net: pktgen: fix proc entry use-after-free
In the Linux kernel, the following vulnerability has been resolved: net: pktgen: fix proc entry use-after-free pktgen_change_name() replaces pkt_dev->entry while holding t->if_lock. pktgen_remove_device() removes the same entry before _rem_dev_from_if_list() takes that lock. This allows the following interleaving: CPU 0 (NETDEV_CHANGENAME) CPU 1 (kpktgend) if_lock(t) proc_remove(pkt_dev->entry) proc_remove(pkt_dev->entry) pkt_dev->entry = proc_create_data(...) if_unlock(t) The kthread can pass the stale proc_dir_entry to proc_remove() after the rename path has freed it. A reproducer with a widened race window reports: BUG: KASAN: slab-use-after-free in proc_remove+0x78/0x80 Read of size 8 at addr ffff8881478fea70 by task kpktgend_0/67 Call Trace: proc_remove+0x78/0x80 pktgen_remove_device.isra.0+0x11c/0x4c0 pktgen_thread_worker+0x1214/0x6bc0 kthread+0x2c6/0x3b0 Allocated by task 95: __proc_create+0x204/0x790 proc_create_data+0x72/0xe0 pktgen_thread_write+0xd61/0x1510 Freed by task 28: kmem_cache_free+0xcb/0x3d0 proc_free_inode+0x5b/0x80 rcu_core+0x50a/0x1850 The buggy address belongs to the object at ffff8881478fea00 which belongs to the cache proc_dir_entry of size 192 Move proc_remove() into the if_lock-protected list removal helper. Keep it before list_del_rcu() to preserve the ordering required by add_device(). The rename path must then finish replacing the entry before removal, or it observes that the device is no longer on the list.
CVE-2026-74479
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-2026-74479
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": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "82ed3db9269cb61e3c15bad2f6e221efce90e1e0",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "d1cc9797cf8f7aeb87e7ad01b748c6a960a819e4",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "7991c7cff8b8622cddb3d8dee07dbe74aa4cbec4",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "577443530cb592d5782a1f79847411a9363a65c8",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "f85a58340b91f225de3299dfa782c6414098077c",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "4ef801b838d85c0ea5852c50667f7344ce3b6cd0",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "b006a5404470bd3eb2aa0425fc447183032047ef",
"versionType": "git"
},
{
"status": "affected",
"version": "39df232f1a9ba48d41c68ee7d4046756e709cf91",
"lessThan": "817ff6efdb7f484ea547218e11e17d8e43daa3b4",
"versionType": "git"
}
],
"programFiles": [
"net/core/pktgen.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.22"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.22",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.266",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.217",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.184",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.153",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.105",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.44",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.8",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/core/pktgen.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74479
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #33170 · Revision 1
- Added to Heist Feed
- Publisher date