bpf: Copy per-CPU map value padding in copy_map_value_long()
In the Linux kernel, the following vulnerability has been resolved: bpf: Copy per-CPU map value padding in copy_map_value_long() In kernel, per-CPU map elements are stored with round_up(map->value_size, 8) bytes. On UAPI lookup paths, it copies the rounded size for each CPU into a temporary buffer. However, copy_map_value_long() passes 'map->value_size' to bpf_obj_memcpy(). When the map has special fields, bpf_obj_memcpy() copies around those fields with memcpy(), and does not copy the tail padding between 'map->value_size' and round_up(map->value_size, 8). The temporary UAPI lookup buffers are allocated without __GFP_ZERO. As a result, when the per-CPU map's value size is not equal to round_up(map->value_size, 8), UAPI LOOKUP_ELEM and its variants can return stale heap contents from that padding to user space. The same issue applies to bpf_iter for per-CPU maps. Pass round_up(map->value_size, 8) to bpf_obj_memcpy() from copy_map_value_long(), so per-CPU maps both with and without special fields copy the entire per-CPU slot. Remove the now redundant round_up() from bpf_obj_memcpy()'s long_memcpy path.
CVE-2026-93174
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-2026-93174
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": "448325199f574d33824dbf9121efb03558412966",
"lessThan": "953e85da53541a8dc3e7ad4e8532f29a34a32eae",
"versionType": "git"
},
{
"status": "affected",
"version": "448325199f574d33824dbf9121efb03558412966",
"lessThan": "003bf840ed3326bd01396ce7d5b431cef0d371e7",
"versionType": "git"
},
{
"status": "affected",
"version": "448325199f574d33824dbf9121efb03558412966",
"lessThan": "5e9f69829835521aa2942d1d14bd0990fbc6991e",
"versionType": "git"
},
{
"status": "affected",
"version": "448325199f574d33824dbf9121efb03558412966",
"lessThan": "ff3f22ed8d2f350b4c24ee26e33daea5f08d58ef",
"versionType": "git"
},
{
"status": "affected",
"version": "448325199f574d33824dbf9121efb03558412966",
"lessThan": "7cf9cd98cf6f0df3befc167ca6b54c07014d71de",
"versionType": "git"
}
],
"programFiles": [
"include/linux/bpf.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.1"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.1",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.110",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.52",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.6",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/linux/bpf.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-93174
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #37888 · Revision 1
- Added to Heist Feed
- Publisher date