syzbot


KASAN: slab-use-after-free Read in do_xmote

Status: moderation: reported on 2024/06/10 18:27
Subsystems: gfs2
[Documentation on labels]
Reported-by: syzbot+04b456c87326d2f56407@syzkaller.appspotmail.com
First crash: 11d, last: 11d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in do_xmote gfs2 C error unreliable 16 503d 625d 0/27 auto-obsoleted due to no activity on 2023/05/31 20:52
linux-6.1 BUG: unable to handle kernel paging request in do_xmote origin:lts-only C inconclusive 3 57d 59d 0/3 upstream: reported C repro on 2024/04/19 23:45

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in is_system_glock fs/gfs2/glock.c:699 [inline]
BUG: KASAN: slab-use-after-free in do_xmote+0xd88/0xe20 fs/gfs2/glock.c:814
Read of size 8 at addr ffff888000ae04b8 by task kworker/0:0H/9

CPU: 0 PID: 9 Comm: kworker/0:0H Not tainted 6.10.0-rc2-syzkaller-00097-g2df0193e62cf #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: glock_workqueue glock_work_func
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 is_system_glock fs/gfs2/glock.c:699 [inline]
 do_xmote+0xd88/0xe20 fs/gfs2/glock.c:814
 run_queue+0x3f0/0x6b0 fs/gfs2/glock.c:900
 glock_work_func+0x127/0x3e0 fs/gfs2/glock.c:1133
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5361:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3940 [inline]
 slab_alloc_node mm/slub.c:4000 [inline]
 kmem_cache_alloc_lru_noprof+0x121/0x2f0 mm/slub.c:4019
 gfs2_alloc_inode+0x49/0x1f0 fs/gfs2/super.c:1537
 alloc_inode+0x5d/0x230 fs/inode.c:261
 iget5_locked fs/inode.c:1235 [inline]
 iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
 gfs2_inode_lookup+0xd1/0x8a0 fs/gfs2/inode.c:124
 gfs2_dir_search+0x22c/0x2e0 fs/gfs2/dir.c:1667
 gfs2_lookupi+0x3c5/0x6d0 fs/gfs2/inode.c:340
 gfs2_lookup_meta+0xa8/0x180 fs/gfs2/inode.c:280
 init_statfs fs/gfs2/ops_fstype.c:631 [inline]
 init_journal fs/gfs2/ops_fstype.c:797 [inline]
 init_inodes+0xf60/0x2e80 fs/gfs2/ops_fstype.c:865
 gfs2_fill_super+0x1a6e/0x2b60 fs/gfs2/ops_fstype.c:1244
 get_tree_bdev+0x36f/0x610 fs/super.c:1615
 gfs2_get_tree+0x4e/0x280 fs/gfs2/ops_fstype.c:1322
 vfs_get_tree+0x8f/0x380 fs/super.c:1780
 do_new_mount fs/namespace.c:3352 [inline]
 path_mount+0x6e1/0x1f10 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 24:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2195 [inline]
 slab_free mm/slub.c:4436 [inline]
 kmem_cache_free+0x12f/0x3a0 mm/slub.c:4511
 i_callback+0x43/0x70 fs/inode.c:250
 rcu_do_batch kernel/rcu/tree.c:2535 [inline]
 rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2809
 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554
 run_ksoftirqd kernel/softirq.c:928 [inline]
 run_ksoftirqd+0x3a/0x60 kernel/softirq.c:920
 smpboot_thread_fn+0x661/0xa10 kernel/smpboot.c:164
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541
 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:3072
 destroy_inode+0x12c/0x1b0 fs/inode.c:316
 iput_final fs/inode.c:1741 [inline]
 iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
 iput+0x5c/0x80 fs/inode.c:1757
 gfs2_put_super+0x258/0x750 fs/gfs2/super.c:627
 generic_shutdown_super+0x159/0x3d0 fs/super.c:642
 kill_block_super+0x3b/0x90 fs/super.c:1676
 gfs2_kill_sb+0x360/0x410 fs/gfs2/ops_fstype.c:1785
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
 deactivate_super+0xde/0x100 fs/super.c:506
 cleanup_mnt+0x222/0x450 fs/namespace.c:1267
 task_work_run+0x14e/0x250 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xa9b/0x2ba0 kernel/exit.c:874
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1023
 __do_sys_exit_group kernel/exit.c:1034 [inline]
 __se_sys_exit_group kernel/exit.c:1032 [inline]
 __ia32_sys_exit_group+0x3e/0x50 kernel/exit.c:1032
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff888000ae0000
 which belongs to the cache gfs2_inode of size 1592
The buggy address is located 1208 bytes inside of
 freed 1592-byte region [ffff888000ae0000, ffff888000ae0638)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888000ae2198 pfn:0xae0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880216c5a01
flags: 0x7ff00000000040(head|node=0|zone=0|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 007ff00000000040 ffff888016f67e00 dead000000000122 0000000000000000
raw: ffff888000ae2198 0000000080130011 00000001ffffefff ffff8880216c5a01
head: 007ff00000000040 ffff888016f67e00 dead000000000122 0000000000000000
head: ffff888000ae2198 0000000080130011 00000001ffffefff ffff8880216c5a01
head: 007ff00000000003 ffffea000002b801 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
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 5361, tgid 5360 (syz-executor.0), ts 57514593072, free_ts 57494276425
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x136a/0x2df0 mm/page_alloc.c:3402
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4660
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x56/0x110 mm/slub.c:2264
 allocate_slab mm/slub.c:2427 [inline]
 new_slab+0x84/0x260 mm/slub.c:2480
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3666
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756
 __slab_alloc_node mm/slub.c:3809 [inline]
 slab_alloc_node mm/slub.c:3988 [inline]
 kmem_cache_alloc_lru_noprof+0x2a7/0x2f0 mm/slub.c:4019
 gfs2_alloc_inode+0x49/0x1f0 fs/gfs2/super.c:1537
 alloc_inode+0x5d/0x230 fs/inode.c:261
 iget5_locked fs/inode.c:1235 [inline]
 iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
 gfs2_inode_lookup+0xd1/0x8a0 fs/gfs2/inode.c:124
 gfs2_dir_search+0x22c/0x2e0 fs/gfs2/dir.c:1667
 gfs2_lookupi+0x3c5/0x6d0 fs/gfs2/inode.c:340
 gfs2_lookup_meta+0xa8/0x180 fs/gfs2/inode.c:280
 init_statfs fs/gfs2/ops_fstype.c:631 [inline]
 init_journal fs/gfs2/ops_fstype.c:797 [inline]
 init_inodes+0xf60/0x2e80 fs/gfs2/ops_fstype.c:865
page last free pid 111 tgid 111 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 free_unref_folios+0x991/0x1310 mm/page_alloc.c:2614
 shrink_folio_list+0x348a/0x4150 mm/vmscan.c:1446
 evict_folios+0x6e6/0x1bf0 mm/vmscan.c:4553
 try_to_shrink_lruvec+0x618/0x9b0 mm/vmscan.c:4749
 shrink_one+0x3f8/0x7c0 mm/vmscan.c:4788
 shrink_many mm/vmscan.c:4851 [inline]
 lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
 shrink_node mm/vmscan.c:5910 [inline]
 kswapd_shrink_node mm/vmscan.c:6720 [inline]
 balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff888000ae0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888000ae0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888000ae0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff888000ae0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888000ae0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/06 18:24 upstream 2df0193e62cf c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in do_xmote
* Struck through repros no longer work on HEAD.