[PATCH] KASAN: use-after-free Read in compute_effective_progs

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Tadeusz Struk

unread,
Apr 4, 2022, 1:37:25 PM4/4/22
to syzbot+f264bf...@syzkaller.appspotmail.com, syzkaller-a...@googlegroups.com, tadeus...@linaro.org
#syz test: https://android.googlesource.com/kernel/common android12-5.10

=======================================
index 6aa9e10c6335..0ad24a26f037 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -830,8 +830,7 @@ static void bpf_cgroup_link_release(struct bpf_link *link)
return;
}

- WARN_ON(__cgroup_bpf_detach(cg_link->cgroup, NULL, cg_link,
- cg_link->type));
+ __cgroup_bpf_detach(cg_link->cgroup, NULL, cg_link, cg_link->type);

cg = cg_link->cgroup;
cg_link->cgroup = NULL;
--
2.35.1

syzbot

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Apr 4, 2022, 1:47:22 PM4/4/22
to syzkaller-a...@googlegroups.com, tadeus...@linaro.org
Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: use-after-free Read in compute_effective_progs

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffeb201c0e0 R14: 00007ffeb201c120 R15: 0000000000000000
==================================================================
BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline]
BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline]
BUG: KASAN: use-after-free in compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
Read of size 8 at addr ffff88810afdc898 by task syz-executor148/407

CPU: 1 PID: 407 Comm: syz-executor148 Not tainted 5.10.101-syzkaller-00148-gceb6918d1d4a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
print_address_description+0x8d/0x3d0 mm/kasan/report.c:233
__kasan_report+0x142/0x220 mm/kasan/report.c:419
kasan_report+0x51/0x70 mm/kasan/report.c:436
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309
prog_list_prog kernel/bpf/cgroup.c:174 [inline]
prog_list_length kernel/bpf/cgroup.c:187 [inline]
compute_effective_progs+0x1d3/0x6e0 kernel/bpf/cgroup.c:240
update_effective_progs+0x79/0x310 kernel/bpf/cgroup.c:343
__cgroup_bpf_detach+0x312/0x570 kernel/bpf/cgroup.c:689
bpf_cgroup_link_release+0x94/0x230 kernel/bpf/cgroup.c:833
bpf_link_free kernel/bpf/syscall.c:2347 [inline]
bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2373
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2381
__fput+0x348/0x7d0 fs/file_table.c:281
____fput+0x15/0x20 fs/file_table.c:314
task_work_run+0x147/0x1b0 kernel/task_work.c:154
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
exit_to_user_mode_prepare+0xc3/0xe0 kernel/entry/common.c:191
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:266
do_syscall_64+0x3d/0x70 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fc740faf243
Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8
RSP: 002b:00007ffeb201c098 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 00007fc740faf243
RDX: 00000000000000c0 RSI: 0000000000000005 RDI: 0000000000000008
RBP: 00007ffeb201c0c0 R08: 0000000000000001 R09: 00007ffeb201c0d0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffeb201c0e0 R14: 00007ffeb201c120 R15: 0000000000000000

Allocated by task 407:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:428 [inline]
____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:507
__kasan_kmalloc+0x9/0x10 mm/kasan/common.c:516
kasan_kmalloc include/linux/kasan.h:269 [inline]
kmem_cache_alloc_trace+0x210/0x3a0 mm/slub.c:2983
kmalloc include/linux/slab.h:552 [inline]
kzalloc include/linux/slab.h:664 [inline]
cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:917
link_create kernel/bpf/syscall.c:4089 [inline]
__do_sys_bpf+0xab8e/0x116b0 kernel/bpf/syscall.c:4494
__se_sys_bpf kernel/bpf/syscall.c:4380 [inline]
__x64_sys_bpf+0x7a/0x90 kernel/bpf/syscall.c:4380
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 407:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:46
kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:357
____kasan_slab_free+0x133/0x170 mm/kasan/common.c:360
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:368
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:1604 [inline]
slab_free_freelist_hook+0xcc/0x1a0 mm/slub.c:1630
slab_free mm/slub.c:3212 [inline]
kfree+0xd5/0x320 mm/slub.c:4200
bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:848
bpf_link_free kernel/bpf/syscall.c:2351 [inline]
bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2373
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2381
__fput+0x348/0x7d0 fs/file_table.c:281
____fput+0x15/0x20 fs/file_table.c:314
task_work_run+0x147/0x1b0 kernel/task_work.c:154
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
exit_to_user_mode_prepare+0xc3/0xe0 kernel/entry/common.c:191
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:266
do_syscall_64+0x3d/0x70 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88810afdc880
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
96-byte region [ffff88810afdc880, ffff88810afdc8e0)
The buggy address belongs to the page:
page:ffffea00042bf700 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10afdc
flags: 0x8000000000000200(slab)
raw: 8000000000000200 ffffea00042beac0 0000001300000013 ffff888100043680
raw: 0000000000000000 0000000080200020 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 2335416101, free_ts 0
set_page_owner include/linux/page_owner.h:35 [inline]
post_alloc_hook mm/page_alloc.c:2385 [inline]
prep_new_page mm/page_alloc.c:2391 [inline]
get_page_from_freelist+0xa74/0xa90 mm/page_alloc.c:4067
__alloc_pages_nodemask+0x3c8/0x820 mm/page_alloc.c:5117
alloc_slab_page mm/slub.c:1815 [inline]
allocate_slab+0x6b/0x350 mm/slub.c:1817
new_slab mm/slub.c:1878 [inline]
new_slab_objects mm/slub.c:2637 [inline]
___slab_alloc+0x143/0x2f0 mm/slub.c:2800
__slab_alloc mm/slub.c:2840 [inline]
slab_alloc_node mm/slub.c:2922 [inline]
slab_alloc mm/slub.c:2964 [inline]
__kmalloc+0x2af/0x3d0 mm/slub.c:4038
kmalloc_array include/linux/slab.h:592 [inline]
kcalloc include/linux/slab.h:603 [inline]
cache_random_seq_create+0x81/0x1f0 mm/slab_common.c:909
init_cache_random_seq mm/slub.c:1695 [inline]
kmem_cache_open+0x44a/0x590 mm/slub.c:3898
__kmem_cache_create+0xf/0xd0 mm/slub.c:4512
create_cache mm/slab_common.c:258 [inline]
kmem_cache_create_usercopy+0x174/0x2a0 mm/slab_common.c:363
proto_register+0xed/0x880 net/core/sock.c:3485
inet6_init+0xc7/0x61c net/ipv6/af_inet6.c:1060
do_one_initcall+0x1d3/0x5f0 init/main.c:1209
do_initcall_level+0x182/0x2dd init/main.c:1282
do_initcalls+0x50/0x94 init/main.c:1298
do_basic_setup+0x7a/0x81 init/main.c:1318
kernel_init_freeable+0x2ba/0x3f4 init/main.c:1520
page_owner free stack trace missing

Memory state around the buggy address:
ffff88810afdc780: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
ffff88810afdc800: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88810afdc880: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff88810afdc900: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff88810afdc980: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
==================================================================


Tested on:

commit: ceb6918d ANDROID: vendor_hooks: Reduce pointless modve..
git tree: https://android.googlesource.com/kernel/common android12-5.10
console output: https://syzkaller.appspot.com/x/log.txt?x=167e6c85700000
kernel config: https://syzkaller.appspot.com/x/.config?x=1ff3b8aff389a956
dashboard link: https://syzkaller.appspot.com/bug?extid=f264bffdfbd5614f3bb2
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=137ce16f700000

Tadeusz Struk

unread,
Apr 4, 2022, 1:55:11 PM4/4/22
to syzbot, syzkaller-a...@googlegroups.com
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

syzbot

unread,
Apr 4, 2022, 2:04:20 PM4/4/22
to syzkaller-a...@googlegroups.com, tadeus...@linaro.org
Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: use-after-free Read in compute_effective_progs

R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffed93c1140 R14: 00007ffed93c1180 R15: 0000000000000000
</TASK>
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline]
BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline]
BUG: KASAN: use-after-free in compute_effective_progs+0x1a1/0x620 kernel/bpf/cgroup.c:240
Read of size 8 at addr ffff8881089f8c98 by task syz-executor165/411

CPU: 1 PID: 411 Comm: syz-executor165 Tainted: G W 5.18.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:313 [inline]
print_report+0x166/0x620 mm/kasan/report.c:429
kasan_report+0xee/0x120 mm/kasan/report.c:491
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:307
prog_list_prog kernel/bpf/cgroup.c:174 [inline]
prog_list_length kernel/bpf/cgroup.c:187 [inline]
compute_effective_progs+0x1a1/0x620 kernel/bpf/cgroup.c:240
update_effective_progs+0x79/0x320 kernel/bpf/cgroup.c:343
__cgroup_bpf_detach+0x2fa/0x550 kernel/bpf/cgroup.c:725
bpf_cgroup_link_release+0x94/0x260 kernel/bpf/cgroup.c:899
bpf_link_free kernel/bpf/syscall.c:2469 [inline]
bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2495
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2504
__fput+0x3ee/0x890 fs/file_table.c:317
____fput+0x15/0x20 fs/file_table.c:350
task_work_run+0x147/0x1b0 kernel/task_work.c:164
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop kernel/entry/common.c:169 [inline]
exit_to_user_mode_prepare+0xe0/0xf0 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:294
do_syscall_64+0x3e/0x50 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f7c30942243
Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8
RSP: 002b:00007ffed93c10f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 00007f7c30942243
RDX: 0000000000000120 RSI: 0000000000000005 RDI: 0000000000000008
RBP: 00007ffed93c1120 R08: 0000000000000001 R09: 00007ffed93c1130
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffed93c1140 R14: 00007ffed93c1180 R15: 0000000000000000
</TASK>

Allocated by task 411:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:436 [inline]
____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:515
__kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524
kasan_kmalloc include/linux/kasan.h:234 [inline]
kmem_cache_alloc_trace+0x22e/0x3a0 mm/slub.c:3258
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:984
link_create kernel/bpf/syscall.c:4320 [inline]
__sys_bpf+0x996e/0x123e0 kernel/bpf/syscall.c:4733
__do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:4765
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 411:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4c/0x70 mm/kasan/common.c:45
kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
____kasan_slab_free+0x140/0x180 mm/kasan/common.c:366
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:374
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1728 [inline]
slab_free_freelist_hook+0xc9/0x1a0 mm/slub.c:1754
slab_free mm/slub.c:3510 [inline]
kfree+0xc0/0x2a0 mm/slub.c:4552
bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:915
bpf_link_free kernel/bpf/syscall.c:2473 [inline]
bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2495
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2504
__fput+0x3ee/0x890 fs/file_table.c:317
____fput+0x15/0x20 fs/file_table.c:350
task_work_run+0x147/0x1b0 kernel/task_work.c:164
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop kernel/entry/common.c:169 [inline]
exit_to_user_mode_prepare+0xe0/0xf0 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:294
do_syscall_64+0x3e/0x50 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff8881089f8c80
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
96-byte region [ffff8881089f8c80, ffff8881089f8ce0)

The buggy address belongs to the physical page:
page:ffffea0004227e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1089f8
flags: 0x8000000000000200(slab|zone=2)
raw: 8000000000000200 ffffea0004223c80 dead000000000006 ffff888100041780
raw: 0000000000000000 0000000080200020 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 1149046317, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x161/0x170 mm/page_alloc.c:2434
prep_new_page mm/page_alloc.c:2441 [inline]
get_page_from_freelist+0x3a7/0xae0 mm/page_alloc.c:4182
__alloc_pages+0x3bd/0x830 mm/page_alloc.c:5408
allocate_slab+0x67/0x320 mm/slub.c:1944
new_slab mm/slub.c:2004 [inline]
___slab_alloc+0x1d2/0x4a0 mm/slub.c:3005
__slab_alloc mm/slub.c:3092 [inline]
slab_alloc_node mm/slub.c:3183 [inline]
slab_alloc mm/slub.c:3225 [inline]
kmem_cache_alloc_trace+0x289/0x3a0 mm/slub.c:3256
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
locate_module_kobject+0x74/0x168 kernel/params.c:771
version_sysfs_builtin+0x64/0xd0 kernel/params.c:874
param_sysfs_init+0x67/0x71 kernel/params.c:969
do_one_initcall+0x1c3/0x5d0 init/main.c:1298
do_initcall_level+0x182/0x2dd init/main.c:1371
do_initcalls+0x50/0x94 init/main.c:1387
do_basic_setup+0x73/0x7a init/main.c:1406
kernel_init_freeable+0x2bd/0x3f6 init/main.c:1613
kernel_init+0x1d/0x2b0 init/main.c:1502
ret_from_fork+0x1f/0x30
page_owner free stack trace missing

Memory state around the buggy address:
ffff8881089f8b80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
ffff8881089f8c00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff8881089f8c80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff8881089f8d00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff8881089f8d80: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
==================================================================


Tested on:

commit: 31231092 Linux 5.18-rc1
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=143e6a0d700000
kernel config: https://syzkaller.appspot.com/x/.config?x=43e74a6abb9c3fce
dashboard link: https://syzkaller.appspot.com/bug?extid=f264bffdfbd5614f3bb2
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.

Tadeusz Struk

unread,
Apr 4, 2022, 2:07:17 PM4/4/22
to syzbot+f264bf...@syzkaller.appspotmail.com, syzkaller-a...@googlegroups.com, tadeus...@linaro.org
#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

syzbot

unread,
Apr 4, 2022, 2:16:08 PM4/4/22
to syzkaller-a...@googlegroups.com, tadeus...@linaro.org
Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: use-after-free Read in compute_effective_progs

RDX: 0000000000000460 RSI: 0000000000000005 RDI: 0000000000000003
RBP: 00007ffd0c5c2460 R08: 0000000000000001 R09: 00007ffd0c5c2470
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffd0c5c2480 R14: 00007ffd0c5c24c0 R15: 0000000000000000
</TASK>
==================================================================
BUG: KASAN: use-after-free in prog_list_prog kernel/bpf/cgroup.c:174 [inline]
BUG: KASAN: use-after-free in prog_list_length kernel/bpf/cgroup.c:187 [inline]
BUG: KASAN: use-after-free in compute_effective_progs+0x1a1/0x620 kernel/bpf/cgroup.c:240
Read of size 8 at addr ffff88810922f018 by task syz-executor293/423

CPU: 0 PID: 423 Comm: syz-executor293 Not tainted 5.18.0-rc1-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:313 [inline]
print_report+0x166/0x620 mm/kasan/report.c:429
kasan_report+0xee/0x120 mm/kasan/report.c:491
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:307
prog_list_prog kernel/bpf/cgroup.c:174 [inline]
prog_list_length kernel/bpf/cgroup.c:187 [inline]
compute_effective_progs+0x1a1/0x620 kernel/bpf/cgroup.c:240
update_effective_progs+0x79/0x320 kernel/bpf/cgroup.c:343
__cgroup_bpf_detach+0x2fa/0x550 kernel/bpf/cgroup.c:725
bpf_cgroup_link_release+0x94/0x230 kernel/bpf/cgroup.c:899
bpf_link_free kernel/bpf/syscall.c:2469 [inline]
bpf_link_put+0x1e9/0x270 kernel/bpf/syscall.c:2495
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2504
__fput+0x3ee/0x890 fs/file_table.c:317
____fput+0x15/0x20 fs/file_table.c:350
task_work_run+0x147/0x1b0 kernel/task_work.c:164
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop kernel/entry/common.c:169 [inline]
exit_to_user_mode_prepare+0xe0/0xf0 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:294
do_syscall_64+0x3e/0x50 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f39d9de4243
Code: c7 c2 c0 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb ba 0f 1f 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8
RSP: 002b:00007ffd0c5c2438 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000009 RCX: 00007f39d9de4243
RDX: 0000000000000460 RSI: 0000000000000005 RDI: 0000000000000008
RBP: 00007ffd0c5c2460 R08: 0000000000000001 R09: 00007ffd0c5c2470
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffd0c5c2480 R14: 00007ffd0c5c24c0 R15: 0000000000000000
</TASK>

Allocated by task 423:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:436 [inline]
____kasan_kmalloc+0xdc/0x110 mm/kasan/common.c:515
__kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524
kasan_kmalloc include/linux/kasan.h:234 [inline]
kmem_cache_alloc_trace+0x22e/0x3a0 mm/slub.c:3258
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
cgroup_bpf_link_attach+0x12e/0x4a0 kernel/bpf/cgroup.c:983
link_create kernel/bpf/syscall.c:4320 [inline]
__sys_bpf+0x996e/0x123e0 kernel/bpf/syscall.c:4733
__do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:4765
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 423:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track+0x4c/0x70 mm/kasan/common.c:45
kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
____kasan_slab_free+0x140/0x180 mm/kasan/common.c:366
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:374
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1728 [inline]
slab_free_freelist_hook+0xc9/0x1a0 mm/slub.c:1754
slab_free mm/slub.c:3510 [inline]
kfree+0xc0/0x2a0 mm/slub.c:4552
bpf_cgroup_link_dealloc+0x15/0x20 kernel/bpf/cgroup.c:914
bpf_link_free kernel/bpf/syscall.c:2473 [inline]
bpf_link_put+0x243/0x270 kernel/bpf/syscall.c:2495
bpf_link_release+0x3b/0x40 kernel/bpf/syscall.c:2504
__fput+0x3ee/0x890 fs/file_table.c:317
____fput+0x15/0x20 fs/file_table.c:350
task_work_run+0x147/0x1b0 kernel/task_work.c:164
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop kernel/entry/common.c:169 [inline]
exit_to_user_mode_prepare+0xe0/0xf0 kernel/entry/common.c:201
__syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
syscall_exit_to_user_mode+0x24/0x40 kernel/entry/common.c:294
do_syscall_64+0x3e/0x50 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88810922f000
which belongs to the cache kmalloc-96 of size 96
The buggy address is located 24 bytes inside of
96-byte region [ffff88810922f000, ffff88810922f060)

The buggy address belongs to the physical page:
page:ffffea0004248bc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10922f
flags: 0x8000000000000200(slab|zone=2)
raw: 8000000000000200 ffffea0004248940 dead000000000005 ffff888100041780
raw: 0000000000000000 0000000080200020 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, tgid 1 (swapper/0), ts 1364686773, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x161/0x170 mm/page_alloc.c:2434
prep_new_page mm/page_alloc.c:2441 [inline]
get_page_from_freelist+0x3a7/0xae0 mm/page_alloc.c:4182
__alloc_pages+0x3bd/0x830 mm/page_alloc.c:5408
allocate_slab+0x67/0x320 mm/slub.c:1944
new_slab mm/slub.c:2004 [inline]
___slab_alloc+0x1d2/0x4a0 mm/slub.c:3005
__slab_alloc mm/slub.c:3092 [inline]
slab_alloc_node mm/slub.c:3183 [inline]
slab_alloc mm/slub.c:3225 [inline]
kmem_cache_alloc_trace+0x289/0x3a0 mm/slub.c:3256
kmalloc include/linux/slab.h:581 [inline]
kzalloc include/linux/slab.h:714 [inline]
acpi_os_allocate_zeroed include/acpi/platform/aclinuxex.h:57 [inline]
acpi_evaluate_object+0x155/0xac9 drivers/acpi/acpica/nsxfeval.c:177
acpi_evaluate_integer+0x124/0x240 drivers/acpi/utils.c:260
acpi_bus_get_status_handle drivers/acpi/bus.c:84 [inline]
acpi_bus_get_status+0x14e/0x250 drivers/acpi/bus.c:113
acpi_bus_attach+0x294/0xdc0 drivers/acpi/scan.c:2216
acpi_bus_attach+0x3bc/0xdc0 drivers/acpi/scan.c:2259
acpi_bus_attach+0x3bc/0xdc0 drivers/acpi/scan.c:2259
acpi_bus_scan+0x10a/0x200 drivers/acpi/scan.c:2448
acpi_scan_init+0x276/0x75b drivers/acpi/scan.c:2613
acpi_init+0x148/0x1fb drivers/acpi/bus.c:1361
do_one_initcall+0x1c3/0x5d0 init/main.c:1298
page_owner free stack trace missing

Memory state around the buggy address:
ffff88810922ef00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88810922ef80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88810922f000: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
^
ffff88810922f080: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff88810922f100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================


Tested on:

commit: 31231092 Linux 5.18-rc1
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=12710b87700000
kernel config: https://syzkaller.appspot.com/x/.config?x=43e74a6abb9c3fce
dashboard link: https://syzkaller.appspot.com/bug?extid=f264bffdfbd5614f3bb2
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=16ebe44b700000

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