md: do overflow check for sb->bblog_shift in super_1_load()
Summary
| CVE | CVE-2026-89557 |
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| State | PUBLISHED |
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| Assigner | Linux |
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| Source Priority | CVE Program / NVD first with legacy fallback |
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| Published | 2026-09-11 20:19:39 UTC |
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| Updated | 2026-09-11 20:19:39 UTC |
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| Description | In the Linux kernel, the following vulnerability has been resolved:
md: do overflow check for sb->bblog_shift in super_1_load()
In super_1_load(), sb->bblog_shift is an __u8 type value loaded from on-
disk superblock. It is used for badblocks API badblocks_set() by the
following sequence,
1930 rdev->badblocks.shift = sb->bblog_shift;
1931 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) {
1932 u64 bb = le64_to_cpu(*bbp);
1933 int count = bb & (0x3ff);
1934 u64 sector = bb >> 10;
1935 sector <<= sb->bblog_shift;
1936 count <<= sb->bblog_shift;
1937 if (bb + 1 == 0)
1938 break;
1939 if (!badblocks_set(&rdev->badblocks, sector, count, 1))
1940 return -EINVAL;
1941 }
bb->bblog_shit is in range of 0-255, variable sector is 64bit width, for
an invalid bb->bblog_shit, it is possible to make sector be overflowed
by the following calculation,
1935 sector <<= sb->bblog_shift;
Then in turn when call badblocks_set() at line 1939 with the invalid
rdev->badblocks.shift set at line 1930, may result an overflow inside
_badblocks_clear() in block/badblocks.c.
Although there are many places to call badblocks APIs, the non-zero
shift value is only used in super_1_load(), other places always use 0 as
the shift value. Therefore it is unnecessary to do a general shift value
overflow check inside badblock API, and just check here as the caller.
This may avoid unnecessary check, make the badblocks API code more simple
and elegant. |
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Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 2699b67223aca6b1450fc2f72e40fada952afc85 75d15738fd33a782606d0dc80cfeff47edf2ddd8 git |
Not specified |
| CNA |
Linux |
Linux |
affected 2699b67223aca6b1450fc2f72e40fada952afc85 3b097416b4cff77285c1f472fc2c4058d8a7554f git |
Not specified |
| CNA |
Linux |
Linux |
affected 2699b67223aca6b1450fc2f72e40fada952afc85 df7d4d011d5ace20699ea948712f09f9ac08924f git |
Not specified |
| CNA |
Linux |
Linux |
affected 2699b67223aca6b1450fc2f72e40fada952afc85 35d522bd32462afcf1981dab6da8a9256c26c1e0 git |
Not specified |
| CNA |
Linux |
Linux |
affected 3.1 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 3.1 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.109 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.50 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.2.4 7.2.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.3-rc1 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/3b097416b4cff77285c1f472fc2c4058d8a7554f |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/35d522bd32462afcf1981dab6da8a9256c26c1e0 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/df7d4d011d5ace20699ea948712f09f9ac08924f |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/75d15738fd33a782606d0dc80cfeff47edf2ddd8 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.