syzbot has found a reproducer for the following issue on: HEAD commit: ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g.. git tree: upstream console+strace: https://syzkaller.appspot.com/x/log.txt?x=117aa8b0580000 kernel config: https://syzkaller.appspot.com/x/.config?x=31c2647cf06aa81e dashboard link: https://syzkaller.appspot.com/bug?extid=7727bbb9b847a6d3d8de 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=146cdaf8580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15d83818580000
Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/da86466e08c0/disk-ccb98cce.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/673316cfa30c/vmlinux-ccb98cce.xz kernel image: https://storage.googleapis.com/syzbot-assets/4d50a89ed2d4/bzImage-ccb98cce.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/5f0f60916397/mount_2.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7727bbb9b847a6d3d...@syzkaller.appspotmail.com ===================================================== BUG: KMSAN: uninit-value in writepoint_find fs/bcachefs/alloc_foreground.c:1313 [inline] BUG: KMSAN: uninit-value in bch2_alloc_sectors_start_trans+0x44a/0x32b0 fs/bcachefs/alloc_foreground.c:1413 writepoint_find fs/bcachefs/alloc_foreground.c:1313 [inline] bch2_alloc_sectors_start_trans+0x44a/0x32b0 fs/bcachefs/alloc_foreground.c:1413 __bch2_write+0x7f8/0x8540 fs/bcachefs/io_write.c:1437 bch2_write+0xec0/0x1d10 fs/bcachefs/io_write.c:1631 closure_queue include/linux/closure.h:270 [inline] closure_call include/linux/closure.h:432 [inline] bch2_writepage_do_io fs/bcachefs/fs-io-buffered.c:449 [inline] bch2_writepages+0x24a/0x3c0 fs/bcachefs/fs-io-buffered.c:641 do_writepages+0x427/0xc30 mm/page-writeback.c:2702 __writeback_single_inode+0x103/0x1290 fs/fs-writeback.c:1680 writeback_sb_inodes+0xa34/0x1c20 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x14c/0x440 fs/fs-writeback.c:2047 wb_writeback+0x50b/0xcb0 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0x122c/0x1940 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391 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_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:477 [inline] __bch2_writepage+0x39d9/0x3f10 fs/bcachefs/fs-io-buffered.c:599 write_cache_pages+0xc9/0x280 mm/page-writeback.c:2659 bch2_writepages+0x11f/0x3c0 fs/bcachefs/fs-io-buffered.c:639 do_writepages+0x427/0xc30 mm/page-writeback.c:2702 __writeback_single_inode+0x103/0x1290 fs/fs-writeback.c:1680 writeback_sb_inodes+0xa34/0x1c20 fs/fs-writeback.c:1976 __writeback_inodes_wb+0x14c/0x440 fs/fs-writeback.c:2047 wb_writeback+0x50b/0xcb0 fs/fs-writeback.c:2158 wb_check_background_flush fs/fs-writeback.c:2228 [inline] wb_do_writeback fs/fs-writeback.c:2316 [inline] wb_workfn+0x122c/0x1940 fs/fs-writeback.c:2343 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3310 worker_thread+0xea7/0x14f0 kernel/workqueue.c:3391 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: slab_post_alloc_hook mm/slub.c:4125 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_lru_noprof+0x91c/0xe20 mm/slub.c:4187 __bch2_new_inode+0x98/0x450 fs/bcachefs/fs.c:401 bch2_new_inode fs/bcachefs/fs.c:427 [inline] bch2_inode_hash_init_insert+0x7d/0x3a0 fs/bcachefs/fs.c:447 bch2_lookup_trans fs/bcachefs/fs.c:622 [inline] bch2_lookup+0x1605/0x2360 fs/bcachefs/fs.c:659 lookup_open fs/namei.c:3627 [inline] open_last_lookups fs/namei.c:3748 [inline] path_openat+0x292f/0x6200 fs/namei.c:3984 do_filp_open+0x268/0x600 fs/namei.c:4014 do_sys_openat2+0x1bf/0x2f0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x2a1/0x310 fs/open.c:1428 x64_sys_call+0x36f5/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:258 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: 13 Comm: kworker/u8:1 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: writeback wb_workfn (flush-bcachefs-1) ===================================================== --- 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.
