syzbot


KMSAN: uninit-value in bch2_alloc_v4_validate (2)

Status: upstream: reported C repro on 2024/11/17 08:54
Subsystems: bcachefs
[Documentation on labels]
Reported-by: syzbot+8dd95f470e7cd0ff4b66@syzkaller.appspotmail.com
Fix commit: 9c3a2c9b471a bcachefs: Disable asm memcpys when kmsan enabled
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-native-arm64-kvm ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-snapshot-upstream-root ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-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-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-riscv64]
First crash: 179d, last: 48d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bcachefs?] KMSAN: uninit-value in bch2_alloc_v4_validate (2) 0 (3) 2025/04/01 04:00
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in bch2_alloc_v4_validate bcachefs C 5 264d 262d 28/28 fixed on 2024/10/03 15:25

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in bch2_alloc_v4_validate+0x739/0x19a0 fs/bcachefs/alloc_background.c:249
 bch2_alloc_v4_validate+0x739/0x19a0 fs/bcachefs/alloc_background.c:249
 bch2_bkey_val_validate+0x2b5/0x440 fs/bcachefs/bkey_methods.c:143
 bset_key_validate fs/bcachefs/btree_io.c:841 [inline]
 validate_bset_keys+0x1531/0x2080 fs/bcachefs/btree_io.c:910
 validate_bset_for_write+0x142/0x290 fs/bcachefs/btree_io.c:1942
 __bch2_btree_node_write+0x53df/0x6830 fs/bcachefs/btree_io.c:2152
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
 btree_node_write_if_need fs/bcachefs/btree_io.h:151 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:833 [inline]
 btree_interior_update_work+0x3c24/0x4870 fs/bcachefs/btree_update_interior.c:861
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3317
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3398
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 bch2_alloc_v4_validate+0x27f/0x19a0 fs/bcachefs/alloc_background.c:247
 bch2_bkey_val_validate+0x2b5/0x440 fs/bcachefs/bkey_methods.c:143
 bset_key_validate fs/bcachefs/btree_io.c:841 [inline]
 validate_bset_keys+0x1531/0x2080 fs/bcachefs/btree_io.c:910
 validate_bset_for_write+0x142/0x290 fs/bcachefs/btree_io.c:1942
 __bch2_btree_node_write+0x53df/0x6830 fs/bcachefs/btree_io.c:2152
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
 btree_node_write_if_need fs/bcachefs/btree_io.h:151 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:833 [inline]
 btree_interior_update_work+0x3c24/0x4870 fs/bcachefs/btree_update_interior.c:861
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3317
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3398
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was stored to memory at:
 memcpy_u64s_small fs/bcachefs/util.h:393 [inline]
 bkey_p_copy fs/bcachefs/bkey.h:47 [inline]
 bch2_sort_keys_keep_unwritten_whiteouts+0x16af/0x19d0 fs/bcachefs/bkey_sort.c:187
 __bch2_btree_node_write+0x3ae8/0x6830 fs/bcachefs/btree_io.c:2095
 bch2_btree_node_write+0xa5/0x2e0 fs/bcachefs/btree_io.c:2284
 btree_node_write_if_need fs/bcachefs/btree_io.h:151 [inline]
 btree_update_nodes_written fs/bcachefs/btree_update_interior.c:833 [inline]
 btree_interior_update_work+0x3c24/0x4870 fs/bcachefs/btree_update_interior.c:861
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3317
 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3398
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 ___kmalloc_large_node+0x22c/0x370 mm/slub.c:4253
 __kmalloc_large_node_noprof+0x3f/0x1e0 mm/slub.c:4270
 __do_kmalloc_node mm/slub.c:4286 [inline]
 __kmalloc_node_noprof+0xc96/0x1250 mm/slub.c:4304
 __kvmalloc_node_noprof+0xc0/0x2d0 mm/util.c:645
 btree_node_data_alloc fs/bcachefs/btree_cache.c:153 [inline]
 __bch2_btree_node_mem_alloc+0x2be/0xa80 fs/bcachefs/btree_cache.c:198
 bch2_fs_btree_cache_init+0x4e4/0xb50 fs/bcachefs/btree_cache.c:653
 bch2_fs_alloc fs/bcachefs/super.c:917 [inline]
 bch2_fs_open+0x4d3a/0x5b40 fs/bcachefs/super.c:2065
 bch2_fs_get_tree+0x983/0x22d0 fs/bcachefs/fs.c:2157
 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814
 do_new_mount+0x71f/0x15e0 fs/namespace.c:3511
 path_mount+0x742/0x1f10 fs/namespace.c:3838
 do_mount fs/namespace.c:3851 [inline]
 __do_sys_mount fs/namespace.c:4061 [inline]
 __se_sys_mount+0x722/0x810 fs/namespace.c:4038
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4038
 x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 4841 Comm: kworker/u8:26 Not tainted 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Workqueue: btree_update btree_interior_update_work
=====================================================

Crashes (514):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/17 21:50 upstream 9bffa1ad25b8 953d1c45 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/14 05:53 upstream c45323b7560e b1f1cd88 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2024/12/23 06:23 upstream bcde95ce32b6 b4fbdbd4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2024/11/27 12:40 upstream 7eef7e306d3c 52b38cc1 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/15 08:02 upstream c3812b15000c 7315a7cf .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2024/12/17 08:19 upstream f44d154d6e3d f93b2b55 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/24 13:07 upstream 586de92313fc 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/20 10:01 upstream a7f2e10ecd8f 3b7445cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/15 08:04 upstream a29967be967e e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/09 17:27 upstream 1110ce6a1e34 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/07 05:15 upstream 0f52fd4f67c6 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/07 00:56 upstream 848e07631744 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/01 08:27 upstream 7a5668899f54 1e7a43e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/27 17:41 upstream dd83757f6e68 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/27 12:19 upstream 5394eea10651 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/27 10:56 upstream 5394eea10651 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/25 11:52 upstream d082ecbc71e9 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/21 21:59 upstream 334426094588 0808a665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/18 22:59 upstream 6537cfb395f3 c37c7249 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/17 13:54 upstream 0ad2507d5d93 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/16 02:58 upstream 496659003dac 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/13 14:15 upstream 4dc1d1bec898 2afad16e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/10 17:39 upstream a64dcfb451e2 43f51a00 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/09 20:33 upstream 9946eaf552b1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/09 03:06 upstream 493f3f38da21 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/08 14:14 upstream 8f6629c004b1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/08 06:46 upstream 7ee983c850b4 a4f327c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/08 05:32 upstream 7ee983c850b4 a4f327c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/01 17:00 upstream 60c828cf80c0 0dff8567 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/30 16:09 upstream 72deda0abee6 9c8ab845 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/27 19:10 upstream 9c5968db9e62 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/26 18:53 upstream aa22f4da2a46 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/16 15:38 upstream 31d7109a19f6 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/16 13:51 upstream 31d7109a19f6 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/14 11:53 upstream 4003c9e78778 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/09 08:03 upstream b7c90e3e717a 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/09 06:56 upstream b7c90e3e717a 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/07 23:19 upstream 00a7d39898c8 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/07 07:42 upstream f315296c92fd 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/06 18:47 upstream 848e07631744 831e3629 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/03/05 13:50 upstream 48a5eed9ad58 60f5d8d9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/28 07:14 upstream 1e15510b71c9 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/22 10:45 upstream ff202c5028a1 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/21 17:34 upstream 334426094588 0808a665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/19 21:52 upstream 6537cfb395f3 cbd8edab .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/16 21:45 upstream ad1b832bf1cf 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/15 06:18 upstream 04f41cbf03ec 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/02/14 14:09 upstream 128c8f96eb86 d9a046cf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/30 08:57 upstream ebbb8be421ee afe4eff5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/28 09:29 upstream 805ba04cb7cc 18070896 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/26 08:00 upstream 405057718a1f 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2025/01/22 12:08 upstream 62de6e168526 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2024/11/13 08:52 upstream 3022e9d00ebe 62026c85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
2024/11/13 08:47 upstream 3022e9d00ebe 62026c85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in bch2_alloc_v4_validate
* Struck through repros no longer work on HEAD.