syz.0.0: attempt to access beyond end of device loop0: rw=2049, sector=8672, nr_sectors = 8 limit=0 bcachefs (loop0 inum 4099 offset 770048): data write error: I/O ================================================================== BUG: KASAN: slab-use-after-free in __bch2_write+0x5a72/0x5a80 fs/bcachefs/io_write.c:1439 Read of size 2 at addr ffff88804354effc by task syz.0.0/5325 CPU: 0 UID: 0 PID: 5325 Comm: syz.0.0 Not tainted 6.14.0-rc4-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 __bch2_write+0x5a72/0x5a80 fs/bcachefs/io_write.c:1439 bch2_write+0x865/0x1660 fs/bcachefs/io_write.c:1659 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:469 [inline] bch2_writepages+0x284/0x390 fs/bcachefs/fs-io-buffered.c:652 do_writepages+0x35f/0x880 mm/page-writeback.c:2687 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] file_write_and_wait_range+0x2a3/0x3c0 mm/filemap.c:797 bch2_fsync+0x13a/0x350 fs/bcachefs/fs-io.c:228 generic_write_sync include/linux/fs.h:2970 [inline] bch2_write_iter+0x298a/0x2cd0 fs/bcachefs/fs-io-buffered.c:1072 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1424 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0f3698d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0f377bf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f0f36ba6080 RCX: 00007f0f3698d169 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000008 RBP: 00007f0f36a0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0f36ba6080 R15: 00007ffe42f0bef8 Allocated by task 5325: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4171 mempool_alloc_noprof+0x197/0x5a0 mm/mempool.c:402 bio_alloc_bioset+0x26f/0x1130 block/bio.c:554 bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:485 [inline] __bch2_writepage+0x15f9/0x2750 fs/bcachefs/fs-io-buffered.c:619 write_cache_pages+0xd0/0x230 mm/page-writeback.c:2644 bch2_writepages+0x156/0x390 fs/bcachefs/fs-io-buffered.c:650 do_writepages+0x35f/0x880 mm/page-writeback.c:2687 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] file_write_and_wait_range+0x2a3/0x3c0 mm/filemap.c:797 bch2_fsync+0x13a/0x350 fs/bcachefs/fs-io.c:228 generic_write_sync include/linux/fs.h:2970 [inline] bch2_write_iter+0x298a/0x2cd0 fs/bcachefs/fs-io-buffered.c:1072 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1424 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 1143: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free_after_rcu_debug+0x11a/0x280 mm/slub.c:4659 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2802 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 do_softirq+0x11b/0x1e0 kernel/softirq.c:462 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x312/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548 slab_free_hook mm/slub.c:2314 [inline] slab_free mm/slub.c:4609 [inline] kmem_cache_free+0x2fb/0x410 mm/slub.c:4711 bch2_writepage_io_done+0x86c/0x970 fs/bcachefs/fs-io-buffered.c:461 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Second to last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xaa/0xc0 mm/kasan/generic.c:548 insert_work+0x3e/0x330 kernel/workqueue.c:2183 __queue_work+0xc8b/0xf50 kernel/workqueue.c:2339 queue_work_on+0x1c2/0x380 kernel/workqueue.c:2390 queue_work include/linux/workqueue.h:662 [inline] closure_queue include/linux/closure.h:268 [inline] closure_put_after_sub+0x2b1/0x330 lib/closure.c:42 bch2_nocow_write+0x529e/0x57f0 fs/bcachefs/io_write.c:1396 __bch2_write+0x5850/0x5a80 fs/bcachefs/io_write.c:1438 bch2_write+0x865/0x1660 fs/bcachefs/io_write.c:1659 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:469 [inline] bch2_writepages+0x284/0x390 fs/bcachefs/fs-io-buffered.c:652 do_writepages+0x35f/0x880 mm/page-writeback.c:2687 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] file_write_and_wait_range+0x2a3/0x3c0 mm/filemap.c:797 bch2_fsync+0x13a/0x350 fs/bcachefs/fs-io.c:228 generic_write_sync include/linux/fs.h:2970 [inline] bch2_write_iter+0x298a/0x2cd0 fs/bcachefs/fs-io-buffered.c:1072 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1424 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88804354ef80 which belongs to the cache bio-107 of size 1072 The buggy address is located 124 bytes inside of freed 1072-byte region [ffff88804354ef80, ffff88804354f3b0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4354c head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff888051659500 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff888051659500 dead000000000122 0000000000000000 head: 0000000000000000 00000000800d000d 00000000f5000000 0000000000000000 head: 04fff00000000002 ffffea00010d5301 ffffffffffffffff 0000000000000000 head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2880(GFP_NOWAIT|__GFP_FS|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5325, tgid 5323 (syz.0.0), ts 71790512774, free_ts 71764297449 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2587 new_slab mm/slub.c:2640 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3826 __slab_alloc+0x58/0xa0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] kmem_cache_alloc_noprof+0x268/0x380 mm/slub.c:4171 mempool_alloc_noprof+0x197/0x5a0 mm/mempool.c:402 bio_alloc_bioset+0x26f/0x1130 block/bio.c:554 bch2_writepage_io_alloc fs/bcachefs/fs-io-buffered.c:485 [inline] __bch2_writepage+0x15f9/0x2750 fs/bcachefs/fs-io-buffered.c:619 write_cache_pages+0xd0/0x230 mm/page-writeback.c:2644 bch2_writepages+0x156/0x390 fs/bcachefs/fs-io-buffered.c:650 do_writepages+0x35f/0x880 mm/page-writeback.c:2687 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] file_write_and_wait_range+0x2a3/0x3c0 mm/filemap.c:797 bch2_fsync+0x13a/0x350 fs/bcachefs/fs-io.c:228 page last free pid 5324 tgid 5323 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 discard_slab mm/slub.c:2684 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3153 put_cpu_partial+0x17c/0x250 mm/slub.c:3228 __slab_free+0x290/0x380 mm/slub.c:4479 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_noprof+0x236/0x4c0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] kmalloc_array_noprof include/linux/slab.h:946 [inline] iter_file_splice_write+0x303/0x1510 fs/splice.c:683 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x564/0x8a0 fs/read_write.c:1363 __do_sys_sendfile64 fs/read_write.c:1424 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88804354ee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88804354ef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88804354ef80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804354f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804354f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================