_features support
net: enetc: check the index of the SFI rather than the handle
sfc: Add back mailing list
virtio_net: suppress cpu stall when free_unused_bufs
ice: block LAN in case of VF to VF offload
net: dsa: mt7530: fix network connectivity with multiple CPU ports
net: dsa: mt7530: fix corrupt frames using trgmii on 40 MHz XTAL MT7621
9p: Remove INET dependency
netfilter: nf_tables: fix ct untracked match breakage
af_packet: Don't send zero-byte data in packet_sendmsg_spkt().
igc: read before write to SRRCTL register
pds_core: add AUXILIARY_BUS and NET_DEVLINK to Kconfig
pds_core: remove CONFIG_DEBUG_FS from makefile
ionic: catch failure from devlink_alloc
...
Pull 9p updates from Eric Van Hensbergen:
"This includes a number of patches that didn't quite make the cut last
merge window while we addressed some outstanding issues and review
comments. It includes some new caching modes for those that only want
readahead caches and reworks how we do writeback caching so we are not
keeping extra references around which both causes performance problems
and uses lots of additional resources on the server.
It also includes a new flag to force disabling of xattrs which can
also cause major performance issues, particularly if the underlying
filesystem on the server doesn't support them.
Finally it adds a couple of additional mount options to better support
directio and enabling caches when the server doesn't support
qid.version.
There was one late-breaking bug report that has also been included as
its own patch where I forgot to propagate an embarassing bit-logic fix
to the various variations of open"
* tag '9p-6.4-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
fs/9p: Fix bit operation logic error
fs/9p: Rework cache modes and add new options to Documentation
fs/9p: remove writeback fid and fix per-file modes
fs/9p: Add new mount modes
9p: Add additional debug flags and open modes
fs/9p: allow disable of xattr support on mount
fs/9p: Remove unnecessary superblock flags
fs/9p: Consolidate file operations and add readahead and writeback
9pfs can run over assorted transports, so it doesn't have an INET
dependency. Drop it and remove the includes of linux/inet.h.
NET_9P_FD/trans_fd.o builds without INET or UNIX and is usable over
plain file descriptors. However, tcp and unix functionality is still
built and would generate runtime failures if used. Add imply INET and
UNIX to NET_9P_FD, so functionality is enabled by default but can still
be explicitly disabled.
This allows configuring 9pfs over Xen with INET and UNIX disabled.
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In xen_9pfs_front_probe, it calls xen_9pfs_front_alloc_dataring
to init priv->rings and bound &ring->work with p9_xen_response.
When it calls xen_9pfs_front_event_handler to handle IRQ requests,
it will finally call schedule_work to start the work.
When we call xen_9pfs_front_remove to remove the driver, there
may be a sequence as follows:
Fix it by finishing the work before cleanup in xen_9pfs_front_free.
Note that, this bug is found by static analysis, which might be
false positive.
CPU0 CPU1
|p9_xen_response
xen_9pfs_front_remove|
xen_9pfs_front_free|
kfree(priv) |
//free priv |
|p9_tag_lookup
|//use priv->client
Fixes: 71ebd71921 ("xen/9pfs: connect to the backend")
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Add some additional debug flags to assist with debugging
cache changes. Also add some additional open modes so we
can track cache state in fids more directly.
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Pull 9p updates from Eric Van Hensbergen:
- some fixes and cleanup setting up for a larger set of performance
patches I've been working on
- a contributed fixes relating to 9p/rdma
- some contributed fixes relating to 9p/xen
* tag '9p-6.3-for-linus-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
fs/9p: fix error reporting in v9fs_dir_release
net/9p: fix bug in client create for .L
9p/rdma: unmap receive dma buffer in rdma_request()/post_recv()
9p/xen: fix connection sequence
9p/xen: fix version parsing
fs/9p: Expand setup of writeback cache to all levels
net/9p: Adjust maximum MSIZE to account for p9 header
We are supposed to set fid->mode to reflect the flags
that were used to open the file. We were actually setting
it to the creation mode which is the default perms of the
file not the flags the file was opened with.
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
When connecting the Xen 9pfs frontend to the backend, the "versions"
Xenstore entry written by the backend is parsed in a wrong way.
The "versions" entry is defined to contain the versions supported by
the backend separated by commas (e.g. "1,2"). Today only version "1"
is defined. Unfortunately the frontend doesn't look for "1" being
listed in the entry, but it is expecting the entry to have the value
"1".
This will result in failure as soon as the backend will support e.g.
versions "1" and "2".
Fix that by scanning the entry correctly.
Link: https://lkml.kernel.org/r/20230130113036.7087-2-jgross@suse.com
Fixes: 71ebd71921 ("xen/9pfs: connect to the backend")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Add maximum p9 header size to MSIZE to make sure we can
have page aligned data.
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
Reviewed-by: Dominique Martinet <asmadeus@codewreck.org>
Pull xen fixes from Juergen Gross:
- two cleanup patches
- a fix of a memory leak in the Xen pvfront driver
- a fix of a locking issue in the Xen hypervisor console driver
* tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pvcalls: free active map buffer on pvcalls_front_free_map
hvc/xen: lock console list traversal
x86/xen: Remove the unused function p2m_index()
xen: make remove callback of xen driver void returned
Pull 9p updates from Dominique Martinet:
- improve p9_check_errors to check buffer size instead of msize when
possible (e.g. not zero-copy)
- some more syzbot and KCSAN fixes
- minor headers include cleanup
* tag '9p-for-6.2-rc1' of https://github.com/martinetd/linux:
9p/client: fix data race on req->status
net/9p: fix response size check in p9_check_errors()
net/9p: distinguish zero-copy requests
9p/xen: do not memcpy header into req->rc
9p: set req refcount to zero to avoid uninitialized usage
9p/net: Remove unneeded idr.h #include
9p/fs: Remove unneeded idr.h #include
