bpf: Fix invalid prog->stats access when update_effective_progs fails
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.1.160, 6.6.120, 6.12.63, 6.17.13, 6.18.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix invalid prog->stats access when update_effective_progs fails Syzkaller triggers an invalid memory access issue following fault injection in update_effective_progs. The issue can be described as follows: __cgroup_bpf_detach update_effective_progs compute_effective_progs bpf_prog_array_alloc <-- fault inject purge_effective_progs /* change to dummy_bpf_prog */ array->items[index] = &dummy_bpf_prog.prog ---softirq start--- __do_softirq ... __cgroup_bpf_run_filter_skb __bpf_prog_run_save_cb bpf_prog_run stats = this_cpu_ptr(prog->stats) /* invalid memory access */ flags = u64_stats_update_begin_irqsave(&stats->syncp) ---softirq end--- static_branch_dec(&cgroup_bpf_enabled_key[atype]) The reason is that fault injection caused update_effective_progs to fail and then changed the original prog into dummy_bpf_prog.prog in purge_effective_progs. Then a softirq came, and accessing the members of dummy_bpf_prog.prog in the softirq triggers invalid mem access. To fix it, skip updating stats when stats is NULL.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in 93d1964773ff513c9bd530f7686d3e48b786fa6b; From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in bf2c990b012100610c0f1ec5c4ea434da2d080c2; From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in 539137e3038ce6f953efd72110110f03c14c7d97; From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in 56905bb70c8b88421709bb4e32fcba617aa37d41; From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in 2579c356ccd35d06238b176e4b460978186d804b; From 492ecee892c2a4ba6a14903d5d586ff750b7e805 · fixed in 7dc211c1159d991db609bdf4b0fb9033c04adcbc
- Linux Linux
5.1
- KernelLinux
From 5.1.0 · fixed in 6.1.160; From 6.2.0 · fixed in 6.6.120; From 6.7.0 · fixed in 6.12.63; From 6.13.0 · fixed in 6.17.13; From 6.18.0 · fixed in 6.18.2