RAX: dffffc0000000000 RBX: 1ffff92000020eec RCX: ffffffff94f2f903
RDX: 0000000000000001 RSI: ffffffff8c0ae240 RDI: ffffffff8c607c40
RBP: ffffc900001077f8 R08: ffffffff94f1e3ff R09: 1ffffffff29e3c7f
R10: dffffc0000000000 R11: fffffbfff29e3c80 R12: ffffffff94f1aeb8
==================================================================
BUG: KASAN: stack-out-of-bounds in __show_regs+0x23e/0x610 arch/x86/kernel/process_64.c:91
Read of size 8 at addr ffffc90000107678 by task syz.4.2251/13186
CPU: 0 UID: 0 PID: 13186 Comm: syz.4.2251 Not tainted 6.11.0-rc1-next-20240729-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
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
__show_regs+0x23e/0x610 arch/x86/kernel/process_64.c:91
show_trace_log_lvl+0x3d4/0x520 arch/x86/kernel/dumpstack.c:301
sched_show_task+0x506/0x6d0 kernel/sched/core.c:7512
report_rtnl_holders+0x327/0x400 net/core/rtnetlink.c:110
call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792
expire_timers kernel/time/timer.c:1843 [inline]
__run_timers kernel/time/timer.c:2417 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428
run_timer_base kernel/time/timer.c:2437 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447
handle_softirqs+0x2c4/0x970 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
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8a 24 ac f5 48 89 df e8 02 68 ad f5 e8 4d cb d7 f5 fb bf 01 00 00 00 62 2f 9f f5 65 8b 05 a3 25 40 74 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc90004ee65d8 EFLAGS: 00000286
RAX: ccdc786158a2c200 RBX: ffff8880207d10c0 RCX: ffffffff817022ea
RDX: dffffc0000000000 RSI: ffffffff8c0ad560 RDI: 0000000000000001
RBP: ffff88805cdf5160 R08: ffffffff937378ef R09: 1ffffffff26e6f1d
R10: dffffc0000000000 R11: fffffbfff26e6f1e R12: dffffc0000000000
R13: ffff88802081b510 R14: ffff88805cdf5160 R15: ffff88805cdf5168
spin_unlock_irq include/linux/spinlock.h:401 [inline]
loop_queue_work drivers/block/loop.c:903 [inline]
loop_queue_rq+0xa01/0xaf0 drivers/block/loop.c:1877
__blk_mq_issue_directly block/blk-mq.c:2572 [inline]
blk_mq_request_issue_directly+0x3da/0x720 block/blk-mq.c:2657
blk_mq_plug_issue_direct+0x22a/0x5c0 block/blk-mq.c:2678
blk_mq_flush_plug_list+0x842/0x1880 block/blk-mq.c:2787
__blk_flush_plug+0x420/0x500 block/blk-core.c:1198
blk_finish_plug+0x5e/0x80 block/blk-core.c:1225
ext4_mb_prefetch+0x313/0x390 fs/ext4/mballoc.c:2759
ext4_mb_regular_allocator+0xb38/0x3b80 fs/ext4/mballoc.c:2898
ext4_mb_new_blocks+0x10a8/0x4e30 fs/ext4/mballoc.c:6219
ext4_ext_map_blocks+0x1c74/0x77b0 fs/ext4/extents.c:4318
ext4_map_blocks+0xa5e/0x1d20 fs/ext4/inode.c:652
_ext4_get_block+0x239/0x6b0 fs/ext4/inode.c:794
ext4_get_block_unwritten+0x2f/0x100 fs/ext4/inode.c:827
ext4_block_write_begin+0x513/0x1800 fs/ext4/inode.c:1084
ext4_write_begin+0x629/0x10e0
ext4_da_write_begin+0x300/0xa70 fs/ext4/inode.c:2943
generic_perform_write+0x399/0x840 mm/filemap.c:4019
ext4_buffered_write_iter+0xc6/0x350 fs/ext4/file.c:299
ext4_file_write_iter+0x1de/0x1a10
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xa72/0xc90 fs/read_write.c:590
ksys_write+0x1a0/0x2c0 fs/read_write.c:643
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f34409779f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f34416e0048 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f3440b05f80 RCX: 00007f34409779f9
RDX: 0000000000000118 RSI: 00000000200001c0 RDI: 0000000000000005
RBP: 00007f34409e58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f3440b05f80 R15: 00007ffc48b5f668
The buggy address belongs to the virtual mapping at
[ffffc90000100000, ffffc90000109000) created by:
copy_process+0x5d1/0x3d90 kernel/fork.c:2206
The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x17a9d
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 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_NOWARN|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 2708963987, free_ts 0
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
prep_new_page mm/page_alloc.c:1501 [inline]
get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3442
__alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4700
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263
vm_area_alloc_pages mm/vmalloc.c:3584 [inline]
__vmalloc_area_node mm/vmalloc.c:3660 [inline]
__vmalloc_node_range_noprof+0x971/0x1460 mm/vmalloc.c:3841
alloc_thread_stack_node kernel/fork.c:314 [inline]
dup_task_struct+0x444/0x8c0 kernel/fork.c:1115
copy_process+0x5d1/0x3d90 kernel/fork.c:2206
kernel_clone+0x226/0x8f0 kernel/fork.c:2788
kernel_thread+0x1bc/0x240 kernel/fork.c:2850
create_kthread kernel/kthread.c:412 [inline]
kthreadd+0x60d/0x810 kernel/kthread.c:765
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page_owner free stack trace missing
Memory state around the buggy address:
ffffc90000107500: f2 f2 00 f2 f2 f2 00 f2 f2 f2 00 00 00 00 00 00
ffffc90000107580: f2 f2 f2 f2 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3
>ffffc90000107600: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
^
ffffc90000107680: 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00 00 00 00 00
ffffc90000107700: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2
==================================================================
----------------
Code disassembly (best guess):
0: 90 nop
1: f3 0f 1e fa endbr64
5: 53 push %rbx
6: 48 89 fb mov %rdi,%rbx
9: 48 83 c7 18 add $0x18,%rdi
d: 48 8b 74 24 08 mov 0x8(%rsp),%rsi
12: e8 8a 24 ac f5 call 0xf5ac24a1
17: 48 89 df mov %rbx,%rdi
1a: e8 02 68 ad f5 call 0xf5ad6821
1f: e8 4d cb d7 f5 call 0xf5d7cb71
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 62 2f 9f f5 call 0xf59f2f91 <-- trapping instruction
2f: 65 8b 05 a3 25 40 74 mov %gs:0x744025a3(%rip),%eax # 0x744025d9
36: 85 c0 test %eax,%eax
38: 74 06 je 0x40
3a: 5b pop %rbx
3b: c3 ret
3c: cc int3
3d: cc int3
3e: cc int3
3f: cc int3