From: syzbot <syzbot+c761143a86b1640bc485@syzkaller.appspotmail.com>
To: kent.overstreet@linux.dev, linux-bcachefs@vger.kernel.org,
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [bcachefs?] KMSAN: uninit-value in bch2_bucket_alloc_trans
Date: Wed, 26 Mar 2025 14:13:28 -0700 [thread overview]
Message-ID: <67e46df8.050a0220.2f068f.000f.GAE@google.com> (raw)
In-Reply-To: <6755b44c.050a0220.2477f.002a.GAE@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: 2df0c02dab82 x86 boot build: make git ignore stale 'tools'..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=135c6a4c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=afd286fb06ecc311
dashboard link: https://syzkaller.appspot.com/bug?extid=c761143a86b1640bc485
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10355804580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16c86198580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4df46ef3da39/disk-2df0c02d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7585a408245b/vmlinux-2df0c02d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2f16d3f20d29/bzImage-2df0c02d.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/e2708f9fb487/mount_5.gz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c761143a86b1640bc485@syzkaller.appspotmail.com
fragmentation 0
bp_start 8
incorrectly set at freespace:0:31:0 (free 0, genbits 0 should be 0), fixing
=====================================================
BUG: KMSAN: uninit-value in try_alloc_bucket fs/bcachefs/alloc_foreground.c:297 [inline]
BUG: KMSAN: uninit-value in bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:442 [inline]
BUG: KMSAN: uninit-value in bch2_bucket_alloc_trans+0x2191/0x3280 fs/bcachefs/alloc_foreground.c:574
try_alloc_bucket fs/bcachefs/alloc_foreground.c:297 [inline]
bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:442 [inline]
bch2_bucket_alloc_trans+0x2191/0x3280 fs/bcachefs/alloc_foreground.c:574
bch2_bucket_alloc_set_trans+0x935/0x1620 fs/bcachefs/alloc_foreground.c:730
__open_bucket_add_buckets+0x1e98/0x3130 fs/bcachefs/alloc_foreground.c:973
open_bucket_add_buckets+0x32b/0x530 fs/bcachefs/alloc_foreground.c:1017
bch2_alloc_sectors_start_trans+0x1839/0x32d0
__bch2_btree_node_alloc fs/bcachefs/btree_update_interior.c:322 [inline]
bch2_btree_reserve_get+0x9eb/0x22b0 fs/bcachefs/btree_update_interior.c:532
bch2_btree_update_start+0x22b8/0x2ec0 fs/bcachefs/btree_update_interior.c:1232
bch2_btree_node_rewrite+0x1da/0x1af0 fs/bcachefs/btree_update_interior.c:2144
async_btree_node_rewrite_trans fs/bcachefs/btree_update_interior.c:2217 [inline]
async_btree_node_rewrite_work+0x74c/0x1aa0 fs/bcachefs/btree_update_interior.c:2253
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xc1d/0x1e80 kernel/workqueue.c:3319
worker_thread+0xea7/0x14f0 kernel/workqueue.c:3400
kthread+0x6b9/0xef0 kernel/kthread.c:464
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Local variable gen.i.i created at:
bch2_bucket_alloc_freelist fs/bcachefs/alloc_foreground.c:442 [inline]
bch2_bucket_alloc_trans+0x1fb2/0x3280 fs/bcachefs/alloc_foreground.c:574
bch2_bucket_alloc_set_trans+0x935/0x1620 fs/bcachefs/alloc_foreground.c:730
CPU: 1 UID: 0 PID: 4283 Comm: kworker/u8:21 Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0 PREEMPT(undef)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: btree_node_rewrite async_btree_node_rewrite_work
=====================================================
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
prev parent reply other threads:[~2025-03-26 21:13 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-08 14:59 [syzbot] [bcachefs?] KMSAN: uninit-value in bch2_bucket_alloc_trans syzbot
2025-03-26 21:13 ` syzbot [this message]
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