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KASAN: use-after-free Read in iomap_finish_ioend

Status: auto-obsoleted due to no activity on 2024/10/13 23:34
Reported-by: syzbot+12141bca62eb3237e50c@syzkaller.appspotmail.com
First crash: 140d, last: 140d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in iomap_finish_ioend 1 595d 595d 0/3 auto-obsoleted due to no activity on 2023/08/06 06:24
upstream KASAN: slab-use-after-free Read in iomap_finish_ioend iomap 1 594d 590d 0/28 auto-obsoleted due to no activity on 2023/08/07 07:45

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in iomap_finish_ioend+0x898/0x960 fs/iomap/buffered-io.c:1319
Read of size 8 at addr ffff88805e191950 by task kworker/0:12/4394

CPU: 0 PID: 4394 Comm: kworker/0:12 Not tainted 6.1.97-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: xfs-conv/loop1 xfs_end_io
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 iomap_finish_ioend+0x898/0x960 fs/iomap/buffered-io.c:1319
 iomap_finish_ioends+0x1ab/0x390 fs/iomap/buffered-io.c:1343
 xfs_end_ioend+0x36e/0x4d0 fs/xfs/xfs_aops.c:134
 xfs_end_io+0x2e1/0x370 fs/xfs/xfs_aops.c:171
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>

Allocated by task 6324:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x10c/0x2d0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3193 [inline]
 xfs_inode_alloc+0x84/0x6c0 fs/xfs/xfs_icache.c:81
 xfs_iget_cache_miss fs/xfs/xfs_icache.c:590 [inline]
 xfs_iget+0xbe5/0x3360 fs/xfs/xfs_icache.c:756
 xfs_lookup+0x2b2/0x4e0 fs/xfs/xfs_inode.c:669
 xfs_vn_lookup+0x18e/0x290 fs/xfs/xfs_iops.c:304
 lookup_open fs/namei.c:3462 [inline]
 open_last_lookups fs/namei.c:3552 [inline]
 path_openat+0x10fb/0x2e60 fs/namei.c:3782
 do_filp_open+0x230/0x480 fs/namei.c:3812
 do_sys_openat2+0x13b/0x500 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 3003:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 rcu_do_batch kernel/rcu/tree.c:2296 [inline]
 rcu_core+0xad5/0x1810 kernel/rcu/tree.c:2556
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 __do_softirq kernel/softirq.c:605 [inline]
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:654
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:666
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2844
 __xfs_inode_free fs/xfs/xfs_icache.c:161 [inline]
 xfs_reclaim_inode fs/xfs/xfs_icache.c:958 [inline]
 xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1640 [inline]
 xfs_icwalk_ag+0x13c4/0x1b70 fs/xfs/xfs_icache.c:1722
 xfs_icwalk fs/xfs/xfs_icache.c:1771 [inline]
 xfs_reclaim_inodes+0x1f3/0x300 fs/xfs/xfs_icache.c:991
 xfs_unmount_flush_inodes+0xaf/0xc0 fs/xfs/xfs_mount.c:594
 xfs_unmountfs+0xc0/0x280 fs/xfs/xfs_mount.c:1071
 xfs_fs_put_super+0x6c/0x2c0 fs/xfs/xfs_super.c:1118
 generic_shutdown_super+0x130/0x340 fs/super.c:501
 kill_block_super+0x7a/0xe0 fs/super.c:1459
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 insert_work+0x54/0x3d0 kernel/workqueue.c:1361
 __queue_work+0xb4b/0xf90 kernel/workqueue.c:1520
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1548
 queue_work include/linux/workqueue.h:512 [inline]
 xfs_end_bio+0xf2/0x1d0 fs/xfs/xfs_aops.c:186
 iomap_submit_ioend fs/iomap/buffered-io.c:1458 [inline]
 iomap_writepages+0x1e3/0x240 fs/iomap/buffered-io.c:1790
 xfs_vm_writepages+0x135/0x190 fs/xfs/xfs_aops.c:503
 do_writepages+0x3a2/0x670 mm/page-writeback.c:2469
 filemap_fdatawrite_wbc+0x121/0x180 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 file_write_and_wait_range+0x1ca/0x2b0 mm/filemap.c:774
 xfs_file_fsync+0x1e5/0xae0 fs/xfs/xfs_file.c:151
 generic_write_sync include/linux/fs.h:2957 [inline]
 xfs_file_buffered_write+0xaa6/0xbe0 fs/xfs/xfs_file.c:764
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88805e191740
 which belongs to the cache xfs_inode of size 1808
The buggy address is located 528 bytes inside of
 1808-byte region [ffff88805e191740, ffff88805e191e50)

The buggy address belongs to the physical page:
page:ffffea0001786400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805e192e80 pfn:0x5e190
head:ffffea0001786400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888074fe1a01
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8881482b3a00
raw: ffff88805e192e80 0000000080100007 00000001ffffffff ffff888074fe1a01
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 3847, tgid 3846 (syz.1.68), ts 70468473485, free_ts 69374753787
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517
 prep_new_page mm/page_alloc.c:2524 [inline]
 get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4283
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5551
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc_lru+0x1a5/0x2d0 mm/slub.c:3429
 alloc_inode_sb include/linux/fs.h:3193 [inline]
 xfs_inode_alloc+0x84/0x6c0 fs/xfs/xfs_icache.c:81
 xfs_iget_cache_miss fs/xfs/xfs_icache.c:590 [inline]
 xfs_iget+0xbe5/0x3360 fs/xfs/xfs_icache.c:756
 xfs_mountfs+0xf57/0x1f00 fs/xfs/xfs_mount.c:848
 xfs_fs_fill_super+0x1145/0x13a0 fs/xfs/xfs_super.c:1681
 get_tree_bdev+0x3fe/0x620 fs/super.c:1355
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1444 [inline]
 free_pcp_prepare mm/page_alloc.c:1494 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3362
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3457
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:682 [inline]
 locks_alloc_lock fs/locks.c:270 [inline]
 flock_lock_inode+0x226/0x1910 fs/locks.c:1023
 flock_lock_inode_wait fs/locks.c:2034 [inline]
 locks_lock_inode_wait+0x104/0x450 fs/locks.c:2061
 locks_lock_file_wait include/linux/fs.h:1365 [inline]
 __do_sys_flock fs/locks.c:2131 [inline]
 __se_sys_flock+0x4fc/0x660 fs/locks.c:2085
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88805e191800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805e191880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805e191900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88805e191980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805e191a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/05 21:50 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in iomap_finish_ioend
2024/07/05 21:45 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in iomap_finish_ioend
2024/07/05 23:33 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in iomap_finish_ioend
* Struck through repros no longer work on HEAD.