syzbot


KMSAN: uninit-value in sock_map_delete_elem

Status: upstream: reported C repro on 2024/03/25 13:27
Subsystems: bpf net
[Documentation on labels]
Reported-by: syzbot+eb02dc7f03dce0ef39f3@syzkaller.appspotmail.com
Fix commit: bpf: Mark bpf prog stack with kmsan_unposion_memory in interpreter mode
Patched on: [ci-upstream-bpf-next-kasan-gce ci-upstream-linux-next-kasan-gce-root], missing on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-upstream-bpf-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-net-next-test-gce ci2-upstream-usb]
First crash: 34d, last: 1d04h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH bpf-next] bpf: Mark bpf prog stack with kmsan_unposion_memory in interpreter mode 2 (2) 2024/03/29 02:10
[syzbot] [bpf?] [net?] KMSAN: uninit-value in sock_map_delete_elem 0 (1) 2024/03/25 13:27

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in sock_map_delete_elem+0x15e/0x1c0 net/core/sock_map.c:442
 sock_map_delete_elem+0x15e/0x1c0 net/core/sock_map.c:442
 ____bpf_map_delete_elem kernel/bpf/helpers.c:77 [inline]
 bpf_map_delete_elem+0x5c/0x80 kernel/bpf/helpers.c:73
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
 __bpf_prog_run160+0xb5/0xe0 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run8+0x1bd/0x3a0 kernel/trace/bpf_trace.c:2426
 __bpf_trace_jbd2_handle_stats+0x51/0x70 include/trace/events/jbd2.h:210
 __traceiter_jbd2_handle_stats+0xc5/0x190 include/trace/events/jbd2.h:210
 trace_jbd2_handle_stats include/trace/events/jbd2.h:210 [inline]
 jbd2_journal_stop+0x1157/0x12c0 fs/jbd2/transaction.c:1869
 __ext4_journal_stop+0x115/0x310 fs/ext4/ext4_jbd2.c:134
 ext4_do_writepages+0x1c3c/0x62e0 fs/ext4/inode.c:2692
 ext4_writepages+0x312/0x830 fs/ext4/inode.c:2768
 do_writepages+0x427/0xc30 mm/page-writeback.c:2612
 __writeback_single_inode+0x10d/0x12c0 fs/fs-writeback.c:1650
 writeback_sb_inodes+0xb48/0x1be0 fs/fs-writeback.c:1941
 __writeback_inodes_wb+0x14c/0x440 fs/fs-writeback.c:2012
 wb_writeback+0x4da/0xdf0 fs/fs-writeback.c:2119
 wb_check_old_data_flush fs/fs-writeback.c:2223 [inline]
 wb_do_writeback fs/fs-writeback.c:2276 [inline]
 wb_workfn+0x110c/0x1940 fs/fs-writeback.c:2304
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3335
 worker_thread+0xea5/0x1560 kernel/workqueue.c:3416
 kthread+0x3e2/0x540 kernel/kthread.c:388
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

Local variable stack created at:
 __bpf_prog_run160+0x45/0xe0 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run8+0x1bd/0x3a0 kernel/trace/bpf_trace.c:2426

CPU: 0 PID: 33 Comm: kworker/u8:2 Not tainted 6.8.0-syzkaller-13213-g70293240c5ce #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: writeback wb_workfn (flush-8:0)
=====================================================

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/24 15:16 upstream 70293240c5ce 0ea90952 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/26 02:01 upstream e33c4963bf53 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/20 17:14 upstream 13a2e429f644 af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/07 14:21 upstream f2f80ac80987 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/06 17:29 upstream e8b0ccb2a787 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/02 06:20 upstream 026e680b0a08 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/02 02:30 upstream 39cd87c4eb2b 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/30 08:43 upstream 486291a0e624 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/30 08:43 upstream 486291a0e624 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/29 14:14 upstream 317c7bc0ef03 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/29 01:44 upstream 8d025e2092e2 120789fd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/28 05:35 upstream 962490525cff 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/27 22:25 upstream 7033999ecd7b 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/26 17:08 upstream 928a87efa423 bcd9b39f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/24 05:43 upstream bfa8f18691ed 0ea90952 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/25 19:54 upstream e88c4cfcb7b8 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/20 22:03 upstream 13a2e429f644 af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/15 00:50 upstream 7efd0a74039f c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/04 17:06 upstream c85af715cac0 0ee3535e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/02 13:29 upstream 026e680b0a08 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/04/02 08:32 upstream 026e680b0a08 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/30 08:40 upstream 4535e1a4174c c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/28 05:50 upstream 962490525cff 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
2024/03/26 17:11 upstream 928a87efa423 bcd9b39f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in sock_map_delete_elem
* Struck through repros no longer work on HEAD.