==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:980 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:560 [inline]
BUG: KASAN: slab-use-after-free in __ep_remove+0x8de/0xa70 fs/eventpoll.c:864
Write of size 8 at addr ffff88804a6a29b8 by task syz.5.2119/12881
CPU: 1 UID: 0 PID: 12881 Comm: syz.5.2119 Not tainted 6.15.0-syzkaller-10769-g7d4e49a77d99 #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xcd/0x680 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
__hlist_del include/linux/list.h:980 [inline]
hlist_del_rcu include/linux/rculist.h:560 [inline]
__ep_remove+0x8de/0xa70 fs/eventpoll.c:864
ep_remove_safe fs/eventpoll.c:894 [inline]
ep_clear_and_put+0x226/0x440 fs/eventpoll.c:930
ep_eventpoll_release+0x3e/0x60 fs/eventpoll.c:967
__fput+0x3ff/0xb70 fs/file_table.c:465
task_work_run+0x150/0x240 kernel/task_work.c:227
get_signal+0x1d1/0x26d0 kernel/signal.c:2807
arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
__do_fast_syscall_32+0x2ac/0x3a0 arch/x86/entry/syscall_32.c:309
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f56579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f505555c EFLAGS: 00000296 ORIG_RAX: 000000000000013f
RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 0000000080000080
RDX: 0000000000000001 RSI: 0000000080000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Allocated by task 12880:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
ep_alloc fs/eventpoll.c:1151 [inline]
do_epoll_create+0x62/0x470 fs/eventpoll.c:2239
__do_sys_epoll_create1 fs/eventpoll.c:2270 [inline]
__se_sys_epoll_create1 fs/eventpoll.c:2268 [inline]
__ia32_sys_epoll_create1+0x30/0x40 fs/eventpoll.c:2268
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x7c/0x3a0 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
Freed by task 12880:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4841
ep_free fs/eventpoll.c:821 [inline]
ep_clear_and_put+0x3a6/0x440 fs/eventpoll.c:938
ep_eventpoll_release+0x3e/0x60 fs/eventpoll.c:967
__fput+0x3ff/0xb70 fs/file_table.c:465
task_work_run+0x150/0x240 kernel/task_work.c:227
get_signal+0x1d1/0x26d0 kernel/signal.c:2807
arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
__do_fast_syscall_32+0x2ac/0x3a0 arch/x86/entry/syscall_32.c:309
do_fast_syscall_32+0x32/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
The buggy address belongs to the object at ffff88804a6a2800
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 440 bytes inside of
freed 512-byte region [ffff88804a6a2800, ffff88804a6a2a00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4a6a0
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000040 ffff88801b442c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 04fff00000000040 ffff88801b442c80 0000000000000000 dead000000000001
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 04fff00000000002 ffffea000129a801 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 18914196947, free_ts 0
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
prep_new_page mm/page_alloc.c:1712 [inline]
get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
__alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
alloc_slab_page mm/slub.c:2450 [inline]
allocate_slab mm/slub.c:2618 [inline]
new_slab+0x23b/0x330 mm/slub.c:2672
___slab_alloc+0xd9c/0x1940 mm/slub.c:3858
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948
__slab_alloc_node mm/slub.c:4023 [inline]
slab_alloc_node mm/slub.c:4184 [inline]
__do_kmalloc_node mm/slub.c:4326 [inline]
__kmalloc_node_track_caller_noprof+0x2ee/0x510 mm/slub.c:4346
__do_krealloc mm/slub.c:4904 [inline]
krealloc_noprof+0x156/0x370 mm/slub.c:4957
add_sysfs_param+0xd3/0xa00 kernel/params.c:654
kernel_add_sysfs_param kernel/params.c:811 [inline]
param_sysfs_builtin kernel/params.c:850 [inline]
param_sysfs_builtin_init+0x307/0x4c0 kernel/params.c:986
do_one_initcall+0x120/0x6e0 init/main.c:1273
do_initcall_level init/main.c:1335 [inline]
do_initcalls init/main.c:1351 [inline]
do_basic_setup init/main.c:1370 [inline]
kernel_init_freeable+0x5c2/0x900 init/main.c:1583
kernel_init+0x1c/0x2b0 init/main.c:1473
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing
Memory state around the buggy address:
ffff88804a6a2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88804a6a2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88804a6a2980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88804a6a2a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88804a6a2a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 10 06 adc %al,(%rsi)
2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi
6: 10 07 adc %al,(%rdi)
8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi
c: 10 08 adc %cl,(%rax)
e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi
1e: 00 51 52 add %dl,0x52(%rcx)
21: 55 push %rbp
22: 89 e5 mov %esp,%ebp
24: 0f 34 sysenter
26: cd 80 int $0x80
* 28: 5d pop %rbp <-- trapping instruction
29: 5a pop %rdx
2a: 59 pop %rcx
2b: c3 ret
2c: 90 nop
2d: 90 nop
2e: 90 nop
2f: 90 nop
30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi