smb: client: fix unaligned access in WSL reparse point parser

Browse source

When wsl_to_fattr() parses WSL extended attributes, it computes a
payload pointer from ea->ea_data + ea_name_length + 1.  Since the
smb2_file_full_ea_info struct is __packed and all WSL xattr names are
6 bytes long, the value pointer always lands at an odd byte offset,
never satisfying __le32 or __le64 alignment requirements.

The code then casts this pointer to __le32 * or __le64 * and
dereferences it directly, which may cause alignment faults on some
architectures.

Replace all such casts with get_unaligned_le32() and
get_unaligned_le64() in reparse_mkdev(), wsl_make_kuid(),
wsl_make_kgid() and wsl_to_fattr().

Closes: https://sashiko.dev/#/patchset/20260906200517.725015-1-pc%40manguebit.org
Fixes: 78e26bec4d ("smb: client: parse uid, gid, mode and dev from WSL reparse points")
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: stable@vger.kernel.org

...

This commit is contained in:

Paulo Alcantara 2026-09-13 21:09:15 -03:00

parent e75c96157d

commit e1aeaf79de

2 changed files with 6 additions and 5 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

4

fs/smb/client/reparse.c

View file

7

fs/smb/client/reparse.h

View file