commit 28e0947651 upstream.
We were decrementing the count of open files on server twice
for the case where we were closing cached directories.
Fixes: 8e843bf38f ("cifs: return a single-use cfid if we did not get a lease")
Cc: stable@vger.kernel.org
Acked-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 173217bd73 upstream.
In the current implementation, CIFS close sends a close to the
server and does not check for the success of the server close.
This patch adds functionality to check for server close return
status and retries in case of an EBUSY or EAGAIN error.
This can help avoid handle leaks
Cc: stable@vger.kernel.org
Signed-off-by: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 64cc377b76 ]
The code to check for replay is not just -EAGAIN. In some
cases, the send request or receive response may result in
network errors, which we're now mapping to -ECONNABORTED.
This change introduces a helper function which checks
if the error returned in one of the above two errors.
And all checks for replays will now use this helper.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 936eba9cfb ]
open_cached_dir today selects ses->server a.k.a primary channel
to send requests. When multichannel is used, the primary
channel maybe down. So it does not make sense to rely only
on that channel.
This fix makes this function pick a channel with the standard
helper function cifs_pick_channel.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5c86919455 upstream.
The following UAF was triggered when running fstests generic/072 with
KASAN enabled against Windows Server 2022 and mount options
'multichannel,max_channels=2,vers=3.1.1,mfsymlinks,noperm'
BUG: KASAN: slab-use-after-free in smb2_query_info_compound+0x423/0x6d0 [cifs]
Read of size 8 at addr ffff888014941048 by task xfs_io/27534
CPU: 0 PID: 27534 Comm: xfs_io Not tainted 6.6.0-rc7 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
Call Trace:
dump_stack_lvl+0x4a/0x80
print_report+0xcf/0x650
? srso_alias_return_thunk+0x5/0x7f
? srso_alias_return_thunk+0x5/0x7f
? __phys_addr+0x46/0x90
kasan_report+0xda/0x110
? smb2_query_info_compound+0x423/0x6d0 [cifs]
? smb2_query_info_compound+0x423/0x6d0 [cifs]
smb2_query_info_compound+0x423/0x6d0 [cifs]
? __pfx_smb2_query_info_compound+0x10/0x10 [cifs]
? srso_alias_return_thunk+0x5/0x7f
? __stack_depot_save+0x39/0x480
? kasan_save_stack+0x33/0x60
? kasan_set_track+0x25/0x30
? ____kasan_slab_free+0x126/0x170
smb2_queryfs+0xc2/0x2c0 [cifs]
? __pfx_smb2_queryfs+0x10/0x10 [cifs]
? __pfx___lock_acquire+0x10/0x10
smb311_queryfs+0x210/0x220 [cifs]
? __pfx_smb311_queryfs+0x10/0x10 [cifs]
? srso_alias_return_thunk+0x5/0x7f
? __lock_acquire+0x480/0x26c0
? lock_release+0x1ed/0x640
? srso_alias_return_thunk+0x5/0x7f
? do_raw_spin_unlock+0x9b/0x100
cifs_statfs+0x18c/0x4b0 [cifs]
statfs_by_dentry+0x9b/0xf0
fd_statfs+0x4e/0xb0
__do_sys_fstatfs+0x7f/0xe0
? __pfx___do_sys_fstatfs+0x10/0x10
? srso_alias_return_thunk+0x5/0x7f
? lockdep_hardirqs_on_prepare+0x136/0x200
? srso_alias_return_thunk+0x5/0x7f
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Allocated by task 27534:
kasan_save_stack+0x33/0x60
kasan_set_track+0x25/0x30
__kasan_kmalloc+0x8f/0xa0
open_cached_dir+0x71b/0x1240 [cifs]
smb2_query_info_compound+0x5c3/0x6d0 [cifs]
smb2_queryfs+0xc2/0x2c0 [cifs]
smb311_queryfs+0x210/0x220 [cifs]
cifs_statfs+0x18c/0x4b0 [cifs]
statfs_by_dentry+0x9b/0xf0
fd_statfs+0x4e/0xb0
__do_sys_fstatfs+0x7f/0xe0
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Freed by task 27534:
kasan_save_stack+0x33/0x60
kasan_set_track+0x25/0x30
kasan_save_free_info+0x2b/0x50
____kasan_slab_free+0x126/0x170
slab_free_freelist_hook+0xd0/0x1e0
__kmem_cache_free+0x9d/0x1b0
open_cached_dir+0xff5/0x1240 [cifs]
smb2_query_info_compound+0x5c3/0x6d0 [cifs]
smb2_queryfs+0xc2/0x2c0 [cifs]
This is a race between open_cached_dir() and cached_dir_lease_break()
where the cache entry for the open directory handle receives a lease
break while creating it. And before returning from open_cached_dir(),
we put the last reference of the new @cfid because of
!@cfid->has_lease.
Besides the UAF, while running xfstests a lot of missed lease breaks
have been noticed in tests that run several concurrent statfs(2) calls
on those cached fids
CIFS: VFS: \\w22-root1.gandalf.test No task to wake, unknown frame...
CIFS: VFS: \\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...
CIFS: VFS: \\w22-root1.gandalf.test smb buf 00000000715bfe83 len 108
CIFS: VFS: Dump pending requests:
CIFS: VFS: \\w22-root1.gandalf.test No task to wake, unknown frame...
CIFS: VFS: \\w22-root1.gandalf.test Cmd: 18 Err: 0x0 Flags: 0x1...
CIFS: VFS: \\w22-root1.gandalf.test smb buf 000000005aa7316e len 108
...
To fix both, in open_cached_dir() ensure that @cfid->has_lease is set
right before sending out compounded request so that any potential
lease break will be get processed by demultiplex thread while we're
still caching @cfid. And, if open failed for some reason, re-check
@cfid->has_lease to decide whether or not put lease reference.
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Check if @cfid->time is set in laundromat so we guarantee that only
fully cached fids will be selected for removal. While we're at it,
add missing locks to protect access of @cfid fields in order to avoid
races with open_cached_dir() and cfids_laundromat_worker(),
respectively.
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
By having laundromat kthread processing cached directories on every
second turned out to be overkill, especially when having multiple SMB
mounts.
Relax it by using a delayed worker instead that gets scheduled on
every @dir_cache_timeout (default=30) seconds per tcon.
This also fixes the 1s delay when tearing down tcon.
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
disabled
When no directory lease support, or for IPC shares where directories
can not be opened, do not start an unneeded laundromat thread for
that mount (it wastes resources).
Fixes: d14de8067e ("cifs: Add a laundromat thread for cached directories")
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Acked-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Allow adjusting the maximum number of cached directories per share
(defaults to 16) via mount parm "max_cached_dirs"
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently with directory leases we cache directory contents for a fixed period
of time (default 30 seconds) but for many workloads this is too short. Allow
configuring the maximum amount of time directory entries are cached when a
directory lease is held on that directory. Add module load parm "max_dir_cache"
For example to set the timeout to 10 minutes you would do:
echo 600 > /sys/module/cifs/parameters/dir_cache_timeout
or to disable caching directory contents:
echo 0 > /sys/module/cifs/parameters/dir_cache_timeout
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We read and cache directory contents when we get directory
lease, so we should ask for read permission to read contents
of directory.
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko
and helper modules) to new fs/smb subdirectory:
fs/cifs --> fs/smb/client
fs/ksmbd --> fs/smb/server
fs/smbfs_common --> fs/smb/common
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steve French