CVE-2026-98552
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix a refcount leak in attach_perf_ctx_data() The attach_perf_ctx_data() can race on global and !global cases. The global case is protected by global_ctx_data_rwsem and shares a single reference count using perf_ctx_data.global field. But when it races with !global case, it may miss to set the global field and result in a reference count leak. CPU1 CPU2 ---------------------------------------------------------------- attach_task_ctx_data(.global=1) attach_task_ctx_data(.global=0) cd1 = alloc_perf_ctx_data(); cd2 = alloc_perf_ctx_data(); // { .global = 0, .refcount = 1 }; try_cmpxchg(); // success, // task->perf_ctx_data = cd2 try_cmpxhg(); // fail; old = cd2 refcount_inc_not_zero(&old->refcount); // success // old.refcount = 2 free_perf_ctx_data(cd1); Then later detach_global_ctx_data() will see the data but it's not marked as global, so it won't call detach_task_ctx_data().
View original CVE JSON
{
"id": "CVE-2026-98552",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-10-18T16:17:07.267",
"lastModified": "2026-10-19T10:19:11.487",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf/core: Fix a refcount leak in attach_perf_ctx_data()\n\nThe attach_perf_ctx_data() can race on global and !global cases. The\nglobal case is protected by global_ctx_data_rwsem and shares a single\nreference count using perf_ctx_data.global field.\n\nBut when it races with !global case, it may miss to set the global field\nand result in a reference count leak.\n\n CPU1 CPU2\n ----------------------------------------------------------------\n attach_task_ctx_data(.global=1) attach_task_ctx_data(.global=0)\n cd1 = alloc_perf_ctx_data(); cd2 = alloc_perf_ctx_data();\n // { .global = 0, .refcount = 1 };\n\n try_cmpxchg(); // success,\n // task->perf_ctx_data = cd2\n try_cmpxhg(); // fail; old = cd2\n refcount_inc_not_zero(&old->refcount); // success\n // old.refcount = 2\n free_perf_ctx_data(cd1);\n\nThen later detach_global_ctx_data() will see the data but it's not\nmarked as global, so it won't call detach_task_ctx_data()."
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "506e64e710ff9573fd2b86686528762b7901b5e4",
"lessThan": "23250517cd475367653f1e99396967f54c6f1b7c",
"versionType": "git",
"status": "affected"
},
{
"version": "506e64e710ff9573fd2b86686528762b7901b5e4",
"lessThan": "5286d4eb5cd7e10d7d93c3cc596e18bc8ad80f72",
"versionType": "git",
"status": "affected"
},
{
"version": "506e64e710ff9573fd2b86686528762b7901b5e4",
"lessThan": "cca4980630b3c7a85f53cb43c6018184ce5d4e37",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"kernel/events/core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.15",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.15",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.18.55",
"lessThanOrEqual": "6.18.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "7.2.9",
"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/23250517cd475367653f1e99396967f54c6f1b7c",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5286d4eb5cd7e10d7d93c3cc596e18bc8ad80f72",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/cca4980630b3c7a85f53cb43c6018184ce5d4e37",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}