CVE-2022-49552

high
Published 2023-05-09 ยท Modified 2023-05-09
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
8.0

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix combination of jit blinding and pointers to bpf subprogs. The combination of jit blinding and pointers to bpf subprogs causes: [ 36.989548] BUG: unable to handle page fault for address: 0000000100000001 [ 36.990342] #PF: supervisor instruction fetch in kernel mode [ 36.990968] #PF: error_code(0x0010) - not-present page [ 36.994859] RIP: 0010:0x100000001 [ 36.995209] Code: Unable to access opcode bytes at RIP 0xffffffd7. [ 37.004091] Call Trace: [ 37.004351] <TASK> [ 37.004576] ? bpf_loop+0x4d/0x70 [ 37.004932] ? bpf_prog_3899083f75e4c5de_F+0xe3/0x13b The jit blinding logic didn't recognize that ld_imm64 with an address of bpf subprogram is a special instruction and proceeded to randomize it. By itself it wouldn't have been an issue, but jit_subprogs() logic relies on two step process to JIT all subprogs and then JIT them again when addresses of all subprogs are known. Blinding process in the first JIT phase caused second JIT to miss adjustment of special ld_imm64. Fix this issue by ignoring special ld_imm64 instructions that don't have user controlled constants and shouldn't be blinded.

Predictions

Exploit likelihood
20%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

suse SUSE Affected 1 release
VersionStatusFixed in
โ€” Affected โ€”
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 5.18.2-1
sid Fixed 5.18.2-1
forky Fixed 5.18.2-1
bullseye Fixed 0
bookworm Fixed 5.18.2-1
redhat Red Hat Fixed 1 release
VersionStatusFixed in
9 Fixed โ€”

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.