{"id":"DEBIAN-CVE-2024-36938","details":"In the Linux kernel, the following vulnerability has been resolved:  bpf, skmsg: Fix NULL pointer dereference in sk_psock_skb_ingress_enqueue  Fix NULL pointer data-races in sk_psock_skb_ingress_enqueue() which syzbot reported [1].  [1] BUG: KCSAN: data-race in sk_psock_drop / sk_psock_skb_ingress_enqueue  write to 0xffff88814b3278b8 of 8 bytes by task 10724 on cpu 1:  sk_psock_stop_verdict net/core/skmsg.c:1257 [inline]  sk_psock_drop+0x13e/0x1f0 net/core/skmsg.c:843  sk_psock_put include/linux/skmsg.h:459 [inline]  sock_map_close+0x1a7/0x260 net/core/sock_map.c:1648  unix_release+0x4b/0x80 net/unix/af_unix.c:1048  __sock_release net/socket.c:659 [inline]  sock_close+0x68/0x150 net/socket.c:1421  __fput+0x2c1/0x660 fs/file_table.c:422  __fput_sync+0x44/0x60 fs/file_table.c:507  __do_sys_close fs/open.c:1556 [inline]  __se_sys_close+0x101/0x1b0 fs/open.c:1541  __x64_sys_close+0x1f/0x30 fs/open.c:1541  do_syscall_64+0xd3/0x1d0  entry_SYSCALL_64_after_hwframe+0x6d/0x75  read to 0xffff88814b3278b8 of 8 bytes by task 10713 on cpu 0:  sk_psock_data_ready include/linux/skmsg.h:464 [inline]  sk_psock_skb_ingress_enqueue+0x32d/0x390 net/core/skmsg.c:555  sk_psock_skb_ingress_self+0x185/0x1e0 net/core/skmsg.c:606  sk_psock_verdict_apply net/core/skmsg.c:1008 [inline]  sk_psock_verdict_recv+0x3e4/0x4a0 net/core/skmsg.c:1202  unix_read_skb net/unix/af_unix.c:2546 [inline]  unix_stream_read_skb+0x9e/0xf0 net/unix/af_unix.c:2682  sk_psock_verdict_data_ready+0x77/0x220 net/core/skmsg.c:1223  unix_stream_sendmsg+0x527/0x860 net/unix/af_unix.c:2339  sock_sendmsg_nosec net/socket.c:730 [inline]  __sock_sendmsg+0x140/0x180 net/socket.c:745  ____sys_sendmsg+0x312/0x410 net/socket.c:2584  ___sys_sendmsg net/socket.c:2638 [inline]  __sys_sendmsg+0x1e9/0x280 net/socket.c:2667  __do_sys_sendmsg net/socket.c:2676 [inline]  __se_sys_sendmsg net/socket.c:2674 [inline]  __x64_sys_sendmsg+0x46/0x50 net/socket.c:2674  do_syscall_64+0xd3/0x1d0  entry_SYSCALL_64_after_hwframe+0x6d/0x75  value changed: 0xffffffff83d7feb0 -\u003e 0x0000000000000000  Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10713 Comm: syz-executor.4 Tainted: G        W          6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024  Prior to this, commit 4cd12c6065df (\"bpf, sockmap: Fix NULL pointer dereference in sk_psock_verdict_data_ready()\") fixed one NULL pointer similarly due to no protection of saved_data_ready. Here is another different caller causing the same issue because of the same reason. So we should protect it with sk_callback_lock read lock because the writer side in the sk_psock_drop() uses \"write_lock_bh(&sk-\u003esk_callback_lock);\".  To avoid errors that could happen in future, I move those two pairs of lock into the sk_psock_data_ready(), which is suggested by John Fastabend.","modified":"2026-09-15T09:03:07.545900501Z","published":"2024-05-30T16:15:16.897Z","upstream":["CVE-2024-36938"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-36938"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.94-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1~bpo11+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36938.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36938.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-36938.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}