md: do overflow check for sb->bblog_shift in super_1_load()
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.
CVE-2026-89557
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-89557
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "94c820d99a4305d4ded41a97ed37ec7d26c56e7f",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "573fb68105fdc6a127ba6069e58a0d2aff3c9f93",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "323f3a056dbccb39a642ebde642044a680f3a6d6",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "0a03f9541c06fda64301dcf94f376f07ce2cc396",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "75d15738fd33a782606d0dc80cfeff47edf2ddd8",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "3b097416b4cff77285c1f472fc2c4058d8a7554f",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "df7d4d011d5ace20699ea948712f09f9ac08924f",
"versionType": "git"
},
{
"status": "affected",
"version": "2699b67223aca6b1450fc2f72e40fada952afc85",
"lessThan": "35d522bd32462afcf1981dab6da8a9256c26c1e0",
"versionType": "git"
}
],
"programFiles": [
"drivers/md/md.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/md/md.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-89557
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #35072 · Revision 1
- Added to Heist Feed
- Publisher date