Description
In the Linux kernel, the following vulnerability has been resolved: ocfs2/dlm: validate qr_numregions in dlm_match_regions() Patch series "ocfs2/dlm: fix two bugs in dlm_match_regions()". In dlm_match_regions(), the qr_numregions field from a DLM_QUERY_REGION network message is used to drive loops over the qr_regions buffer without sufficient validation. This series fixes two issues: - Patch 1 adds a bounds check to reject messages where qr_numregions exceeds O2NM_MAX_REGIONS. The o2net layer only validates message byte length; it does not constrain field values, so a crafted message can set qr_numregions up to 255 and trigger out-of-bounds reads past the 1024-byte qr_regions buffer. - Patch 2 fixes an off-by-one in the local-vs-remote comparison loop, which uses '<=' instead of '<', reading one entry past the valid range even when qr_numregions is within bounds. This patch (of 2): The qr_numregions field from a DLM_QUERY_REGION network message is used directly as loop bounds in dlm_match_regions() without checking against O2NM_MAX_REGIONS. Since qr_regions is sized for at most O2NM_MAX_REGIONS (32) entries, a crafted message with qr_numregions > 32 causes out-of-bounds reads past the qr_regions buffer. Add a bounds check for qr_numregions before entering the loops.
CVSS breakdown
Affected products
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – d3d5efade0c79dac1cac98c0cb1115432f804439
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – f69551139caf6d24242a0ad049ee46b264e3aee0
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – 1f8b91275912cd428289c1fb424bebd7ff5302bd
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – f37de46149db49abd2b24f4f0c5a88cf4dfb5f47
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – 6c6e8fc3c007319981647b410c29bb5775048551
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – 3f474c33ebc2e2ca3fcb587d7de4375348f13373
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – 3c2d0de23ae4be22b6c18e8f0915be74d3b5fb21
- Linux / Linuxea2034416b54700e30371f2ad6517cbb94674083 – 7ab3fbb01bc6d79091bc375e5235d360cd9b78be
- Linux / Linux2.6.37 – 2.6.37
- Linux / Linux0 – 2.6.37
- Linux / Linux5.10.258 – 5.10.*
- Linux / Linux5.15.209 – 5.15.*
- Linux / Linux6.1.175 – 6.1.*
- Linux / Linux6.6.141 – 6.6.*
- Linux / Linux6.12.91 – 6.12.*
- Linux / Linux6.18.33 – 6.18.*
- Linux / Linux7.0.10 – 7.0.*
- Linux / Linux7.1 – *
References
- MISChttps://git.kernel.org/stable/c/d3d5efade0c79dac1cac98c0cb1115432f804439
- MISChttps://git.kernel.org/stable/c/f69551139caf6d24242a0ad049ee46b264e3aee0
- MISChttps://git.kernel.org/stable/c/1f8b91275912cd428289c1fb424bebd7ff5302bd
- MISChttps://git.kernel.org/stable/c/f37de46149db49abd2b24f4f0c5a88cf4dfb5f47
- MISChttps://git.kernel.org/stable/c/6c6e8fc3c007319981647b410c29bb5775048551
- MISChttps://git.kernel.org/stable/c/3f474c33ebc2e2ca3fcb587d7de4375348f13373
- MISChttps://git.kernel.org/stable/c/3c2d0de23ae4be22b6c18e8f0915be74d3b5fb21
- MISChttps://git.kernel.org/stable/c/7ab3fbb01bc6d79091bc375e5235d360cd9b78be