CVE-2026-31710 PUBLISHED

smb: client: fix dir separator in SMB1 UNIX mounts

Assigner: Linux
Reserved: 09.03.2026 Published: 01.05.2026 Updated: 01.05.2026

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix dir separator in SMB1 UNIX mounts

When calling cifs_mount_get_tcon() with SMB1 UNIX mounts, @cifs_sb->mnt_cifs_flags needs to be read or updated only after calling reset_cifs_unix_caps(), otherwise it might end up with missing CIFS_MOUNT_POSIXACL and CIFS_MOUNT_POSIX_PATHS bits.

This fixes the wrong dir separator used in paths caused by the missing CIFS_MOUNT_POSIX_PATHS bit in cifs_sb_info::mnt_cifs_flags.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 4fc3a433c13944ee5766ec5b9bf6f1eb4d29b880 to fbbfcf35e1ee3396631f3dc6214cb626aa9814c3 (excl.)
  • affected from 4fc3a433c13944ee5766ec5b9bf6f1eb4d29b880 to c4d3fc5844d685441befd0caaab648321013cdfd (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 7.0 is affected
  • unaffected from 0 to 7.0 (excl.)
  • unaffected from 7.0.2 to 7.0.* (incl.)
  • unaffected from 7.1-rc1 to * (incl.)

References