{"id":"CVE-2022-48940","summary":"bpf: Fix crash due to incorrect copy_map_value","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix crash due to incorrect copy_map_value\n\nWhen both bpf_spin_lock and bpf_timer are present in a BPF map value,\ncopy_map_value needs to skirt both objects when copying a value into and\nout of the map. However, the current code does not set both s_off and\nt_off in copy_map_value, which leads to a crash when e.g. bpf_spin_lock\nis placed in map value with bpf_timer, as bpf_map_update_elem call will\nbe able to overwrite the other timer object.\n\nWhen the issue is not fixed, an overwriting can produce the following\nsplat:\n\n[root@(none) bpf]# ./test_progs -t timer_crash\n[   15.930339] bpf_testmod: loading out-of-tree module taints kernel.\n[   16.037849] ==================================================================\n[   16.038458] BUG: KASAN: user-memory-access in __pv_queued_spin_lock_slowpath+0x32b/0x520\n[   16.038944] Write of size 8 at addr 0000000000043ec0 by task test_progs/325\n[   16.039399]\n[   16.039514] CPU: 0 PID: 325 Comm: test_progs Tainted: G           OE     5.16.0+ #278\n[   16.039983] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.15.0-1 04/01/2014\n[   16.040485] Call Trace:\n[   16.040645]  \u003cTASK\u003e\n[   16.040805]  dump_stack_lvl+0x59/0x73\n[   16.041069]  ? __pv_queued_spin_lock_slowpath+0x32b/0x520\n[   16.041427]  kasan_report.cold+0x116/0x11b\n[   16.041673]  ? __pv_queued_spin_lock_slowpath+0x32b/0x520\n[   16.042040]  __pv_queued_spin_lock_slowpath+0x32b/0x520\n[   16.042328]  ? memcpy+0x39/0x60\n[   16.042552]  ? pv_hash+0xd0/0xd0\n[   16.042785]  ? lockdep_hardirqs_off+0x95/0xd0\n[   16.043079]  __bpf_spin_lock_irqsave+0xdf/0xf0\n[   16.043366]  ? bpf_get_current_comm+0x50/0x50\n[   16.043608]  ? jhash+0x11a/0x270\n[   16.043848]  bpf_timer_cancel+0x34/0xe0\n[   16.044119]  bpf_prog_c4ea1c0f7449940d_sys_enter+0x7c/0x81\n[   16.044500]  bpf_trampoline_6442477838_0+0x36/0x1000\n[   16.044836]  __x64_sys_nanosleep+0x5/0x140\n[   16.045119]  do_syscall_64+0x59/0x80\n[   16.045377]  ? lock_is_held_type+0xe4/0x140\n[   16.045670]  ? irqentry_exit_to_user_mode+0xa/0x40\n[   16.046001]  ? mark_held_locks+0x24/0x90\n[   16.046287]  ? asm_exc_page_fault+0x1e/0x30\n[   16.046569]  ? asm_exc_page_fault+0x8/0x30\n[   16.046851]  ? lockdep_hardirqs_on+0x7e/0x100\n[   16.047137]  entry_SYSCALL_64_after_hwframe+0x44/0xae\n[   16.047405] RIP: 0033:0x7f9e4831718d\n[   16.047602] Code: b4 0c 00 0f 05 eb a9 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 8b 0d b3 6c 0c 00 f7 d8 64 89 01 48\n[   16.048764] RSP: 002b:00007fff488086b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000023\n[   16.049275] RAX: ffffffffffffffda RBX: 00007f9e48683740 RCX: 00007f9e4831718d\n[   16.049747] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fff488086d0\n[   16.050225] RBP: 00007fff488086f0 R08: 00007fff488085d7 R09: 00007f9e4cb594a0\n[   16.050648] R10: 0000000000000000 R11: 0000000000000206 R12: 00007f9e484cde30\n[   16.051124] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000\n[   16.051608]  \u003c/TASK\u003e\n[   16.051762] ==================================================================","modified":"2026-04-02T08:27:10.179539Z","published":"2024-08-22T03:31:35.844Z","related":["SUSE-SU-2024:3190-1","SUSE-SU-2024:3209-1","SUSE-SU-2024:3483-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/48xxx/CVE-2022-48940.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/719d1c2524c89ada78c4c9202641c1d9e942a322"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a8abb0c3dc1e28454851a00f8b7333d9695d566c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eca9bd215d2233de79d930fa97aefbce03247a98"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/48xxx/CVE-2022-48940.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-48940"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"68134668c17f31f51930478f75495b552a411550"},{"fixed":"719d1c2524c89ada78c4c9202641c1d9e942a322"},{"fixed":"eca9bd215d2233de79d930fa97aefbce03247a98"},{"fixed":"a8abb0c3dc1e28454851a00f8b7333d9695d566c"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-48940.json"}}],"schema_version":"1.7.5"}