CVE-2026-99103
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: workqueue: Fix unbound pool lifetime for pending pwqs KASAN reports a use-after-free of an unbound worker_pool in node_activate_pending_pwq(): BUG: KASAN: slab-use-after-free in _raw_spin_trylock+0x6d/0x120 Read of size 4 at addr ffff8880089ce000 by task kworker/u22:0/318 CPU: 1 UID: 0 PID: 318 Comm: kworker/u22:0 Not tainted 7.2.0 #1 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: 0x0 (flush-8:0) Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xce/0x610 kasan_report+0xce/0x100 _raw_spin_trylock+0x6d/0x120 pwq_dec_nr_in_flight+0x4b4/0xcb0 process_one_work+0x921/0x11a0 worker_thread+0x4d0/0xd20 kthread+0x2de/0x3c0 ret_from_fork+0x3aa/0x620 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 311: alloc_pwq+0x439/0xca0 apply_wqattrs_prepare+0x75e/0xd10 apply_workqueue_attrs_locked+0x44/0xa0 wq_nice_store+0x350/0x450 Freed by task 0: kfree+0x127/0x3b0 rcu_core+0x523/0x1780 handle_softirqs+0x1b3/0x610 Last potentially related work creation: put_unbound_pool+0x3f3/0x7d0 pwq_release_workfn+0x494/0x8e0 kthread_worker_fn+0x1ff/0x790 Canceling the last inactive work skips pwq_dec_nr_active(), so an empty pwq can remain on pending_pwqs when its refcnt reaches zero. pwq_release_workfn() currently puts the pool before removing that pwq. If this drops the last pool reference, the pool can be RCU-freed while the pwq remains reachable, and node_activate_pending_pwq() may trylock the freed pool->lock. Remove the pwq from pending_pwqs before putting the pool.
View original CVE JSON
{
"id": "CVE-2026-99103",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-10-28T11:17:29.593",
"lastModified": "2026-10-30T13:21:45.183",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nworkqueue: Fix unbound pool lifetime for pending pwqs\n\nKASAN reports a use-after-free of an unbound worker_pool in\nnode_activate_pending_pwq():\n\n BUG: KASAN: slab-use-after-free in _raw_spin_trylock+0x6d/0x120\n Read of size 4 at addr ffff8880089ce000 by task kworker/u22:0/318\n\n CPU: 1 UID: 0 PID: 318 Comm: kworker/u22:0 Not tainted 7.2.0 #1 PREEMPT(lazy)\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014\n Workqueue: 0x0 (flush-8:0)\n Call Trace:\n <TASK>\n dump_stack_lvl+0x53/0x70\n print_report+0xce/0x610\n kasan_report+0xce/0x100\n _raw_spin_trylock+0x6d/0x120\n pwq_dec_nr_in_flight+0x4b4/0xcb0\n process_one_work+0x921/0x11a0\n worker_thread+0x4d0/0xd20\n kthread+0x2de/0x3c0\n ret_from_fork+0x3aa/0x620\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\n Allocated by task 311:\n alloc_pwq+0x439/0xca0\n apply_wqattrs_prepare+0x75e/0xd10\n apply_workqueue_attrs_locked+0x44/0xa0\n wq_nice_store+0x350/0x450\n\n Freed by task 0:\n kfree+0x127/0x3b0\n rcu_core+0x523/0x1780\n handle_softirqs+0x1b3/0x610\n\n Last potentially related work creation:\n put_unbound_pool+0x3f3/0x7d0\n pwq_release_workfn+0x494/0x8e0\n kthread_worker_fn+0x1ff/0x790\n\nCanceling the last inactive work skips pwq_dec_nr_active(), so an empty\npwq can remain on pending_pwqs when its refcnt reaches zero.\npwq_release_workfn() currently puts the pool before removing that pwq.\nIf this drops the last pool reference, the pool can be RCU-freed while\nthe pwq remains reachable, and node_activate_pending_pwq() may trylock\nthe freed pool->lock.\n\nRemove the pwq from pending_pwqs before putting the pool."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/workqueue.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "5a70baec2294e8a7d0fcc4558741c23e752dad5c",
"lessThan": "6741dd3fd38e47c08bc39d11ef5fa141fa6d0441",
"versionType": "git",
"status": "affected"
},
{
"version": "843288afd3cc6f3342659c6cf81fc47684d25563",
"lessThan": "9f5d5aef3072a33c6f9bfb954bb0cba1c2541849",
"versionType": "git",
"status": "affected"
},
{
"version": "5797b1c18919cd9c289ded7954383e499f729ce0",
"lessThan": "390b9542fe670b8936738140ef9f349df6adeab6",
"versionType": "git",
"status": "affected"
},
{
"version": "5797b1c18919cd9c289ded7954383e499f729ce0",
"lessThan": "f320b85c90fe5fc9d4d06badd450518323a94a7f",
"versionType": "git",
"status": "affected"
},
{
"version": "5797b1c18919cd9c289ded7954383e499f729ce0",
"lessThan": "3d2ef2b9f4c084ab498494d26495a82f7e15407b",
"versionType": "git",
"status": "affected"
},
{
"version": "5797b1c18919cd9c289ded7954383e499f729ce0",
"lessThan": "cf9c8aaea0d47410df8708bec195889f3a85cd3c",
"versionType": "git",
"status": "affected"
},
{
"version": "fc67aebe34f22632ccb22faea48cc4d3134620a2",
"versionType": "git",
"status": "affected"
},
{
"version": "6.6.23",
"lessThan": "6.6.25",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.8.2",
"lessThan": "6.8.4",
"versionType": "semver",
"status": "affected"
},
{
"version": "6.7.11",
"lessThan": "6.8",
"versionType": "semver",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/workqueue.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.9",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.9",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.6.25",
"lessThanOrEqual": "6.6.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.8.4",
"lessThanOrEqual": "6.8.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.115",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.59",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.13",
"lessThanOrEqual": "7.2.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.3",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {},
"references": [
{
"url": "https://git.kernel.org/stable/c/390b9542fe670b8936738140ef9f349df6adeab6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/3d2ef2b9f4c084ab498494d26495a82f7e15407b",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/6741dd3fd38e47c08bc39d11ef5fa141fa6d0441",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/9f5d5aef3072a33c6f9bfb954bb0cba1c2541849",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/cf9c8aaea0d47410df8708bec195889f3a85cd3c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/f320b85c90fe5fc9d4d06badd450518323a94a7f",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}