exit: prevent preemption of oopsing TASK_DEAD task
In the Linux kernel, the following vulnerability has been resolved: exit: prevent preemption of oopsing TASK_DEAD task When an already-exiting task oopses, make_task_dead() currently calls do_task_dead() with preemption enabled. That is forbidden: do_task_dead() calls __schedule(), which has a comment saying "WARNING: must be called with preemption disabled!". If an oopsing task is preempted in do_task_dead(), between becoming TASK_DEAD and entering the scheduler explicitly, bad things happen: finish_task_switch() assumes that once the scheduler has switched away from a TASK_DEAD task, the task can never run again and its stack is no longer needed; but that assumption apparently doesn't hold if the dead task was preempted (the SM_PREEMPT case). This means that the scheduler ends up repeatedly dropping references on the dead task's stack, which can lead to use-after-free or double-free of the entire task stack; in other words, two tasks can end up running on the same stack, resulting in various kinds of memory corruption. (This does not just affect "recursively oopsing" tasks; it is enough to oops once during task exit, for example in a file_operations::release handler)
CVE-2026-46173
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-2026-46173
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": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "3d6fb8a7690c23e3213c4b008f64d89a44b98737",
"versionType": "git"
},
{
"status": "affected",
"version": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "640b4c00fb0e2920327435f6176cbefc3c546165",
"versionType": "git"
},
{
"status": "affected",
"version": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "7b2800ba5f5f77a8ee7f4cbadb19cf1264597a34",
"versionType": "git"
},
{
"status": "affected",
"version": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "6f49f94f3b11fe8bff1bf2a054143789e76aaf17",
"versionType": "git"
},
{
"status": "affected",
"version": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "9756b3db5db6c2f5eccb32dddbd88eb4c54f575e",
"versionType": "git"
},
{
"status": "affected",
"version": "7f80a2fd7db9a55894fd841915236aca611291b5",
"lessThan": "c1fa0bb633e4a6b11e83ffc57fa5abe8ebb87891",
"versionType": "git"
}
],
"programFiles": [
"kernel/exit.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.175",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.140",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.88",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.30",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.7",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/exit.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-46173
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40148 · Revision 1
- Added to Heist Feed
- Publisher date