linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: perf/core: Add RCU read lock protection to perf_iterate_ctx() The perf_iterate_ctx() function performs RCU list traversal but currently lacks RCU read lock protection. This causes lockdep warnings when running perf probe with unshare(1) under CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage kernel/events/core.c:8168 RCU-list traversed in non-reader section!! Call Trace: lockdep_rcu_suspicious ? perf_event_addr_filters_apply perf_iterate_ctx perf_event_exec begin_new_exec ? load_elf_phdrs load_elf_binary ? lock_acquire ? find_held_lock ? bprm_execve bprm_execve do_execveat_common.isra.0 __x64_sys_execve do_syscall_64 entry_SYSCALL_64_after_hwframe This protection was previously present but was removed in commit bd2756811766 ("perf: Rewrite core context handling"). Add back the necessary rcu_read_lock()/rcu_read_unlock() pair around perf_iterate_ctx() call in perf_event_exec(). [ mingo: Use scoped_guard() as suggested by Peter ]
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 6.12.19-1
- CVEs
- CVE-2025-21889
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 19:59 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: perf/core: Add RCU read lock protection to perf_iterate_ctx() The perf_iterate_ctx() function performs RCU list traversal but currently lacks RCU read lock protection. This causes lockdep warnings when running perf probe with unshare(1) under CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage kernel/events/core.c:8168 RCU-list traversed in non-reader section!! Call Trace: lockdep_rcu_suspicious ? perf_event_addr_filters_apply perf_iterate_ctx perf_event_exec begin_new_exec ? load_elf_phdrs load_elf_binary ? lock_acquire ? find_held_lock ? bprm_execve bprm_execve do_execveat_common.isra.0 __x64_sys_execve do_syscall_64 entry_SYSCALL_64_after_hwframe This protection was previously present but was removed in commit bd2756811766 ("perf: Rewrite core context handling"). Add back the necessary rcu_read_lock()/rcu_read_unlock() pair around perf_iterate_ctx() call in perf_event_exec(). [ mingo: Use scoped_guard() as suggested by Peter ]
osv:DEBIAN-CVE-2025-21889
linux
Fixed versions: 6.12.19-1
linux
Fixed versions: 6.12.19-1
Complete source record
{
"id": "8969d829c7d6a7bab610beb175ca7e35878b114712e8375daf70cc1fc1ed7a35",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-21889",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2025-21889",
"summary": "In the Linux kernel, the following vulnerability has been resolved: perf/core: Add RCU read lock protection to perf_iterate_ctx() The perf_iterate_ctx() function performs RCU list traversal but currently lacks RCU read lock protection. This causes lockdep warnings when running perf probe with unshare(1) under CONFIG_PROVE_RCU_LIST=y: WARNING: suspicious RCU usage kernel/events/core.c:8168 RCU-list traversed in non-reader section!! Call Trace: lockdep_rcu_suspicious ? perf_event_addr_filters_apply perf_iterate_ctx perf_event_exec begin_new_exec ? load_elf_phdrs load_elf_binary ? lock_acquire ? find_held_lock ? bprm_execve bprm_execve do_execveat_common.isra.0 __x64_sys_execve do_syscall_64 entry_SYSCALL_64_after_hwframe This protection was previously present but was removed in commit bd2756811766 (\"perf: Rewrite core context handling\"). Add back the necessary rcu_read_lock()/rcu_read_unlock() pair around perf_iterate_ctx() call in perf_event_exec(). [ mingo: Use scoped_guard() as suggested by Peter ]",
"evidence": "osv:DEBIAN-CVE-2025-21889",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
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"evidence": "/affected/0/ranges"
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"affected_versions": []
},
{
"name": {
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"fixed_versions": [
{
"value": "6.12.19-1",
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],
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}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2025-21889",
"aliases": [
"DEBIAN-CVE-2025-21889"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "6.12.19-1"
}
]
}
],
"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21889.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
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"type": "ECOSYSTEM",
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{
"introduced": "0"
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{
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],
"package": {
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"purl": "pkg:deb/debian/linux?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21889.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-16T09:47:34.551331337Z",
"provider": "osv",
"upstream": [
"CVE-2025-21889"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2025-21889"
]
},
"related_cves": [
{
"value": "CVE-2025-21889",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 338649,
"published_at": "2025-03-27T15:15:56.82+00:00"
}