linux — security advisory
In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Fix memory leak problem This reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac. As commit 46bbe5c671e0 ("tracing: fix double free") said, the "double free" problem reported by clang static analyzer is: > In parse_var_defs() if there is a problem allocating > var_defs.expr, the earlier var_defs.name is freed. > This free is duplicated by free_var_defs() which frees > the rest of the list. However, if there is a problem allocating N-th var_defs.expr: + in parse_var_defs(), the freed 'earlier var_defs.name' is actually the N-th var_defs.name; + then in free_var_defs(), the names from 0th to (N-1)-th are freed; IF ALLOCATING PROBLEM HAPPENED HERE!!! -+ \ | 0th 1th (N-1)-th N-th V +-------------+-------------+-----+-------------+----------- var_defs: | name | expr | name | expr | ... | name | expr | name | /// +-------------+-------------+-----+-------------+----------- These two frees don't act on same name, so there was no "double free" problem before. Conversely, after that commit, we get a "memory leak" problem because the above "N-th var_defs.name" is not freed. If enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th var_defs.expr allocated, then execute on shell like: $ echo 'hist:key=call_site:val=$v1,$v2:v1=bytes_req,v2=bytes_alloc' > \ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger Then kmemleak reports: unreferenced object 0xffff8fb100ef3518 (size 8): comm "b
- Products
- linux
- Affected versions
- Not specified
- Fixed versions
- 5.18.14-1
- CVEs
- CVE-2022-49648
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 15:26 UTC · Revision 1
Source evidence
In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Fix memory leak problem This reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac. As commit 46bbe5c671e0 ("tracing: fix double free") said, the "double free" problem reported by clang static analyzer is: > In parse_var_defs() if there is a problem allocating > var_defs.expr, the earlier var_defs.name is freed. > This free is duplicated by free_var_defs() which frees > the rest of the list. However, if there is a problem allocating N-th var_defs.expr: + in parse_var_defs(), the freed 'earlier var_defs.name' is actually the N-th var_defs.name; + then in free_var_defs(), the names from 0th to (N-1)-th are freed; IF ALLOCATING PROBLEM HAPPENED HERE!!! -+ \ | 0th 1th (N-1)-th N-th V +-------------+-------------+-----+-------------+----------- var_defs: | name | expr | name | expr | ... | name | expr | name | /// +-------------+-------------+-----+-------------+----------- These two frees don't act on same name, so there was no "double free" problem before. Conversely, after that commit, we get a "memory leak" problem because the above "N-th var_defs.name" is not freed. If enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th var_defs.expr allocated, then execute on shell like: $ echo 'hist:key=call_site:val=$v1,$v2:v1=bytes_req,v2=bytes_alloc' > \ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger Then kmemleak reports: unreferenced object 0xffff8fb100ef3518 (size 8): comm "b
osv:DEBIAN-CVE-2022-49648
linux
Fixed versions: 5.18.14-1
linux
Fixed versions: 5.18.14-1
linux
Fixed versions: 5.18.14-1
Complete source record
{
"id": "c015ccb1a597477c18736510d67a1ee2d6cbcdc89a55230c565c2d32002483d4",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2022-49648",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2022-49648",
"summary": "In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Fix memory leak problem This reverts commit 46bbe5c671e06f070428b9be142cc4ee5cedebac. As commit 46bbe5c671e0 (\"tracing: fix double free\") said, the \"double free\" problem reported by clang static analyzer is: > In parse_var_defs() if there is a problem allocating > var_defs.expr, the earlier var_defs.name is freed. > This free is duplicated by free_var_defs() which frees > the rest of the list. However, if there is a problem allocating N-th var_defs.expr: + in parse_var_defs(), the freed 'earlier var_defs.name' is actually the N-th var_defs.name; + then in free_var_defs(), the names from 0th to (N-1)-th are freed; IF ALLOCATING PROBLEM HAPPENED HERE!!! -+ \\ | 0th 1th (N-1)-th N-th V +-------------+-------------+-----+-------------+----------- var_defs: | name | expr | name | expr | ... | name | expr | name | /// +-------------+-------------+-----+-------------+----------- These two frees don't act on same name, so there was no \"double free\" problem before. Conversely, after that commit, we get a \"memory leak\" problem because the above \"N-th var_defs.name\" is not freed. If enable CONFIG_DEBUG_KMEMLEAK and inject a fault at where the N-th var_defs.expr allocated, then execute on shell like: $ echo 'hist:key=call_site:val=$v1,$v2:v1=bytes_req,v2=bytes_alloc' > \\ /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger Then kmemleak reports: unreferenced object 0xffff8fb100ef3518 (size 8): comm \"b",
"evidence": "osv:DEBIAN-CVE-2022-49648",
"products": [
{
"name": {
"value": "linux",
"evidence": "/affected/0/package/name"
},
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},
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"severity": "medium",
"structured": {
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"aliases": [
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"metrics": [
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"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
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"affected": [
{
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"package": {
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"ecosystem": "Debian:12"
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{
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"package": {
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"ecosystem": "Debian:13"
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"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2022-49648.json"
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"package": {
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],
"modified": "2026-10-15T08:02:59.357678357Z",
"provider": "osv",
"upstream": [
"CVE-2022-49648"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2022-49648"
]
},
"related_cves": [
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"evidence": "/upstream"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 324845,
"published_at": "2025-02-26T07:01:39.957+00:00"
}