From cf4d35896621b7298eef51b7a465e5c0cb22f670 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Sun, 6 Sep 2026 14:39:44 -0300 Subject: [PATCH] smb: client: fix uid/gid override in getattr with posix extensions When mounting with 'multiuser,posix' options, cifs_getattr() overrides the server-provided uid/gid with the current process's fsuid/fsgid. This is because the condition only checks for unix extensions (tcon->unix_ext) but not posix extensions (tcon->posix_extensions). With SMB3 POSIX extensions, the server provides real uid/gid values just like with unix extensions, so they should be preserved rather than replaced with the caller's credentials. Add a tcon->posix_extensions check to the condition so that uid/gid from the server are properly reported in stat results. Reported-by: Arthur Lesuisse Closes: https://lore.kernel.org/r/DB9P190MB2012266F6B8DECBE5D26A1798DB52@DB9P190MB2012.EURP190.PROD.OUTLOOK.COM Suggested-by: Arthur Lesuisse Reviewed-by: Namjae Jeon Signed-off-by: Paulo Alcantara Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- fs/smb/client/inode.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c index 12ed8db10e00..49f9993ad567 100644 --- a/fs/smb/client/inode.c +++ b/fs/smb/client/inode.c @@ -2992,14 +2992,14 @@ int cifs_getattr(struct mnt_idmap *idmap, const struct path *path, stat->attributes |= STATX_ATTR_ENCRYPTED; /* - * If on a multiuser mount without unix extensions or cifsacl being - * enabled, and the admin hasn't overridden them, set the ownership - * to the fsuid/fsgid of the current process. + * If on a multiuser mount without unix extensions, posix extensions + * or cifsacl being enabled, and the admin hasn't overridden them, + * set the ownership to the fsuid/fsgid of the current process. */ sbflags = cifs_sb_flags(cifs_sb); if ((sbflags & CIFS_MOUNT_MULTIUSER) && !(sbflags & CIFS_MOUNT_CIFS_ACL) && - !tcon->unix_ext) { + !tcon->unix_ext && !tcon->posix_extensions) { if (!(sbflags & CIFS_MOUNT_OVERR_UID)) stat->uid = current_fsuid(); if (!(sbflags & CIFS_MOUNT_OVERR_GID))