syzbot


KMSAN: uninit-value in percpu_array_map_lookup_elem

Status: closed as dup on 2024/04/09 05:37
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+5e23b0df3b12b8b215b7@syzkaller.appspotmail.com
First crash: 36d, last: 19d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KMSAN: uninit-value in dev_map_lookup_elem bpf net C 3 20d 26d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bpf?] KMSAN: uninit-value in percpu_array_map_lookup_elem 1 (2) 2024/04/09 05:37

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in percpu_array_map_lookup_elem+0x142/0x160 kernel/bpf/arraymap.c:243
 percpu_array_map_lookup_elem+0x142/0x160 kernel/bpf/arraymap.c:243
 ____bpf_map_lookup_elem kernel/bpf/helpers.c:42 [inline]
 bpf_map_lookup_elem+0x5c/0x80 kernel/bpf/helpers.c:38
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
 __bpf_prog_run64+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_run3+0x132/0x320 kernel/trace/bpf_trace.c:2421
 __bpf_trace_ext4_es_insert_delayed_block+0x34/0x50 include/trace/events/ext4.h:2481
 trace_ext4_es_insert_delayed_block include/trace/events/ext4.h:2481 [inline]
 ext4_es_insert_delayed_block+0x11e1/0x1290 fs/ext4/extents_status.c:2082
 ext4_insert_delayed_block fs/ext4/inode.c:1676 [inline]
 ext4_da_map_blocks fs/ext4/inode.c:1777 [inline]
 ext4_da_get_block_prep+0x1714/0x1d30 fs/ext4/inode.c:1817
 ext4_block_write_begin+0x749/0x1df0 fs/ext4/inode.c:1055
 ext4_da_write_begin+0x889/0xec0 fs/ext4/inode.c:2894
 generic_perform_write+0x400/0xc60 mm/filemap.c:3974
 ext4_buffered_write_iter+0x564/0xaa0 fs/ext4/file.c:299
 ext4_file_write_iter+0x208/0x3450
 call_write_iter include/linux/fs.h:2108 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xb63/0x1520 fs/read_write.c:590
 ksys_write+0x20f/0x4c0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x93/0xe0 fs/read_write.c:652
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Local variable stack created at:
 __bpf_prog_run64+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_run3+0x132/0x320 kernel/trace/bpf_trace.c:2421

CPU: 1 PID: 5001 Comm: syz-executor118 Not tainted 6.8.0-syzkaller-09791-ge5eb28f6d1af #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
=====================================================

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/16 05:10 upstream e5eb28f6d1af d615901c .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/04/01 21:46 upstream 39cd87c4eb2b 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/29 22:41 upstream 317c7bc0ef03 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/27 18:12 upstream 7033999ecd7b 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/17 20:59 upstream 741e9d668aa5 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/16 02:21 upstream e5eb28f6d1af d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/04/01 21:48 upstream 39cd87c4eb2b 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/29 22:48 upstream 317c7bc0ef03 c52bcb23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/27 18:13 upstream 7033999ecd7b 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/17 20:55 upstream 741e9d668aa5 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in percpu_array_map_lookup_elem
2024/03/17 20:38 upstream 741e9d668aa5 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in percpu_array_map_lookup_elem
* Struck through repros no longer work on HEAD.