CVE-2026-98170 PUBLISHED

smb: client: fix OOB struct field reads in move_smb2_ea_to_cifs()

Assigner: Linux
Reserved: 25.09.2026 Published: 06.10.2026 Updated: 06.10.2026

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

smb: client: fix OOB struct field reads in move_smb2_ea_to_cifs()

In move_smb2_ea_to_cifs(), the while (src_size > 0) loop condition is insufficient. It allows iteration to continue even if the remaining src_size is too small to contain a complete smb2_ea_info structure. Consequently, reads of ea_name_length and ea_value_length can occur out-of-bounds.

Fix this by ensuring src_size >= sizeof(src) before attempting to read any structure fields. Additionally, reject any next_entry_offset that is smaller than sizeof(src) or that would advance the pointer beyond the available buffer.

Note that for calls where the server returns a malformed EA list, the error returned to userspace changes from -ENODATA (getxattr) or -ERANGE (listxattr) to -EIO. This correctly signals a server protocol error rather than misleadingly indicating "attribute not present" or "output buffer too small".

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 95907fea4fd8ccc736e0a428e52159b4d42b9958 to d3546cecbf81d98bf3b472d341f981eb48c04f47 (excl.)
  • affected from 95907fea4fd8ccc736e0a428e52159b4d42b9958 to 34a3942e787b9c59758115bd65fe1ec89d68c7a4 (excl.)
  • affected from 95907fea4fd8ccc736e0a428e52159b4d42b9958 to 13efcd37a9b3d6ffa1579c3dda3e29c893ed9bca (excl.)
  • affected from 95907fea4fd8ccc736e0a428e52159b4d42b9958 to eeb5ef6083e1cefa2ef75041b5597ff228b8d7bb (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.14 is affected
  • unaffected from 0 to 4.14 (excl.)
  • unaffected from 6.12.112 to 6.12.* (incl.)
  • unaffected from 6.18.54 to 6.18.* (incl.)
  • unaffected from 7.2.8 to 7.2.* (incl.)
  • unaffected from 7.3-rc4 to * (incl.)

References