CVE-2026-89557
CVE CVE-2026-89557EUVD EUVD-2026-76468Published 2026-09-11T19:44:29.000ZLast changed 2026-09-14T12:00:58.000ZCVSS 7.8
What the advisory describes
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.
Source: EUVD (ENISA), in the words of the advisory.
Products the advisory names
These come from the advisory itself, not from any check we performed.
- Linux — Linux patch: 5.15.221; patch: 6.6.157; 2699b67223aca6b1450fc2f72e40fada952afc85 <573fb68105fdc6a127ba6069e58a0d2aff3c9f93; patch: 6.18.50; patch: 0; patch: 6.1.188; 2699b67223aca6b1450fc2f72e40fada952afc85 <94c820d99a4305d4ded41a97ed37ec7d26c56e7f; patch: 7.3-rc1; 3.1; 2699b67223aca6b1450fc2f72e40fada952afc85 <323f3a056dbccb39a642ebde642044a680f3a6d6; 2699b67223aca6b1450fc2f72e40fada952afc85 <3b097416b4cff77285c1f472fc2c4058d8a7554f; 2699b67223aca6b1450fc2f72e40fada952afc85 <35d522bd32462afcf1981dab6da8a9256c26c1e0; patch: 5.10.270; patch: 6.12.109; 2699b67223aca6b1450fc2f72e40fada952afc85 <df7d4d011d5ace20699ea948712f09f9ac08924f; patch: 7.2.4; 2699b67223aca6b1450fc2f72e40fada952afc85 <0a03f9541c06fda64301dcf94f376f07ce2cc396; 2699b67223aca6b1450fc2f72e40fada952afc85 <75d15738fd33a782606d0dc80cfeff47edf2ddd8
The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.
Carried in the product catalogue
An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.
- Linux — Linux
Does this concern one of your customers?
This page cannot answer that — it does not know your estate. Whoever has recorded their environments gets the answer the morning after publication, together with a paragraph they can forward to the customer unedited.
Try it for 28 daysPatchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.