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KASAN: use-after-free Read in __shrink_extent_tree

Status: auto-obsoleted due to no activity on 2023/06/04 08:00
Subsystems: f2fs
[Documentation on labels]
Reported-by: syzbot+552d3bff86d241487b03@syzkaller.appspotmail.com
First crash: 483d, last: 475d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [f2fs?] KASAN: use-after-free Read in __shrink_extent_tree 0 (1) 2023/01/31 13:48

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:72 [inline]
BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in queued_write_trylock include/asm-generic/qrwlock.h:67 [inline]
BUG: KASAN: use-after-free in do_raw_write_trylock+0x6e/0x1f0 kernel/locking/spinlock_debug.c:216
Read of size 4 at addr ffff8880276cd510 by task syz-executor.1/5105

CPU: 0 PID: 5105 Comm: syz-executor.1 Not tainted 6.2.0-rc5-syzkaller-00047-g7c46948a6e9c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x290 lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:306
 print_report+0x107/0x1f0 mm/kasan/report.c:417
 kasan_report+0xcd/0x100 mm/kasan/report.c:517
 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
 queued_write_trylock include/asm-generic/qrwlock.h:67 [inline]
 do_raw_write_trylock+0x6e/0x1f0 kernel/locking/spinlock_debug.c:216
 __raw_write_trylock include/linux/rwlock_api_smp.h:132 [inline]
 _raw_write_trylock+0x1c/0x70 kernel/locking/spinlock.c:292
 __shrink_extent_tree+0x85d/0xc50 fs/f2fs/extent_cache.c:1015
 f2fs_leave_shrinker+0x80/0x250 fs/f2fs/shrinker.c:142
 f2fs_put_super+0x59b/0xc20 fs/f2fs/super.c:1597
 generic_shutdown_super+0x130/0x310 fs/super.c:492
 kill_block_super+0x79/0xd0 fs/super.c:1386
 kill_f2fs_super+0x2f9/0x3c0 fs/f2fs/super.c:4640
 deactivate_locked_super+0xa7/0xf0 fs/super.c:332
 cleanup_mnt+0x494/0x520 fs/namespace.c:1291
 task_work_run+0x243/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x124/0x150 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xb2/0x140 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x26/0x60 kernel/entry/common.c:296
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f779e88d537
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff5ea91f98 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f779e88d537
RDX: 00007fff5ea9206a RSI: 000000000000000a RDI: 00007fff5ea92060
RBP: 00007fff5ea92060 R08: 00000000ffffffff R09: 00007fff5ea91e30
R10: 0000555555e448b3 R11: 0000000000000246 R12: 00007f779e8e6b24
R13: 00007fff5ea93120 R14: 0000555555e44810 R15: 00007fff5ea93160
 </TASK>

Allocated by task 9209:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:325
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:761 [inline]
 slab_alloc_node mm/slub.c:3452 [inline]
 slab_alloc mm/slub.c:3460 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3467 [inline]
 kmem_cache_alloc+0x1b3/0x350 mm/slub.c:3476
 f2fs_kmem_cache_alloc_nofail fs/f2fs/f2fs.h:2796 [inline]
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2806 [inline]
 __grab_extent_tree+0x19b/0x420 fs/f2fs/extent_cache.c:423
 f2fs_init_extent_tree+0x20c/0x450 fs/f2fs/extent_cache.c:533
 f2fs_new_inode+0xd89/0x1060 fs/f2fs/namei.c:312
 __f2fs_tmpfile+0xa5/0x380 fs/f2fs/namei.c:852
 f2fs_ioc_start_atomic_write+0x3ec/0x970 fs/f2fs/file.c:2098
 __f2fs_ioctl+0x137d/0xb540
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 9242:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:518
 ____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:1781 [inline]
 slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1807
 slab_free mm/slub.c:3787 [inline]
 kmem_cache_free+0x94/0x1d0 mm/slub.c:3809
 __destroy_extent_tree+0x6fa/0x880 fs/f2fs/extent_cache.c:1193
 f2fs_destroy_extent_tree+0x13/0x20 fs/f2fs/extent_cache.c:1204
 f2fs_evict_inode+0x324/0x1310 fs/f2fs/inode.c:789
 evict+0x2a4/0x620 fs/inode.c:664
 f2fs_abort_atomic_write+0xc7/0x410 fs/f2fs/segment.c:196
 f2fs_ioc_abort_atomic_write fs/f2fs/file.c:2182 [inline]
 __f2fs_ioctl+0x3294/0xb540 fs/f2fs/file.c:4156
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff8880276cd4e0
 which belongs to the cache f2fs_extent_tree of size 144
The buggy address is located 48 bytes inside of
 144-byte region [ffff8880276cd4e0, ffff8880276cd570)

The buggy address belongs to the physical page:
page:ffffea00009db340 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880276cd820 pfn:0x276cd
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffff8880193cab40 dead000000000122 0000000000000000
raw: ffff8880276cd820 000000008013000b 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x112c50(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 6721, tgid 6674 (syz-executor.5), ts 321161536352, free_ts 299722486648
 prep_new_page mm/page_alloc.c:2531 [inline]
 get_page_from_freelist+0x742/0x7c0 mm/page_alloc.c:4283
 __alloc_pages+0x259/0x560 mm/page_alloc.c:5549
 alloc_slab_page+0xbd/0x190 mm/slub.c:1851
 allocate_slab+0x5e/0x3c0 mm/slub.c:1998
 new_slab mm/slub.c:2051 [inline]
 ___slab_alloc+0x782/0xe20 mm/slub.c:3193
 __slab_alloc mm/slub.c:3292 [inline]
 __slab_alloc_node mm/slub.c:3345 [inline]
 slab_alloc_node mm/slub.c:3442 [inline]
 slab_alloc mm/slub.c:3460 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3467 [inline]
 kmem_cache_alloc+0x268/0x350 mm/slub.c:3476
 f2fs_kmem_cache_alloc_nofail fs/f2fs/f2fs.h:2796 [inline]
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2806 [inline]
 __grab_extent_tree+0x19b/0x420 fs/f2fs/extent_cache.c:423
 f2fs_init_extent_tree+0x20c/0x450 fs/f2fs/extent_cache.c:533
 f2fs_new_inode+0xd89/0x1060 fs/f2fs/namei.c:312
 __f2fs_tmpfile+0xa5/0x380 fs/f2fs/namei.c:852
 f2fs_ioc_start_atomic_write+0x3ec/0x970 fs/f2fs/file.c:2098
 __f2fs_ioctl+0x137d/0xb540
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1446 [inline]
 free_pcp_prepare+0x751/0x780 mm/page_alloc.c:1496
 free_unref_page_prepare mm/page_alloc.c:3369 [inline]
 free_unref_page+0x19/0x4c0 mm/page_alloc.c:3464
 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:302
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:761 [inline]
 slab_alloc_node mm/slub.c:3452 [inline]
 __kmem_cache_alloc_node+0x1e0/0x340 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:967 [inline]
 __kmalloc+0x9e/0x190 mm/slab_common.c:981
 kmalloc include/linux/slab.h:584 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80
 tomoyo_path_perm+0x344/0x670 security/tomoyo/file.c:831
 tomoyo_path_symlink+0xda/0x110 security/tomoyo/tomoyo.c:211
 security_path_symlink+0xd6/0x160 security/security.c:1212
 do_symlinkat+0x11b/0x5f0 fs/namei.c:4425
 __do_sys_symlinkat fs/namei.c:4447 [inline]
 __se_sys_symlinkat fs/namei.c:4444 [inline]
 __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4444
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff8880276cd400: fc fc fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880276cd480: fb fb fb fb fc fc fc fc fc fc fc fc fa fb fb fb
>ffff8880276cd500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
                         ^
 ffff8880276cd580: fc fc fc fc fc fc fb fb fb fb fb fb fb fb fb fb
 ffff8880276cd600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/27 13:39 upstream 7c46948a6e9c 9dfcf09c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in __shrink_extent_tree
2023/02/04 08:00 upstream 0136d86b7852 1b2f701a .config console log report info ci-qemu-upstream-386 KASAN: use-after-free Read in __shrink_extent_tree
* Struck through repros no longer work on HEAD.