syzbot


KASAN: use-after-free Read in relay_switch_subbuf

Status: auto-obsoleted due to no activity on 2023/08/23 09:04
Reported-by: syzbot+148f4a3e4d77faf4c927@syzkaller.appspotmail.com
First crash: 325d, last: 305d
Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in relay_switch_subbuf block trace C done error 93 492d 1986d 0/26 auto-obsoleted due to no activity on 2023/04/20 06:56
linux-4.19 KASAN: use-after-free Read in relay_switch_subbuf 10 1347d 1771d 0/1 auto-closed as invalid on 2020/10/24 01:02
linux-4.14 KASAN: use-after-free Read in relay_switch_subbuf C done unreliable 5 538d 1580d 0/1 upstream: reported C repro on 2019/11/05 17:36
linux-4.19 KASAN: use-after-free Read in relay_switch_subbuf (2) 23 385d 868d 0/1 upstream: reported on 2021/10/17 18:33
linux-5.15 KASAN: use-after-free Read in relay_switch_subbuf (2) 1 147d 147d 0/3 auto-obsoleted due to no activity on 2024/01/17 02:38
linux-4.14 general protection fault in relay_switch_subbuf 2 1438d 1531d 0/1 auto-closed as invalid on 2020/07/25 03:12
upstream general protection fault in relay_switch_subbuf block trace 4 1865d 1837d 0/26 auto-closed as invalid on 2019/07/23 22:29
upstream general protection fault in relay_switch_subbuf (2) block trace 1 1678d 1669d 0/26 auto-closed as invalid on 2019/10/25 14:11
upstream general protection fault in relay_switch_subbuf (3) block trace 1 1585d 1585d 0/26 auto-closed as invalid on 2020/01/29 10:20
linux-4.19 general protection fault in relay_switch_subbuf 1 1661d 1661d 0/1 auto-closed as invalid on 2019/12/15 08:14
linux-4.19 general protection fault in relay_switch_subbuf (2) 1 1358d 1358d 0/1 auto-closed as invalid on 2020/10/13 07:52

Sample crash report:
loop1: detected capacity change from 0 to 40427
==================================================================
BUG: KASAN: use-after-free in d_inode include/linux/dcache.h:526 [inline]
BUG: KASAN: use-after-free in relay_switch_subbuf+0x285/0x6e0 kernel/relay.c:676
Read of size 8 at addr ffff8880771e2f18 by task syz-executor.1/32479

CPU: 0 PID: 32479 Comm: syz-executor.1 Not tainted 5.15.107-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 d_inode include/linux/dcache.h:526 [inline]
 relay_switch_subbuf+0x285/0x6e0 kernel/relay.c:676
 relay_reserve include/linux/relay.h:248 [inline]
 trace_note+0x553/0x6f0 kernel/trace/blktrace.c:95
 trace_note_tsk+0xa9/0x140 kernel/trace/blktrace.c:126
 __blk_add_trace+0x9f5/0xd70 kernel/trace/blktrace.c:267
 blk_add_trace_bio+0x280/0x2d0 kernel/trace/blktrace.c:905
 trace_block_bio_queue include/trace/events/block.h:332 [inline]
 submit_bio_checks+0x182c/0x1920 block/blk-core.c:893
 __submit_bio+0x5a1/0x850 block/blk-core.c:917
 __submit_bio_noacct_mq block/blk-core.c:1003 [inline]
 submit_bio_noacct+0x955/0xb30 block/blk-core.c:1033
 submit_bio+0x2dd/0x560 block/blk-core.c:1095
 submit_bh fs/buffer.c:3062 [inline]
 __bread_slow fs/buffer.c:1180 [inline]
 __bread_gfp+0x1c2/0x390 fs/buffer.c:1384
 sb_bread include/linux/buffer_head.h:337 [inline]
 read_raw_super_block fs/f2fs/super.c:3730 [inline]
 f2fs_fill_super+0x474/0x8350 fs/f2fs/super.c:3993
 mount_bdev+0x26d/0x3a0 fs/super.c:1378
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:610
 vfs_get_tree+0x88/0x270 fs/super.c:1508
 do_new_mount+0x28b/0xad0 fs/namespace.c:2994
 do_mount fs/namespace.c:3337 [inline]
 __do_sys_mount fs/namespace.c:3545 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3522
 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+0x61/0xcb
RIP: 0033:0x7f65a67d969a
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 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:00007f65a4d49f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000000054e6 RCX: 00007f65a67d969a
RDX: 0000000020000040 RSI: 0000000020000080 RDI: 00007f65a4d49fe0
RBP: 00007f65a4d4a020 R08: 00007f65a4d4a020 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000040
R13: 0000000020000080 R14: 00007f65a4d49fe0 R15: 0000000020000000
 </TASK>

Allocated by task 32306:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 __d_alloc+0x2a/0x700 fs/dcache.c:1744
 d_alloc+0x48/0x1d0 fs/dcache.c:1823
 __lookup_hash+0xca/0x240 fs/namei.c:1556
 filename_create+0x28d/0x530 fs/namei.c:3766
 do_symlinkat+0xf6/0x600 fs/namei.c:4377
 __do_sys_symlinkat fs/namei.c:4404 [inline]
 __se_sys_symlinkat fs/namei.c:4401 [inline]
 __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4401
 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+0x61/0xcb

Freed by task 32454:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
 rcu_do_batch kernel/rcu/tree.c:2509 [inline]
 rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2749
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2993 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3073
 __dentry_kill+0x4f4/0x650 fs/dcache.c:596
 shrink_dentry_list+0x398/0x6a0 fs/dcache.c:1176
 shrink_dcache_parent+0xc9/0x480
 vfs_rmdir+0x34e/0x460 fs/namei.c:4082
 do_rmdir+0x362/0x670 fs/namei.c:4139
 __do_sys_unlinkat fs/namei.c:4319 [inline]
 __se_sys_unlinkat fs/namei.c:4313 [inline]
 __x64_sys_unlinkat+0xdc/0xf0 fs/namei.c:4313
 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+0x61/0xcb

Second to last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2993 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3073
 __dentry_kill+0x4f4/0x650 fs/dcache.c:596
 shrink_dentry_list+0x398/0x6a0 fs/dcache.c:1176
 shrink_dcache_parent+0xc9/0x480
 vfs_rmdir+0x34e/0x460 fs/namei.c:4082
 do_rmdir+0x362/0x670 fs/namei.c:4139
 __do_sys_unlinkat fs/namei.c:4319 [inline]
 __se_sys_unlinkat fs/namei.c:4313 [inline]
 __x64_sys_unlinkat+0xdc/0xf0 fs/namei.c:4313
 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+0x61/0xcb

The buggy address belongs to the object at ffff8880771e2eb0
 which belongs to the cache dentry of size 312
The buggy address is located 104 bytes inside of
 312-byte region [ffff8880771e2eb0, ffff8880771e2fe8)
The buggy address belongs to the page:
page:ffffea0001dc7880 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880771e2758 pfn:0x771e2
head:ffffea0001dc7880 order:1 compound_mapcount:0
memcg:ffff888052589301
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000060e108 ffffea00013cac88 ffff888011dc6640
raw: ffff8880771e2758 000000000015000f 00000001ffffffff ffff888052589301
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 2972, ts 14810431321, free_ts 11248807290
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x18e/0x280 mm/slub.c:3233
 __d_alloc+0x2a/0x700 fs/dcache.c:1744
 d_alloc fs/dcache.c:1823 [inline]
 d_alloc_parallel+0xca/0x1390 fs/dcache.c:2575
 __lookup_slow+0x111/0x3d0 fs/namei.c:1644
 lookup_slow+0x53/0x70 fs/namei.c:1676
 walk_component+0x48c/0x610 fs/namei.c:1972
 link_path_walk+0x642/0xd90
 path_lookupat+0xa9/0x450 fs/namei.c:2450
 filename_lookup+0x230/0x5c0 fs/namei.c:2480
 user_path_at_empty+0x40/0x180 fs/namei.c:2853
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x106/0x3b0 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_contig_range+0x95/0xf0 mm/page_alloc.c:9321
 destroy_args+0xfe/0x97f mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x40d/0x462 mm/debug_vm_pgtable.c:1331
 do_one_initcall+0x22b/0x7a0 init/main.c:1306
 do_initcall_level+0x157/0x207 init/main.c:1379
 do_initcalls+0x49/0x86 init/main.c:1395
 kernel_init_freeable+0x43c/0x5c5 init/main.c:1619
 kernel_init+0x19/0x290 init/main.c:1510
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Memory state around the buggy address:
 ffff8880771e2e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
 ffff8880771e2e80: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb
>ffff8880771e2f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880771e2f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff8880771e3000: fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/13 19:02 linux-5.15.y 4fdad925aa1a 3cfcaa1b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in relay_switch_subbuf
2023/05/03 22:23 linux-5.15.y 8a7f2a5c5aa1 b5918830 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in relay_switch_subbuf
* Struck through repros no longer work on HEAD.