[syzbot] [mm?] KASAN: slab-use-after-free Read in lru_add_fn

syzbot
2024-05-09T05:58:26Z

Hello,

syzbot found the following issue on:

HEAD commit: 9221b2819b8a Add linux-next specific files for 20240503
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1263897f180000
kernel config: https://syzkaller.appspot.com/x/.config?x=8ab537f51a6a0d98
dashboard link: https://syzkaller.appspot.com/bug?extid=d79afb004be235636ee8
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17d47450980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3e67dbdc3c37/disk-9221b281.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ade618fa19f8/vmlinux-9221b281.xz
kernel image: https://storage.googleapis.com/syzbot-assets/df12e5073c97/bzImage-9221b281.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/98f66c028d40/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d79afb004be235636ee8@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline]
BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: slab-use-after-free in mapping_unevictable include/linux/pagemap.h:257 [inline]
BUG: KASAN: slab-use-after-free in folio_evictable mm/internal.h:353 [inline]
BUG: KASAN: slab-use-after-free in lru_add_fn+0x2cc/0x1a20 mm/swap.c:184
Read of size 8 at addr ffff88807ffa84a8 by task udevd/5139

CPU: 0 PID: 5139 Comm: udevd Not tainted 6.9.0-rc6-next-20240503-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:68 [inline]
_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
mapping_unevictable include/linux/pagemap.h:257 [inline]
folio_evictable mm/internal.h:353 [inline]
lru_add_fn+0x2cc/0x1a20 mm/swap.c:184
folio_batch_move_lru+0x322/0x690 mm/swap.c:220
lru_add_drain_cpu+0x10e/0x8c0 mm/swap.c:657
lru_add_drain+0x123/0x3e0 mm/swap.c:757
wp_can_reuse_anon_folio mm/memory.c:3550 [inline]
do_wp_page+0x2c65/0x5310 mm/memory.c:3662
handle_pte_fault+0x1189/0x70f0 mm/memory.c:5396
__handle_mm_fault mm/memory.c:5523 [inline]
handle_mm_fault+0x10df/0x1ba0 mm/memory.c:5688
do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
handle_page_fault arch/x86/mm/fault.c:1481 [inline]
exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fe7b90c72a4
Code: c0 02 49 8b 0c c6 64 8b 34 25 18 00 00 00 85 f6 75 22 48 39 cd 75 0c 48 8d 3d 24 e6 0e 00 e9 66 fe ff ff 48 c1 ea 0c 48 31 ca <48> 89 55 10 49 89 2c c6 eb 3c 89 d8 48 c1 ea 0c 48 89 ce 49 8d 3c
RSP: 002b:00007ffc001e7800 EFLAGS: 00010206
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 000055697463f110
RDX: 0000556c22f4b72b RSI: 0000000000000000 RDI: 000055697463b660
RBP: 000055697463b650 R08: 0000000000000007 R09: 729c72b1ba2b10a4
R10: f6f0f8c87f29ff62 R11: 0000000000000007 R12: 0000000000000000
R13: 000055697463b680 R14: 00007fe7b91f1aa0 R15: 0000556974631910
</TASK>

Allocated by task 5122:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:312 [inline]
__kasan_slab_alloc+0x66/0x80 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+0x139/0x2b0 mm/slub.c:4019
nilfs_alloc_inode+0x2e/0xf0 fs/nilfs2/super.c:154
alloc_inode fs/inode.c:261 [inline]
iget5_locked+0xa4/0x280 fs/inode.c:1235
nilfs_iget_locked+0x12b/0x180 fs/nilfs2/inode.c:606
nilfs_ifile_read+0x30/0x1b0 fs/nilfs2/ifile.c:192
nilfs_attach_checkpoint+0xed/0x1a0 fs/nilfs2/super.c:557
nilfs_fill_super+0x380/0x6a0 fs/nilfs2/super.c:1067
nilfs_get_tree+0x4f9/0x920 fs/nilfs2/super.c:1211
vfs_get_tree+0x90/0x2a0 fs/super.c:1780
do_new_mount+0x2be/0xb40 fs/namespace.c:3352
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 0:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
__kasan_slab_free+0x37/0x60 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+0x145/0x350 mm/slub.c:4511
rcu_do_batch kernel/rcu/tree.c:2566 [inline]
rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2840
handle_softirqs+0x2d6/0x990 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
__kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
__call_rcu_common kernel/rcu/tree.c:3103 [inline]
call_rcu+0x167/0xa70 kernel/rcu/tree.c:3207
nilfs_put_root+0x97/0xc0 fs/nilfs2/the_nilfs.c:909
nilfs_segctor_destroy fs/nilfs2/segment.c:2753 [inline]
nilfs_detach_log_writer+0x8bb/0xbe0 fs/nilfs2/segment.c:2816
nilfs_put_super+0x4d/0x160 fs/nilfs2/super.c:498
generic_shutdown_super+0x136/0x2d0 fs/super.c:642
kill_block_super+0x44/0x90 fs/super.c:1676
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267
task_work_run+0x24f/0x310 kernel/task_work.c:180
ptrace_notify+0x2d2/0x380 kernel/signal.c:2402
ptrace_report_syscall include/linux/ptrace.h:415 [inline]
ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
syscall_exit_work+0xc6/0x190 kernel/entry/common.c:173
syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
syscall_exit_to_user_mode+0x273/0x370 kernel/entry/common.c:218
do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807ffa8000
which belongs to the cache nilfs2_inode_cache of size 1512
The buggy address is located 1192 bytes inside of
freed 1512-byte region [ffff88807ffa8000, ffff88807ffa85e8)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7ffa8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88801f030301
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 00fff00000000040 ffff88801abec3c0 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080130013 00000001ffffefff ffff88801f030301
head: 00fff00000000040 ffff88801abec3c0 dead000000000122 0000000000000000
head: 0000000000000000 0000000080130013 00000001ffffefff ffff88801f030301
head: 00fff00000000003 ffffea0001ffea01 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 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 5122, tgid 5122 (syz-executor.0), ts 74532588239, free_ts 16451630334
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
prep_new_page mm/page_alloc.c:1476 [inline]
get_page_from_freelist+0x2ce2/0x2d90 mm/page_alloc.c:3438
__alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4696
__alloc_pages_node_noprof include/linux/gfp.h:244 [inline]
alloc_pages_node_noprof include/linux/gfp.h:271 [inline]
alloc_slab_page+0x5f/0x120 mm/slub.c:2264
allocate_slab+0x5a/0x2e0 mm/slub.c:2427
new_slab mm/slub.c:2480 [inline]
___slab_alloc+0xcd1/0x14b0 mm/slub.c:3666
__slab_alloc+0x58/0xa0 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+0x1c5/0x2b0 mm/slub.c:4019
nilfs_alloc_inode+0x2e/0xf0 fs/nilfs2/super.c:154
alloc_inode fs/inode.c:261 [inline]
iget5_locked+0xa4/0x280 fs/inode.c:1235
nilfs_iget_locked+0x12b/0x180 fs/nilfs2/inode.c:606
nilfs_ifile_read+0x30/0x1b0 fs/nilfs2/ifile.c:192
nilfs_attach_checkpoint+0xed/0x1a0 fs/nilfs2/super.c:557
nilfs_fill_super+0x380/0x6a0 fs/nilfs2/super.c:1067
nilfs_get_tree+0x4f9/0x920 fs/nilfs2/super.c:1211
vfs_get_tree+0x90/0x2a0 fs/super.c:1780
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1088 [inline]
free_unref_page+0xd22/0xea0 mm/page_alloc.c:2601
free_contig_range+0x9e/0x160 mm/page_alloc.c:6655
destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1037
debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1417
do_one_initcall+0x248/0x880 init/main.c:1265
do_initcall_level+0x157/0x210 init/main.c:1327
do_initcalls+0x3f/0x80 init/main.c:1343
kernel_init_freeable+0x435/0x5d0 init/main.c:1576
kernel_init+0x1d/0x2b0 init/main.c:1465
ret_from_fork+0x4b/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:
ffff88807ffa8380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807ffa8400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ffa8480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807ffa8500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807ffa8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
==================================================================

---
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