Skip to main content
cve.nowby Sazabi
← All vulnerabilities
CVE-2026-74479

net: pktgen: fix proc entry use-after-free

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 5.10.266, 5.15.217, 6.1.184, 6.6.153, 6.12.105, and 2 more
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: total

Summary

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.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: total

  3. Record last updated

Affected versions

  • Linux Linux

    From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in 82ed3db9269cb61e3c15bad2f6e221efce90e1e0; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in d1cc9797cf8f7aeb87e7ad01b748c6a960a819e4; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in 7991c7cff8b8622cddb3d8dee07dbe74aa4cbec4; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in 577443530cb592d5782a1f79847411a9363a65c8; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in f85a58340b91f225de3299dfa782c6414098077c; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in 4ef801b838d85c0ea5852c50667f7344ce3b6cd0; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in b006a5404470bd3eb2aa0425fc447183032047ef; From 39df232f1a9ba48d41c68ee7d4046756e709cf91 · fixed in 817ff6efdb7f484ea547218e11e17d8e43daa3b4

  • Linux Linux

    2.6.22

  • KernelLinux

    From 2.6.22 · fixed in 5.10.266; From 5.11.0 · fixed in 5.15.217; From 5.16.0 · fixed in 6.1.184; From 6.2.0 · fixed in 6.6.153; From 6.7.0 · fixed in 6.12.105; From 6.13.0 · fixed in 6.18.44; From 6.19.0 · fixed in 7.1.8

References 8

git.kernel.org