CVE-2026-64352: bpf: Allow LPM map access from sleepable BPF programs

High 7.8 EPSS 0.1% Linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Allow LPM map access from sleepable BPF programs trie_lookup_elem() annotates its rcu_dereference_check() walks with only rcu_read_lock_bh_held(). Because rcu_dereference_check(p, c) resolves to "c || rcu_read_lock_held()", this passes for XDP/NAPI and classic RCU readers but fails for sleepable BPF programs, which enter via __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace(). trie_update_elem() and trie_delete_elem() have the same problem in a different form: they walk the trie with plain rcu_dereference(), which asserts rcu_read_lock_held() unconditionally. Both are reachable from sleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem helpers, and from the syscall path under classic rcu_read_lock(). In the writer paths the trie is actually protected by trie->lock (an rqspinlock taken across the walk); we never relied on the RCU read-side lock to keep nodes alive there. A sleepable LSM hook that ends up touching an LPM trie therefore triggers lockdep on debug kernels: ============================= WARNING: suspicious RCU usage 7.1.0-... Tainted: G E ----------------------------- kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage! 1 lock held by net_tests/540: #0: (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_enter_sleepable+0x26/0x280 Call Trace: dump_stack_lvl lockdep_rcu_suspicious trie_lookup_elem bpf_prog_..._enforce_security_socket_connect bpf_trampoline_... security_socket_connect __sys_connect do_syscall_64 This is lockdep-only -- no UAF, since Tasks Trace RCU does serialize against the trie's reclaim path -- but it spams the console once per distinct callsite on every debug kernel running a sleepable BPF LSM that touches an LPM trie, which is increasingly common. For the lookup path, switch the rcu_dereference_check() annotation from rcu_read_lock_bh_held() to bpf_rcu_lock_held(), which accepts all three contexts (classic, BH, Tasks Trace). Other map types already follow this convention. For trie_update_elem() and trie_delete_elem(), annotate the walks as rcu_dereference_protected(*p, 1) -- matching trie_free() in the same file -- since trie->lock is held across the walk. rqspinlock has no lockdep_map, so the predicate degenerates to '1' rather than lockdep_is_held(&trie->lock); the protection is real but not machine-verifiable. trie_get_next_key() also uses bare rcu_dereference() but is reachable only from the BPF syscall, which holds classic rcu_read_lock() before dispatching, so it is left untouched.

• CVE-2026-64352CVE identifier
• 7.8CVSS 3.1 base score (high)
• 0.1%EPSS: chance of exploitation in the next 30 days (higher than 3% of CVEs)
• 2026-07-25published

What do these terms mean? CVE · CVSS score · exploited (KEV) · EPSS · backported fix · all terms

Affected and fixed versions

Affected:

• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before 304ca50582f0c047370f85e13caec456f78c9fcc
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before ec662a8b2cde01e76b37ccd4b992d0342299e69c
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before 9bfdf4b81b0e56d47bc6c46c34a46638be716695
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before 57454944737f3ad9a8703aecbbb79713b513a94b
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before bd6ad9a6b30498d845413e863fb95c6fab3babe3
• Linux Linux 694cea395fded425008e93cd90cfdf7a451674af to before 2f884d371fafea137afea504d49ee4a7c8d7985b
• Linux Linux 5.14

Patch it

Use the commands for your system. Distribution packages often keep an older version number with the fix backported, so compare with the fixed package versions in the table below, not only with the upstream version.

sudo apt update
sudo apt install --only-upgrade linux-image-amd64

sudo apt update
sudo apt install --only-upgrade linux-image-generic (or the installed flavour: linux-image-aws, -azure, -gcp, -virtual)

sudo dnf upgrade --refresh kernel

sudo dnf upgrade --refresh kernel

sudo zypper refresh
sudo zypper update kernel-default

sudo dnf upgrade --releasever=latest kernel kernel6.12

sudo pacman -Syu

apk update && apk upgrade linux-lts linux-virt

not Linux

General update steps for every system are on the Linux and Unix & BSD pages; after updating, see which services to restart.

Fix status in Linux distributions

From the Debian security tracker, Ubuntu CVE tracker and Red Hat Security Data API, refreshed every few hours.

Sources

• https://git.kernel.org/stable/c/f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04
• https://git.kernel.org/stable/c/304ca50582f0c047370f85e13caec456f78c9fcc
• https://git.kernel.org/stable/c/ec662a8b2cde01e76b37ccd4b992d0342299e69c
• https://git.kernel.org/stable/c/9bfdf4b81b0e56d47bc6c46c34a46638be716695
• https://git.kernel.org/stable/c/57454944737f3ad9a8703aecbbb79713b513a94b
• https://git.kernel.org/stable/c/bd6ad9a6b30498d845413e863fb95c6fab3babe3
• https://git.kernel.org/stable/c/2f884d371fafea137afea504d49ee4a7c8d7985b
• CVE-2026-64352 on CVE.org
• CVE-2026-64352 on NVD

Page generated automatically from official sources on 2026-11-03 18:05 UTC. Always confirm with your vendor's advisory.