==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_write include/linux/instrumented.h:82 [inline]
BUG: KASAN: slab-use-after-free in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
BUG: KASAN: slab-use-after-free in cpumask_clear_cpu include/linux/cpumask.h:628 [inline]
BUG: KASAN: slab-use-after-free in flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132
Write of size 8 at addr ffff888028ade000 by task syz.7.1038/11338
CPU: 0 UID: 0 PID: 11338 Comm: syz.7.1038 Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xd2/0x2b0 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+0x2b0/0x2c0 mm/kasan/generic.c:189
instrument_atomic_write include/linux/instrumented.h:82 [inline]
clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
cpumask_clear_cpu include/linux/cpumask.h:628 [inline]
flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132
csd_do_func kernel/smp.c:134 [inline]
__flush_smp_call_function_queue+0x370/0xaa0 kernel/smp.c:540
__sysvec_call_function_single+0xa8/0x3d0 arch/x86/kernel/smp.c:271
instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
sysvec_call_function_single+0x9e/0xc0 arch/x86/kernel/smp.c:266
asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:console_flush_all+0x7f7/0xc40 kernel/printk/printk.c:3227
Code: 48 21 c3 0f 85 e9 01 00 00 e8 b5 36 1f 00 48 8b 5c 24 20 4d 85 f6 75 07 e8 a6 36 1f 00 eb 06 e8 9f 36 1f 00 fb 48 8b 44 24 28 <42> 80 3c 20 00 74 08 48 89 df e8 0a 4a 83 00 48 8b 1b 48 8b 44 24
RSP: 0018:ffffc9000429f120 EFLAGS: 00000283
RAX: 1ffffffff1d36b7b RBX: ffffffff8e9b5bd8 RCX: 0000000000080000
RDX: ffffc900134a0000 RSI: 000000000000266a RDI: 000000000000266b
RBP: ffffc9000429f270 R08: ffffffff8fa17c37 R09: 1ffffffff1f42f86
R10: dffffc0000000000 R11: fffffbfff1f42f87 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000200 R15: ffffffff8e9b5b80
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
random_pm_notification+0x1ba/0x1f0 drivers/char/random.c:856
notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
notifier_call_chain_robust kernel/notifier.c:120 [inline]
blocking_notifier_call_chain_robust+0x85/0x100 kernel/notifier.c:345
pm_notifier_call_chain_robust+0x2c/0x60 kernel/power/main.c:102
snapshot_open+0x133/0x280 kernel/power/user.c:87
misc_open+0x2b9/0x330 drivers/char/misc.c:161
chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
do_dentry_open+0xdf0/0x1970 fs/open.c:964
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1434
do_sys_open fs/open.c:1449 [inline]
__do_sys_openat fs/open.c:1465 [inline]
__se_sys_openat fs/open.c:1460 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1460
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdf5cd8e929
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:00007fdf5dbc9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fdf5cfb6080 RCX: 00007fdf5cd8e929
RDX: 00000000000c2d41 RSI: 00002000000000c0 RDI: ffffffffffffff9c
RBP: 00007fdf5ce10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdf5cfb6080 R15: 00007ffe51363708
Allocated by task 10032:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
dup_mm kernel/fork.c:1466 [inline]
copy_mm+0xdb/0x4b0 kernel/fork.c:1528
copy_process+0x1706/0x3c00 kernel/fork.c:2168
kernel_clone+0x21e/0x870 kernel/fork.c:2598
__do_sys_clone kernel/fork.c:2741 [inline]
__se_sys_clone kernel/fork.c:2725 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 11335:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4782
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x2300 kernel/exit.c:947
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
__do_sys_exit_group kernel/exit.c:1111 [inline]
__se_sys_exit_group kernel/exit.c:1109 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888028add600
which belongs to the cache mm_struct of size 2584
The buggy address is located 2560 bytes inside of
freed 2584-byte region [ffff888028add600, ffff888028ade018)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28ad8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88805a2bda81
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a44bb40 dead000000000100 dead000000000122
raw: 0000000000000000 00000000800b000b 00000000f5000000 ffff88805a2bda81
head: 00fff00000000040 ffff88801a44bb40 dead000000000100 dead000000000122
head: 0000000000000000 00000000800b000b 00000000f5000000 ffff88805a2bda81
head: 00fff00000000003 ffffea0000a2b601 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5500, tgid 5500 (dhcpcd), ts 59890243991, free_ts 59230696404
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1848
prep_new_page mm/page_alloc.c:1856 [inline]
get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
alloc_slab_page mm/slub.c:2487 [inline]
allocate_slab+0x8a/0x370 mm/slub.c:2655
new_slab mm/slub.c:2709 [inline]
___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
__slab_alloc mm/slub.c:3981 [inline]
__slab_alloc_node mm/slub.c:4056 [inline]
slab_alloc_node mm/slub.c:4217 [inline]
kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236
dup_mm kernel/fork.c:1466 [inline]
copy_mm+0xdb/0x4b0 kernel/fork.c:1528
copy_process+0x1706/0x3c00 kernel/fork.c:2168
kernel_clone+0x21e/0x870 kernel/fork.c:2598
__do_sys_clone kernel/fork.c:2741 [inline]
__se_sys_clone kernel/fork.c:2725 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5500 tgid 5500 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1392 [inline]
__free_frozen_pages+0xb80/0xd80 mm/page_alloc.c:2892
discard_slab mm/slub.c:2753 [inline]
__put_partials+0x156/0x1a0 mm/slub.c:3218
put_cpu_partial+0x17c/0x250 mm/slub.c:3293
__slab_free+0x2d5/0x3c0 mm/slub.c:4550
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281
__alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
alloc_skb include/linux/skbuff.h:1336 [inline]
alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6665
sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2974
unix_dgram_sendmsg+0x4f6/0x1870 net/unix/af_unix.c:2078
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x219/0x270 net/socket.c:729
sock_write_iter+0x258/0x330 net/socket.c:1179
do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1
vfs_writev+0x31a/0x960 fs/read_write.c:1057
Memory state around the buggy address:
ffff888028addf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888028addf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888028ade000: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff888028ade080: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
ffff888028ade100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
0: 48 21 c3 and %rax,%rbx
3: 0f 85 e9 01 00 00 jne 0x1f2
9: e8 b5 36 1f 00 call 0x1f36c3
e: 48 8b 5c 24 20 mov 0x20(%rsp),%rbx
13: 4d 85 f6 test %r14,%r14
16: 75 07 jne 0x1f
18: e8 a6 36 1f 00 call 0x1f36c3
1d: eb 06 jmp 0x25
1f: e8 9f 36 1f 00 call 0x1f36c3
24: fb sti
25: 48 8b 44 24 28 mov 0x28(%rsp),%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 df mov %rbx,%rdi
34: e8 0a 4a 83 00 call 0x834a43
39: 48 8b 1b mov (%rbx),%rbx
3c: 48 rex.W
3d: 8b .byte 0x8b
3e: 44 rex.R
3f: 24 .byte 0x24