kernel/git/stable/linux-stable.git/fs/smb/client, branch linux-6.17.y

cifs: Fix handling of a beyond-EOF DIO/unbuffered read over SMB2

2025-12-18T13:00:12+00:00

[ Upstream commit 4ae4dde6f34a4124c65468ae4fa1f915fb40f900 ] If a DIO read or an unbuffered read request extends beyond the EOF, the server will return a short read and a status code indicating that EOF was hit, which gets translated to -ENODATA. Note that the client does not cap the request at i_size, but asks for the amount requested in case there's a race on the server with a third party. Now, on the client side, the request will get split into multiple subrequests if rsize is smaller than the full request size. A subrequest that starts before or at the EOF and returns short data up to the EOF will be correctly handled, with the NETFS_SREQ_HIT_EOF flag being set, indicating to netfslib that we can't read more. If a subrequest, however, starts after the EOF and not at it, HIT_EOF will not be flagged, its error will be set to -ENODATA and it will be abandoned. This will cause the request as a whole to fail with -ENODATA. Fix this by setting NETFS_SREQ_HIT_EOF on any subrequest that lies beyond the EOF marker. Fixes: 1da29f2c39b6 ("netfs, cifs: Fix handling of short DIO read") Signed-off-by: David Howells Reviewed-by: Paulo Alcantara (Red Hat) cc: Shyam Prasad N cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French Signed-off-by: Sasha Levin

cifs: Fix handling of a beyond-EOF DIO/unbuffered read over SMB1

2025-12-18T13:00:12+00:00

[ Upstream commit 9d85ac939d52e93d80efb01a299c6f0bedb30487 ] If a DIO read or an unbuffered read request extends beyond the EOF, the server will return a short read and a status code indicating that EOF was hit, which gets translated to -ENODATA. Note that the client does not cap the request at i_size, but asks for the amount requested in case there's a race on the server with a third party. Now, on the client side, the request will get split into multiple subrequests if rsize is smaller than the full request size. A subrequest that starts before or at the EOF and returns short data up to the EOF will be correctly handled, with the NETFS_SREQ_HIT_EOF flag being set, indicating to netfslib that we can't read more. If a subrequest, however, starts after the EOF and not at it, HIT_EOF will not be flagged, its error will be set to -ENODATA and it will be abandoned. This will cause the request as a whole to fail with -ENODATA. Fix this by setting NETFS_SREQ_HIT_EOF on any subrequest that lies beyond the EOF marker. This can be reproduced by mounting with "cache=none,sign,vers=1.0" and doing a read of a file that's significantly bigger than the size of the file (e.g. attempting to read 64KiB from a 16KiB file). Fixes: a68c74865f51 ("cifs: Fix SMB1 readv/writev callback in the same way as SMB2/3") Signed-off-by: David Howells Reviewed-by: Paulo Alcantara (Red Hat) cc: Shyam Prasad N cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: fix invalid username check in smb3_fs_context_parse_param()

2025-12-12T17:40:20+00:00

[ Upstream commit ed6612165b74f09db00ef0abaf9831895ab28b7f ] Since the maximum return value of strnlen(..., CIFS_MAX_USERNAME_LEN) is CIFS_MAX_USERNAME_LEN, length check in smb3_fs_context_parse_param() is always FALSE and invalid. Fix the comparison in if statement. Signed-off-by: Yiqi Sun Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: client: fix memory leak in cifs_construct_tcon()

2025-12-06T21:27:36+00:00

commit 3184b6a5a24ec9ee74087b2a550476f386df7dc2 upstream. When having a multiuser mount with domain= specified and using cifscreds, cifs_set_cifscreds() will end up setting @ctx->domainname, so it needs to be freed before leaving cifs_construct_tcon(). This fixes the following memory leak reported by kmemleak: mount.cifs //srv/share /mnt -o domain=ZELDA,multiuser,... su - testuser cifscreds add -d ZELDA -u testuser ... ls /mnt/1 ... umount /mnt echo scan > /sys/kernel/debug/kmemleak cat /sys/kernel/debug/kmemleak unreferenced object 0xffff8881203c3f08 (size 8): comm "ls", pid 5060, jiffies 4307222943 hex dump (first 8 bytes): 5a 45 4c 44 41 00 cc cc ZELDA... backtrace (crc d109a8cf): __kmalloc_node_track_caller_noprof+0x572/0x710 kstrdup+0x3a/0x70 cifs_sb_tlink+0x1209/0x1770 [cifs] cifs_get_fattr+0xe1/0xf50 [cifs] cifs_get_inode_info+0xb5/0x240 [cifs] cifs_revalidate_dentry_attr+0x2d1/0x470 [cifs] cifs_getattr+0x28e/0x450 [cifs] vfs_getattr_nosec+0x126/0x180 vfs_statx+0xf6/0x220 do_statx+0xab/0x110 __x64_sys_statx+0xd5/0x130 do_syscall_64+0xbb/0x380 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: f2aee329a68f ("cifs: set domainName when a domain-key is used in multiuser") Signed-off-by: Paulo Alcantara (Red Hat) Reviewed-by: David Howells Cc: Jay Shin Cc: stable@vger.kernel.org Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

smb: client: fix incomplete backport in cfids_invalidation_worker()

2025-12-01T10:46:06+00:00

The previous commit bdb596ceb4b7 ("smb: client: fix potential UAF in smb2_close_cached_fid()") was an incomplete backport and missed one kref_put() call in cfids_invalidation_worker() that should have been converted to close_cached_dir(). Fixes: bdb596ceb4b7 ("smb: client: fix potential UAF in smb2_close_cached_fid()")" Signed-off-by: Henrique Carvalho Signed-off-by: Greg Kroah-Hartman

smb: client: handle lack of IPC in dfs_cache_refresh()

2025-12-01T10:46:03+00:00

[ Upstream commit fac56c4651ae95f3f2b468c2cf1884cf0e6d18c1 ] In very rare cases, DFS mounts could end up with SMB sessions without any IPC connections. These mounts are only possible when having unexpired cached DFS referrals, hence not requiring any IPC connections during the mount process. Try to establish those missing IPC connections when refreshing DFS referrals. If the server is still rejecting it, then simply ignore and leave expired cached DFS referral for any potential DFS failovers. Reported-by: Jay Shin Signed-off-by: Paulo Alcantara (Red Hat) Cc: David Howells Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French Signed-off-by: Sasha Levin

cifs: fix typo in enable_gcm_256 module parameter

2025-12-01T10:46:02+00:00

[ Upstream commit f765fdfcd8b5bce92c6aa1a517ff549529ddf590 ] Fix typo in description of enable_gcm_256 module parameter Suggested-by: Thomas Spear Signed-off-by: Steve French Signed-off-by: Sasha Levin

cifs: fix memory leak in smb3_fs_context_parse_param error path

2025-12-01T10:45:59+00:00

[ Upstream commit 7e4d9120cfa413dd34f4f434befc5dbe6c38b2e5 ] Add proper cleanup of ctx->source and fc->source to the cifs_parse_mount_err error handler. This ensures that memory allocated for the source strings is correctly freed on all error paths, matching the cleanup already performed in the success path by smb3_cleanup_fs_context_contents(). Pointers are also set to NULL after freeing to prevent potential double-free issues. This change fixes a memory leak originally detected by syzbot. The leak occurred when processing Opt_source mount options if an error happened after ctx->source and fc->source were successfully allocated but before the function completed. The specific leak sequence was: 1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory 2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory 3. A subsequent error jumps to cifs_parse_mount_err 4. The old error handler freed passwords but not the source strings, causing the memory to leak. This issue was not addressed by commit e8c73eb7db0a ("cifs: client: fix memory leak in smb3_fs_context_parse_param"), which only fixed leaks from repeated fsconfig() calls but not this error path. Patch updated with minor change suggested by kernel test robot Reported-by: syzbot+87be6809ed9bf6d718e3@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=87be6809ed9bf6d718e3 Fixes: 24e0a1eff9e2 ("cifs: switch to new mount api") Reviewed-by: David Howells Signed-off-by: Shaurya Rane Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: client: introduce close_cached_dir_locked()

2025-12-01T10:45:38+00:00

commit a9d1f38df7ecd0e21233447c9cc6fa1799eddaf3 upstream. Replace close_cached_dir() calls under cfid_list_lock with a new close_cached_dir_locked() variant that uses kref_put() instead of kref_put_lock() to avoid recursive locking when dropping references. While the existing code works if the refcount >= 2 invariant holds, this area has proven error-prone. Make deadlocks impossible and WARN on invariant violations. Cc: stable@vger.kernel.org Reviewed-by: David Howells Signed-off-by: Henrique Carvalho Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

smb: client: fix cifs_pick_channel when channel needs reconnect

2025-11-24T09:37:46+00:00

commit 79280191c2fd7f24899bbd640003b5389d3c109c upstream. cifs_pick_channel iterates candidate channels using cur. The reconnect-state test mistakenly used a different variable. This checked the wrong slot and would cause us to skip a healthy channel and to dispatch on one that needs reconnect, occasionally failing operations when a channel was down. Fix by replacing for the correct variable. Fixes: fc43a8ac396d ("cifs: cifs_pick_channel should try selecting active channels") Cc: stable@vger.kernel.org Reviewed-by: Shyam Prasad N Signed-off-by: Henrique Carvalho Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman