syzbot


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

Status: fixed on 2023/07/01 16:05
Subsystems: nilfs
[Documentation on labels]
Reported-by: syzbot+78d4495558999f55d1da@syzkaller.appspotmail.com
Fix commit: 9b5a04ac3ad9 nilfs2: fix use-after-free bug of nilfs_root in nilfs_evict_inode()
First crash: 376d, last: 323d
Cause bisection: failed (error log, bisect log)
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] nilfs2: fix use-after-free bug of nilfs_root in nilfs_evict_inode() 3 (3) 2023/05/12 23:46
[syzbot] [nilfs?] KASAN: slab-use-after-free Read in nilfs_load_inode_block 0 (1) 2023/05/07 15:32
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in nilfs_load_inode_block (2) nilfs C done 4 286d 300d 23/26 fixed on 2023/10/12 12:48
upstream KASAN: use-after-free Read in nilfs_load_inode_block nilfs 1 586d 586d 0/26 closed as dup on 2022/10/11 10:33

Sample crash report:
NILFS (loop2): error -5 truncating bmap (ino=15)
==================================================================
BUG: KASAN: slab-use-after-free in nilfs_load_inode_block+0x11e/0x280 fs/nilfs2/inode.c:1012
Read of size 8 at addr ffff88801f47f430 by task syz-executor323/4999

CPU: 0 PID: 4999 Comm: syz-executor323 Not tainted 6.3.0-syzkaller-13466-gfc4354c6e5c2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 nilfs_load_inode_block+0x11e/0x280 fs/nilfs2/inode.c:1012
 __nilfs_mark_inode_dirty+0xa5/0x280 fs/nilfs2/inode.c:1089
 nilfs_mark_inode_dirty fs/nilfs2/nilfs.h:288 [inline]
 nilfs_evict_inode+0x189/0x420 fs/nilfs2/inode.c:934
 evict+0x2a4/0x620 fs/inode.c:665
 nilfs_dispose_list+0x51d/0x5c0 fs/nilfs2/segment.c:816
 nilfs_detach_log_writer+0xaf1/0xbb0 fs/nilfs2/segment.c:2852
 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:477
 generic_shutdown_super+0x134/0x340 fs/super.c:500
 kill_block_super+0x84/0xf0 fs/super.c:1407
 deactivate_locked_super+0xa4/0x110 fs/super.c:331
 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1177
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 ptrace_notify+0x2cd/0x380 kernel/signal.c:2369
 ptrace_report_syscall include/linux/ptrace.h:411 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
 syscall_exit_work kernel/entry/common.c:252 [inline]
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:279 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline]
 syscall_exit_to_user_mode+0x157/0x280 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0b39ccba87
Code: ff d0 48 89 c7 b8 3c 00 00 00 0f 05 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 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:00007ffcfc3da598 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f0b39ccba87
RDX: 00007ffcfc3da659 RSI: 000000000000000a RDI: 00007ffcfc3da650
RBP: 00007ffcfc3da650 R08: 00000000ffffffff R09: 00007ffcfc3da430
R10: 00005555563da683 R11: 0000000000000202 R12: 00007ffcfc3db710
R13: 00005555563da5f0 R14: 00007ffcfc3da5c0 R15: 00007ffcfc3db730
 </TASK>

Allocated by task 5216:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 nilfs_find_or_create_root+0x137/0x4e0 fs/nilfs2/the_nilfs.c:810
 nilfs_attach_checkpoint+0x123/0x4d0 fs/nilfs2/super.c:529
 nilfs_fill_super+0x321/0x600 fs/nilfs2/super.c:1074
 nilfs_mount+0x67d/0x9a0 fs/nilfs2/super.c:1326
 legacy_get_tree+0xef/0x190 fs/fs_context.c:610
 vfs_get_tree+0x8c/0x270 fs/super.c:1510
 do_new_mount+0x28f/0xae0 fs/namespace.c:3039
 do_mount fs/namespace.c:3382 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 4999:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3786 [inline]
 __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799
 nilfs_segctor_destroy fs/nilfs2/segment.c:2775 [inline]
 nilfs_detach_log_writer+0x8c1/0xbb0 fs/nilfs2/segment.c:2838
 nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:477
 generic_shutdown_super+0x134/0x340 fs/super.c:500
 kill_block_super+0x84/0xf0 fs/super.c:1407
 deactivate_locked_super+0xa4/0x110 fs/super.c:331
 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1177
 task_work_run+0x24a/0x300 kernel/task_work.c:179
 ptrace_notify+0x2cd/0x380 kernel/signal.c:2369
 ptrace_report_syscall include/linux/ptrace.h:411 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
 syscall_exit_work kernel/entry/common.c:252 [inline]
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:279 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline]
 syscall_exit_to_user_mode+0x157/0x280 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88801f47f400
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 48 bytes inside of
 freed 256-byte region [ffff88801f47f400, ffff88801f47f500)

The buggy address belongs to the physical page:
page:ffffea00007d1f80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801f47f600 pfn:0x1f47e
head:ffffea00007d1f80 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000010200 ffff888012441b40 ffffea00008ccc90 ffffea00007a7510
raw: ffff88801f47f600 000000000010000e 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 9284804112, free_ts 0
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768
 alloc_page_interleave+0x22/0x1d0 mm/mempolicy.c:2112
 alloc_slab_page+0x6a/0x160 mm/slub.c:1851
 allocate_slab mm/slub.c:1998 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1057
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 bus_add_driver+0x163/0x620 drivers/base/bus.c:657
 driver_register+0x23a/0x320 drivers/base/driver.c:246
 do_one_initcall+0x23d/0x7d0 init/main.c:1246
 do_initcall_level+0x157/0x210 init/main.c:1319
 do_initcalls+0x3f/0x80 init/main.c:1335
 kernel_init_freeable+0x43b/0x5d0 init/main.c:1571
 kernel_init+0x1d/0x2a0 init/main.c:1462
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88801f47f300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801f47f380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801f47f400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88801f47f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801f47f500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/07 12:38 upstream fc4354c6e5c2 90c93c40 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/29 15:01 upstream b19edac5992d 134ddc02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/23 01:21 upstream dad9774deaf1 79782afc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/21 18:28 upstream e660abd551f1 79782afc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/14 17:06 upstream b6dad5178cea d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/10 22:46 upstream 64569520920a 49519f06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/06 07:31 upstream f8dba31b0a82 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/24 01:35 upstream ae8373a5add4 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/21 07:46 upstream 0dd2a6fb1e34 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/14 16:13 upstream bb7c241fae62 2b9ba477 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/12 08:35 upstream 105131df9c3b adb9a3cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/10 16:26 upstream 16a8829130ca 14b12a99 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/09 21:03 upstream 1dc3731daf1f 30aa2a7e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/08 17:32 upstream ac9a78681b92 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/07 11:40 upstream fc4354c6e5c2 90c93c40 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/05 13:10 linux-next 715abedee4cd a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/06/04 17:35 linux-next 715abedee4cd a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in nilfs_load_inode_block
2023/05/23 05:47 linux-next 715abedee4cd 4bce1a3e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in nilfs_load_inode_block
* Struck through repros no longer work on HEAD.