==================================================================
BUG: KASAN: out-of-bounds in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: out-of-bounds in atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline]
BUG: KASAN: out-of-bounds in put_bh include/linux/buffer_head.h:304 [inline]
BUG: KASAN: out-of-bounds in end_buffer_read_sync+0xc3/0xe0 fs/buffer.c:161
Write of size 4 at addr ffffc90003057740 by task kworker/u8:6/1080
CPU: 0 UID: 0 PID: 1080 Comm: kworker/u8:6 Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: loop4 loop_workfn
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xb4/0x290 mm/kasan/report.c:521
kasan_report+0x118/0x150 mm/kasan/report.c:634
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x29a/0x2b0 mm/kasan/generic.c:189
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline]
put_bh include/linux/buffer_head.h:304 [inline]
end_buffer_read_sync+0xc3/0xe0 fs/buffer.c:161
end_bio_bh_io_sync+0xba/0x120 fs/buffer.c:2783
blk_update_request+0x5ee/0xe80 block/blk-mq.c:983
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1145
blk_complete_reqs block/blk-mq.c:1220 [inline]
blk_done_softirq+0x107/0x160 block/blk-mq.c:1225
handle_softirqs+0x283/0x860 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
sysvec_call_function_single+0xa1/0xc0 arch/x86/kernel/smp.c:266
asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:raise_softirq+0x162/0x200 kernel/softirq.c:741
Code: e3 40 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b 41 f7 c5 00 02 00 00 74 01 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90003c2f560 EFLAGS: 00000206
RAX: 00d3dae8234dfd00 RBX: 0000000000000004 RCX: 00d3dae8234dfd00
RDX: 0000000000000006 RSI: ffffffff8cff7ffe RDI: ffffffff8b5c3a60
RBP: ffffc90003c2f610 R08: ffffffff8eee92b7 R09: 1ffffffff1ddd256
R10: dffffc0000000000 R11: fffffbfff1ddd257 R12: 1ffff92000785eac
R13: 0000000000000a06 R14: 0000000000000004 R15: dffffc0000000000
blk_mq_raise_softirq block/blk-mq.c:1282 [inline]
blk_mq_complete_request_remote+0x51c/0x720 block/blk-mq.c:1306
blk_mq_complete_request+0x19/0xa0 block/blk-mq.c:1322
lo_rw_aio_do_completion drivers/block/loop.c:317 [inline]
lo_rw_aio_complete drivers/block/loop.c:325 [inline]
lo_rw_aio+0xda6/0xf30 drivers/block/loop.c:398
do_req_filebacked drivers/block/loop.c:-1 [inline]
loop_handle_cmd drivers/block/loop.c:1866 [inline]
loop_process_work+0x804/0xf30 drivers/block/loop.c:1901
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xa55/0x1690 kernel/workqueue.c:3319
worker_thread+0xa57/0xfc0 kernel/workqueue.c:3400
kthread+0x70e/0x890 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
The buggy address belongs to the virtual mapping at
[ffffc90003050000, ffffc90003059000) created by:
copy_process+0x544/0x3be0 kernel/fork.c:2259
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805e40bdc0 pfn:0x5e40b
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff88805e40bdc0 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 6728, tgid 6728 (syz.4.44), ts 145075257420, free_ts 145050876936
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1d0/0x220 mm/page_alloc.c:1718
prep_new_page mm/page_alloc.c:1726 [inline]
get_page_from_freelist+0x2b6b/0x2d10 mm/page_alloc.c:3688
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301
alloc_frozen_pages_noprof mm/mempolicy.c:2372 [inline]
alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2392
vm_area_alloc_pages mm/vmalloc.c:3591 [inline]
__vmalloc_area_node mm/vmalloc.c:3669 [inline]
__vmalloc_node_range_noprof+0x8fe/0x12b0 mm/vmalloc.c:3844
__vmalloc_node_noprof+0x7d/0x90 mm/vmalloc.c:3907
alloc_thread_stack_node kernel/fork.c:314 [inline]
dup_task_struct+0x3e7/0x860 kernel/fork.c:1136
copy_process+0x544/0x3be0 kernel/fork.c:2259
kernel_clone+0x224/0x7f0 kernel/fork.c:2844
__do_sys_clone3 kernel/fork.c:3148 [inline]
__se_sys_clone3+0x256/0x2d0 kernel/fork.c:3127
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x7f/0x160 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
page last free pid 22 tgid 22 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1262 [inline]
__free_frozen_pages+0xafe/0xcb0 mm/page_alloc.c:2725
rcu_do_batch kernel/rcu/tree.c:2568 [inline]
rcu_core+0xc99/0x16f0 kernel/rcu/tree.c:2824
handle_softirqs+0x283/0x860 kernel/softirq.c:579
run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164
kthread+0x70e/0x890 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffffc90003057600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffc90003057680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90003057700: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 00 00 00 f2
^
ffffc90003057780: f2 f2 f2 f2 00 f2 f2 f2 01 f3 f3 f3 00 00 00 00
ffffc90003057800: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
==================================================================
----------------
Code disassembly (best guess):
0: e3 40 jrcxz 0x42
2: 00 48 c7 add %cl,-0x39(%rax)
5: 44 24 20 rex.R and $0x20,%al
8: 00 00 add %al,(%rax)
a: 00 00 add %al,(%rax)
c: 9c pushf
d: 8f 44 24 20 pop 0x20(%rsp)
11: f6 44 24 21 02 testb $0x2,0x21(%rsp)
16: 75 4b jne 0x63
18: 41 f7 c5 00 02 00 00 test $0x200,%r13d
1f: 74 01 je 0x22
21: fb sti
22: 48 c7 04 24 0e 36 e0 movq $0x45e0360e,(%rsp)
29: 45
* 2a: 4b c7 04 3c 00 00 00 movq $0x0,(%r12,%r15,1) <-- trapping instruction
31: 00
32: 66 43 c7 44 3c 09 00 movw $0x0,0x9(%r12,%r15,1)
39: 00
3a: 43 c6 44 3c 0b 00 movb $0x0,0xb(%r12,%r15,1)