mtd: part: reject MTDPART_OFS_RETAIN in mtd_add_partition()
In the Linux kernel, the following vulnerability has been resolved: mtd: part: reject MTDPART_OFS_RETAIN in mtd_add_partition() mtd_add_partition() does not reject the special offset value MTDPART_OFS_RETAIN (-3), which leads to a WARN_ON in add_mtd_device() when called through the BLKPG ioctl on NAND devices. The RETAIN value depends on cur_offset being the end of the previous partition, but in the dynamic partition path cur_offset equals the offset argument itself, causing undefined behavior. Commit 5daa7b21496a ("mtd: prepare partition add and del functions for ioctl requests") introduced mtd_add_partition() and correctly rejected MTDPART_OFS_APPEND (-1) and MTDPART_OFS_NXTBLK (-2), since those special offsets rely on cur_offset tracking the previous partition's end. However, commit 1a31368bf92e ("mtd: add a flags for partitions which should just leave smth. after them") later added MTDPART_OFS_RETAIN (-3) for the static partition table path without updating mtd_add_partition() to also reject this value. With offset=-3 passed via BLKPG, the RETAIN size calculation in allocate_partition() underflows (parent_size - 0xFFFFFFFFFFFFFFFD = parent_size + 3). If the underflow result does not appear to leave enough space, allocate_partition() jumps to out_register via goto, skipping erasesize initialization. This results in erasesize=0, which triggers: WARN_ON((!mtd->erasesize || !master->_erase) && !(mtd->flags & MTD_NO_ERASE)) in add_mtd_device(). If the underflow result appears
CVE-2026-93048
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-2026-93048
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": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "701c3ae7273e1adc20db5d97c42e0139b479f16b",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "6aaab2ace3f7b55733d904e5549acf8405f03642",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "181c1bff940e7d3e34ca485d37e3cdbfe409203c",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "a536eb57be58442b19398b2783071007ecfb1735",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "e204e5c49a012f99638633fdbd773e3c86260053",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "398aca2f90122d5abbabff1079deaeb885fe9e40",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "c645f6dd1af2ecc70fd3578e141f2f71fa9e4eff",
"versionType": "git"
},
{
"status": "affected",
"version": "1a31368bf92ef2a7da3ba379672c405bd2751df9",
"lessThan": "b759d5bb6265419344ee9729fd0dc07ad85719d8",
"versionType": "git"
}
],
"programFiles": [
"drivers/mtd/mtdpart.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.2",
"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": "6.12.110",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/mtd/mtdpart.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-93048
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #37784 · Revision 1
- Added to Heist Feed
- Publisher date