CVE-2026-31478: ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len() After this commit (e2b76ab8b5c9 "ksmbd: add support for read compound"), response buffer management was changed to use dynamic iov array. In the new design, smb2_calc_max_out_buf_len() expects the second argument (hdr2_len) to be the offset of ->Buffer field in the response structure, not a hardcoded magic number. Fix the remaining call sites to use the correct offsetof() value.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

f2283680a80571ca82d710bc6ecd8f8beac67d63 to < 70b4c414889492c522b6e4331562360f49be2361affected
9f297df20d93411c0b4ddad7f88ba04a7cd36e77 to < 9a7166f0ef8cbb7bb48dd05e2471d995566003f5affected
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d to < c3a89e3ec1ccf64fa6a34e391e1581ebbcba8683affected
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d to < 6aef1765d6807e0f027cd87f6ac973eb0879a46daffected
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d to < 80824c7e527b70cf9039534e60aff592e8f209d1affected
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d to < 4cb537ae4f37d7d0f617815ed4bed7173fb50861affected
e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d to < 0e55f63dd08f09651d39e1b709a91705a8a0ddcbaffected
5.15.145 to < 5.15.203affected
6.1.71 to < 6.1.168affected

Linux Linux

Default version status: affected

6.6affected
0 to < 6.6unaffected
5.15.203 to ≤ 5.15.*unaffected
6.1.168 to ≤ 6.1.*unaffected
6.6.131 to ≤ 6.6.*unaffected
6.12.80 to ≤ 6.12.*unaffected
6.18.21 to ≤ 6.18.*unaffected
6.19.11 to ≤ 6.19.*unaffected
7.0 to ≤ *unaffected

CVE-2026-31478

ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()

Description

Affected products

Linux Linux

Linux Linux

References