[Android 5.4] KASAN: use-after-free Write in enqueue_timer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6a5ec6cea0cd UPSTREAM: 9p/fd: fix issue of list_del corrup..
git tree: android12-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=12c4a800c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=e270749e5a0ba365
dashboard link: https://syzkaller.appspot.com/bug?extid=2c452f99424f8e4e79a8
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/68d94ce466da/disk-6a5ec6ce.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/edf99d431199/vmlinux-6a5ec6ce.xz
kernel image: https://storage.googleapis.com/syzbot-assets/685ae70c99ed/bzImage-6a5ec6ce.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2c452f...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:796 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0x99/0x2d0 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e0cbf1c8 by task syz-executor.4/6153

CPU: 0 PID: 6153 Comm: syz-executor.4 Not tainted 5.4.225-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d8/0x241 lib/dump_stack.c:118
print_address_description+0x8c/0x600 mm/kasan/report.c:384
__kasan_report+0xf3/0x120 mm/kasan/report.c:516
kasan_report+0x30/0x60 mm/kasan/common.c:653
hlist_add_head include/linux/list.h:796 [inline]
enqueue_timer+0x99/0x2d0 kernel/time/timer.c:541
__internal_add_timer kernel/time/timer.c:554 [inline]
internal_add_timer+0x240/0x430 kernel/time/timer.c:604
__mod_timer+0x8a0/0x1480 kernel/time/timer.c:1065
tun_set_iff+0x8ed/0x10c0 drivers/net/tun.c:2874
__tun_chr_ioctl+0x806/0x1ed0 drivers/net/tun.c:3169
do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
ksys_ioctl fs/ioctl.c:742 [inline]
__do_sys_ioctl fs/ioctl.c:749 [inline]
__se_sys_ioctl fs/ioctl.c:747 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1

The buggy address belongs to the page:
page:ffffea0007832fc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffffff06c10101 0000000000000000
raw: 0000000000000000 00000000000c0000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x146dc0(GFP_USER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP|__GFP_ZERO)
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook mm/page_alloc.c:2165 [inline]
prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
get_page_from_freelist+0x2ce8/0x2d70 mm/page_alloc.c:3794
__alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891
__alloc_pages include/linux/gfp.h:503 [inline]
__alloc_pages_node include/linux/gfp.h:516 [inline]
alloc_pages_node include/linux/gfp.h:530 [inline]
kmalloc_order mm/slab_common.c:1342 [inline]
kmalloc_order_trace+0x2a/0x100 mm/slab_common.c:1358
__kmalloc_node include/linux/slab.h:422 [inline]
kmalloc_node include/linux/slab.h:599 [inline]
kvmalloc_node+0x7e/0xf0 mm/util.c:596
kvmalloc include/linux/mm.h:759 [inline]
kvzalloc include/linux/mm.h:767 [inline]
alloc_netdev_mqs+0x85/0xc70 net/core/dev.c:9598
tun_set_iff+0x516/0x10c0 drivers/net/tun.c:2834
__tun_chr_ioctl+0x806/0x1ed0 drivers/net/tun.c:3169
do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
ksys_ioctl fs/ioctl.c:742 [inline]
__do_sys_ioctl fs/ioctl.c:749 [inline]
__se_sys_ioctl fs/ioctl.c:747 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1176 [inline]
__free_pages_ok+0x83d/0x940 mm/page_alloc.c:1438
free_the_page mm/page_alloc.c:4953 [inline]
__free_pages+0x91/0x140 mm/page_alloc.c:4959
device_release+0x6b/0x190 drivers/base/core.c:1776
kobject_cleanup lib/kobject.c:708 [inline]
kobject_release lib/kobject.c:739 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1e6/0x2f0 lib/kobject.c:756
tun_set_iff+0xc48/0x10c0 drivers/net/tun.c:2926
__tun_chr_ioctl+0x806/0x1ed0 drivers/net/tun.c:3169
do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
ksys_ioctl fs/ioctl.c:742 [inline]
__do_sys_ioctl fs/ioctl.c:749 [inline]
__se_sys_ioctl fs/ioctl.c:747 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
ffff8881e0cbf080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e0cbf100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e0cbf180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881e0cbf200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881e0cbf280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: a9527bd839f6 UPSTREAM: net/sched: cls_u32: Fix reference c..
git tree: android12-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=16ded7b0a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=98c345379e95bc57

dashboard link: https://syzkaller.appspot.com/bug?extid=2c452f99424f8e4e79a8
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16560893280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1619f33f280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/712460ab3b5c/disk-a9527bd8.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9d6e67c60aed/vmlinux-a9527bd8.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c6d2f7132e1f/bzImage-a9527bd8.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2c452f...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:796 [inline]

BUG: KASAN: use-after-free in enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
Write of size 8 at addr ffff8881ec4431c8 by task syz-executor266/1994

CPU: 0 PID: 1994 Comm: syz-executor266 Not tainted 5.4.242-syzkaller-00016-ga9527bd839f6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
<IRQ>

__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d8/0x241 lib/dump_stack.c:118
print_address_description+0x8c/0x600 mm/kasan/report.c:384
__kasan_report+0xf3/0x120 mm/kasan/report.c:516
kasan_report+0x30/0x60 mm/kasan/common.c:653
hlist_add_head include/linux/list.h:796 [inline]

enqueue_timer+0xb7/0x300 kernel/time/timer.c:541

__internal_add_timer kernel/time/timer.c:554 [inline]
internal_add_timer+0x240/0x430 kernel/time/timer.c:604

__mod_timer+0x6f1/0x13e0 kernel/time/timer.c:1065
call_timer_fn+0x36/0x390 kernel/time/timer.c:1418
expire_timers kernel/time/timer.c:1463 [inline]
__run_timers+0x879/0xbe0 kernel/time/timer.c:1787
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1800
__do_softirq+0x23b/0x6b7 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x195/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:538 [inline]
smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1150
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
</IRQ>

The buggy address belongs to the page:

page:ffffea0007b110c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000

page dumped because: kasan: bad access detected
page_owner tracks the page as freed

page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140dc0(GFP_USER|__GFP_COMP|__GFP_ZERO)

set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook mm/page_alloc.c:2165 [inline]
prep_new_page+0x18f/0x370 mm/page_alloc.c:2171

get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794

__alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4891
__alloc_pages include/linux/gfp.h:503 [inline]
__alloc_pages_node include/linux/gfp.h:516 [inline]
alloc_pages_node include/linux/gfp.h:530 [inline]
kmalloc_order mm/slab_common.c:1342 [inline]
kmalloc_order_trace+0x2a/0x100 mm/slab_common.c:1358

kmalloc_large include/linux/slab.h:485 [inline]
kmalloc include/linux/slab.h:549 [inline]
kzalloc include/linux/slab.h:690 [inline]
bpf_check+0xf6/0xb340 kernel/bpf/verifier.c:9556
bpf_prog_load kernel/bpf/syscall.c:1724 [inline]
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x8139/0xbcb0 kernel/bpf/syscall.c:2849

do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1176 [inline]

__free_pages_ok+0x847/0x950 mm/page_alloc.c:1438

free_the_page mm/page_alloc.c:4953 [inline]
__free_pages+0x91/0x140 mm/page_alloc.c:4959

bpf_check+0x8aaa/0xb340 kernel/bpf/verifier.c:9726
bpf_prog_load kernel/bpf/syscall.c:1724 [inline]
__do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
__se_sys_bpf+0x8139/0xbcb0 kernel/bpf/syscall.c:2849

do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:

ffff8881ec443080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881ec443100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881ec443180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881ec443200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881ec443280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 0 P4D 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 630 Comm: syz-executor266 Tainted: G B 5.4.242-syzkaller-00016-ga9527bd839f6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202
RAX: ffffffff8154cc2a RBX: 0000000000000101 RCX: ffff8881dc431f80
RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881ec4431c0
RBP: ffff8881f6e09ec8 R08: ffffffff8154c86e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000100000c88
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ec4431c0
FS: 00005555556da400(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dc79d000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
call_timer_fn+0x36/0x390 kernel/time/timer.c:1418
expire_timers kernel/time/timer.c:1463 [inline]
__run_timers+0x879/0xbe0 kernel/time/timer.c:1787
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1800
__do_softirq+0x23b/0x6b7 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x195/0x1c0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:538 [inline]
smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1150
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834
</IRQ>
Modules linked in:
CR2: 0000000000000000
---[ end trace 3a0f80b832eec789 ]---
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0018:ffff8881f6e09d18 EFLAGS: 00010202
RAX: ffffffff8154cc2a RBX: 0000000000000101 RCX: ffff8881dc431f80
RDX: 0000000000000101 RSI: 0000000000000000 RDI: ffff8881ec4431c0
RBP: ffff8881f6e09ec8 R08: ffffffff8154c86e R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000100000c88
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881ec4431c0
FS: 00005555556da400(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001dc79d000 CR4: 00000000003406b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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