CVE-2022-49973
Description
In the Linux kernel, the following vulnerability has been resolved: skmsg: Fix wrong last sg check in sk_msg_recvmsg() Fix one kernel NULL pointer dereference as below: [ 224.462334] Call Trace: [ 224.462394] __tcp_bpf_recvmsg+0xd3/0x380 [ 224.462441] ? sock_has_perm+0x78/0xa0 [ 224.462463] tcp_bpf_recvmsg+0x12e/0x220 [ 224.462494] inet_recvmsg+0x5b/0xd0 [ 224.462534] __sys_recvfrom+0xc8/0x130 [ 224.462574] ? syscall_trace_enter+0x1df/0x2e0 [ 224.462606] ? __do_page_fault+0x2de/0x500 [ 224.462635] __x64_sys_recvfrom+0x24/0x30 [ 224.462660] do_syscall_64+0x5d/0x1d0 [ 224.462709] entry_SYSCALL_64_after_hwframe+0x65/0xca In commit 9974d37ea75f ("skmsg: Fix invalid last sg check in sk_msg_recvmsg()"), we change last sg check to sg_is_last(), but in sockmap redirection case (without stream_parser/stream_verdict/ skb_verdict), we did not mark the end of the scatterlist. Check the sk_msg_alloc, sk_msg_page_add, and bpf_msg_push_data functions, they all do not mark the end of sg. They are expected to use sg.end for end judgment. So the judgment of '(i != msg_rx->sg.end)' is added back here.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2022-49973
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2022-49973.html
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2023:2458
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 6.0.2-1 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.0.2-1 |
| debian | sid | fixed | 6.0.2-1 |
| debian | trixie | fixed | 6.0.2-1 |
References
Verify integrity in audit chain (admin only). AS-IS.