Re: KASAN: invalid-access Write in enqueue_timer
On Tue, Feb 16, 2021 at 7:15 PM Dmitry Vyukov wrote:
> > On Tue, Feb 16, 2021 at 06:50:20PM +0100, Jason A. Donenfeld wrote:
> > > On Tue, Feb 16, 2021 at 6:46 PM Jason A. Donenfeld
> > > wrote:
> > > > On Tue, Feb 16, 2021 at 6:28 PM Catalin Marinas
> > > > wrote:
> > > > > > hlist_add_head include/linux/list.h:883 [inline]
> > > > > > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
> > > > > > mod_timer+0x14/0x20 kernel/time/timer.c:1106
> > > > > > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
> > > > > > wg_timers_any_authenticated_packet_traversal+0x68/0x90
> > > > > > drivers/net/wireguard/timers.c:215
> > > >
> > > > The line of hlist_add_head that it's hitting is:
> > > >
> > > > static inline void hlist_add_head(struct hlist_node *n, struct
> > > > hlist_head *h)
> > > > {
> > > >struct hlist_node *first = h->first;
> > > >WRITE_ONCE(n->next, first);
> > > >if (first)
> > > >
> > > > So that means it's the dereferencing of h that's a problem. That comes
> > > > from:
> > > >
> > > > static void enqueue_timer(struct timer_base *base, struct timer_list
> > > > *timer,
> > > > unsigned int idx, unsigned long bucket_expiry)
> > > > {
> > > >
> > > >hlist_add_head(>entry, base->vectors + idx);
> > > >
> > > > That means it concerns base->vectors + idx, not the timer_list object
> > > > that wireguard manages. That's confusing. Could that imply that the
> > > > bug is in freeing a previous timer without removing it from the timer
> > > > lists, so that it winds up being in base->vectors?
> >
> > Good point, it's indeed likely that the timer list is messed up already,
> > just an unlucky encounter in the wireguard code.
> >
> > > Digging around on syzkaller, it looks like there's a similar bug on
> > > jbd2, concerning iptunnels's allocation:
> > >
> > > https://syzkaller.appspot.com/text?tag=CrashReport=13afb19cd0
> > [...]
> > > It might not actually be a wireguard bug?
> >
> > I wonder whether syzbot reported similar issues with
> > CONFIG_KASAN_SW_TAGS. It shouldn't be that different from the HW_TAGS
> > but at least we can rule out qemu bugs with the MTE emulation.
>
> +Eric
I've seen some similar reports on other syzkaller instances. They all
have similar alloc/free stacks, but different access stacks.
This does not seem to be wireguard nor arm/mte related. It seems that
something released the device prematurely, and then some innocent code
gets a use-after-free.
Re: KASAN: invalid-access Write in enqueue_timer
On Tue, Feb 16, 2021 at 7:01 PM Catalin Marinas wrote:
>
> On Tue, Feb 16, 2021 at 06:50:20PM +0100, Jason A. Donenfeld wrote:
> > On Tue, Feb 16, 2021 at 6:46 PM Jason A. Donenfeld wrote:
> > > On Tue, Feb 16, 2021 at 6:28 PM Catalin Marinas
> > > wrote:
> > > > > hlist_add_head include/linux/list.h:883 [inline]
> > > > > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
> > > > > mod_timer+0x14/0x20 kernel/time/timer.c:1106
> > > > > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
> > > > > wg_timers_any_authenticated_packet_traversal+0x68/0x90
> > > > > drivers/net/wireguard/timers.c:215
> > >
> > > The line of hlist_add_head that it's hitting is:
> > >
> > > static inline void hlist_add_head(struct hlist_node *n, struct hlist_head
> > > *h)
> > > {
> > >struct hlist_node *first = h->first;
> > >WRITE_ONCE(n->next, first);
> > >if (first)
> > >
> > > So that means it's the dereferencing of h that's a problem. That comes
> > > from:
> > >
> > > static void enqueue_timer(struct timer_base *base, struct timer_list
> > > *timer,
> > > unsigned int idx, unsigned long bucket_expiry)
> > > {
> > >
> > >hlist_add_head(>entry, base->vectors + idx);
> > >
> > > That means it concerns base->vectors + idx, not the timer_list object
> > > that wireguard manages. That's confusing. Could that imply that the
> > > bug is in freeing a previous timer without removing it from the timer
> > > lists, so that it winds up being in base->vectors?
>
> Good point, it's indeed likely that the timer list is messed up already,
> just an unlucky encounter in the wireguard code.
>
> > Digging around on syzkaller, it looks like there's a similar bug on
> > jbd2, concerning iptunnels's allocation:
> >
> > https://syzkaller.appspot.com/text?tag=CrashReport=13afb19cd0
> [...]
> > It might not actually be a wireguard bug?
>
> I wonder whether syzbot reported similar issues with
> CONFIG_KASAN_SW_TAGS. It shouldn't be that different from the HW_TAGS
> but at least we can rule out qemu bugs with the MTE emulation.
+Eric
Re: KASAN: invalid-access Write in enqueue_timer
On Tue, Feb 16, 2021 at 06:50:20PM +0100, Jason A. Donenfeld wrote:
> On Tue, Feb 16, 2021 at 6:46 PM Jason A. Donenfeld wrote:
> > On Tue, Feb 16, 2021 at 6:28 PM Catalin Marinas
> > wrote:
> > > > hlist_add_head include/linux/list.h:883 [inline]
> > > > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
> > > > mod_timer+0x14/0x20 kernel/time/timer.c:1106
> > > > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
> > > > wg_timers_any_authenticated_packet_traversal+0x68/0x90
> > > > drivers/net/wireguard/timers.c:215
> >
> > The line of hlist_add_head that it's hitting is:
> >
> > static inline void hlist_add_head(struct hlist_node *n, struct hlist_head
> > *h)
> > {
> >struct hlist_node *first = h->first;
> >WRITE_ONCE(n->next, first);
> >if (first)
> >
> > So that means it's the dereferencing of h that's a problem. That comes from:
> >
> > static void enqueue_timer(struct timer_base *base, struct timer_list *timer,
> > unsigned int idx, unsigned long bucket_expiry)
> > {
> >
> >hlist_add_head(>entry, base->vectors + idx);
> >
> > That means it concerns base->vectors + idx, not the timer_list object
> > that wireguard manages. That's confusing. Could that imply that the
> > bug is in freeing a previous timer without removing it from the timer
> > lists, so that it winds up being in base->vectors?
Good point, it's indeed likely that the timer list is messed up already,
just an unlucky encounter in the wireguard code.
> Digging around on syzkaller, it looks like there's a similar bug on
> jbd2, concerning iptunnels's allocation:
>
> https://syzkaller.appspot.com/text?tag=CrashReport=13afb19cd0
[...]
> It might not actually be a wireguard bug?
I wonder whether syzbot reported similar issues with
CONFIG_KASAN_SW_TAGS. It shouldn't be that different from the HW_TAGS
but at least we can rule out qemu bugs with the MTE emulation.
--
Catalin
Re: KASAN: invalid-access Write in enqueue_timer
On Tue, Feb 16, 2021 at 6:46 PM Jason A. Donenfeld wrote:
>
> Hi Catalin,
>
> On Tue, Feb 16, 2021 at 6:28 PM Catalin Marinas
> wrote:
> > Adding Jason and Ard. It may be a use-after-free in the wireguard
> > driver.
>
> Thanks for sending this my way. Note: to my knowledge, Ard doesn't
> work on wireguard.
>
> > > hlist_add_head include/linux/list.h:883 [inline]
> > > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
> > > mod_timer+0x14/0x20 kernel/time/timer.c:1106
> > > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
> > > wg_timers_any_authenticated_packet_traversal+0x68/0x90
> > > drivers/net/wireguard/timers.c:215
>
> The line of hlist_add_head that it's hitting is:
>
> static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
> {
>struct hlist_node *first = h->first;
>WRITE_ONCE(n->next, first);
>if (first)
>
> So that means it's the dereferencing of h that's a problem. That comes from:
>
> static void enqueue_timer(struct timer_base *base, struct timer_list *timer,
> unsigned int idx, unsigned long bucket_expiry)
> {
>
>hlist_add_head(>entry, base->vectors + idx);
>
> That means it concerns base->vectors + idx, not the timer_list object
> that wireguard manages. That's confusing. Could that imply that the
> bug is in freeing a previous timer without removing it from the timer
> lists, so that it winds up being in base->vectors?
>
> The allocation and deallocation backtrace is confusing
>
> > > alloc_netdev_mqs+0x5c/0x3bc net/core/dev.c:10546
> > > rtnl_create_link+0xc8/0x2b0 net/core/rtnetlink.c:3171
> > > __rtnl_newlink+0x5bc/0x800 net/core/rtnetlink.c:3433
>
> This suggests it's part of the `ip link add wg0 type wireguard` nelink
> call, during it's allocation of the netdevice's private area. For
> this, the wg_device struct is used. It has no timer_list structures in
> it!
>
> Similarly,
>
> > > netdev_freemem+0x18/0x2c net/core/dev.c:10500
> > > netdev_release+0x30/0x44 net/core/net-sysfs.c:1828
> > > device_release+0x34/0x90 drivers/base/core.c:1980
>
> That smells like `ip link del wg0 type wireguard`. But again,
> wg_device doesn't have any timer_lists in it.
>
> So what's happening here exactly? I'm not really sure yet...
>
> It'd be nice to have a reproducer.
>
>
> Jason
Digging around on syzkaller, it looks like there's a similar bug on
jbd2, concerning iptunnels's allocation:
https://syzkaller.appspot.com/text?tag=CrashReport=13afb19cd0
And one from ext4:
https://syzkaller.appspot.com/text?tag=CrashReport=17685330d0
And from from ext4 with fddup:
https://syzkaller.appspot.com/text?tag=CrashReport=17685330d0
https://syzkaller.appspot.com/text?tag=CrashReport=12d326e8d0
It might not actually be a wireguard bug?
Re: KASAN: invalid-access Write in enqueue_timer
Hi Catalin,
On Tue, Feb 16, 2021 at 6:28 PM Catalin Marinas wrote:
> Adding Jason and Ard. It may be a use-after-free in the wireguard
> driver.
Thanks for sending this my way. Note: to my knowledge, Ard doesn't
work on wireguard.
> > hlist_add_head include/linux/list.h:883 [inline]
> > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581
> > mod_timer+0x14/0x20 kernel/time/timer.c:1106
> > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
> > wg_timers_any_authenticated_packet_traversal+0x68/0x90
> > drivers/net/wireguard/timers.c:215
The line of hlist_add_head that it's hitting is:
static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
{
struct hlist_node *first = h->first;
WRITE_ONCE(n->next, first);
if (first)
So that means it's the dereferencing of h that's a problem. That comes from:
static void enqueue_timer(struct timer_base *base, struct timer_list *timer,
unsigned int idx, unsigned long bucket_expiry)
{
hlist_add_head(>entry, base->vectors + idx);
That means it concerns base->vectors + idx, not the timer_list object
that wireguard manages. That's confusing. Could that imply that the
bug is in freeing a previous timer without removing it from the timer
lists, so that it winds up being in base->vectors?
The allocation and deallocation backtrace is confusing
> > alloc_netdev_mqs+0x5c/0x3bc net/core/dev.c:10546
> > rtnl_create_link+0xc8/0x2b0 net/core/rtnetlink.c:3171
> > __rtnl_newlink+0x5bc/0x800 net/core/rtnetlink.c:3433
This suggests it's part of the `ip link add wg0 type wireguard` nelink
call, during it's allocation of the netdevice's private area. For
this, the wg_device struct is used. It has no timer_list structures in
it!
Similarly,
> > netdev_freemem+0x18/0x2c net/core/dev.c:10500
> > netdev_release+0x30/0x44 net/core/net-sysfs.c:1828
> > device_release+0x34/0x90 drivers/base/core.c:1980
That smells like `ip link del wg0 type wireguard`. But again,
wg_device doesn't have any timer_lists in it.
So what's happening here exactly? I'm not really sure yet...
It'd be nice to have a reproducer.
Jason
Re: KASAN: invalid-access Write in enqueue_timer
Adding Jason and Ard. It may be a use-after-free in the wireguard driver. Catalin On Mon, Feb 15, 2021 at 04:06:16PM -0800, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit:f40ddce8 Linux 5.11 > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1395db28d0 > kernel config: https://syzkaller.appspot.com/x/.config?x=494a8e2d9bf09818 > dashboard link: https://syzkaller.appspot.com/bug?extid=95c862be69e37145543f > userspace arch: arm64 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+95c862be69e371455...@syzkaller.appspotmail.com > > == > BUG: KASAN: invalid-access in hlist_add_head include/linux/list.h:883 [inline] > BUG: KASAN: invalid-access in enqueue_timer+0x18/0xc0 kernel/time/timer.c:581 > Write at addr f4ff275dcda0 by task kworker/u4:6/2919 > Pointer tag: [f4], memory tag: [fe] > > CPU: 1 PID: 2919 Comm: kworker/u4:6 Not tainted 5.11.0-syzkaller #0 > Hardware name: linux,dummy-virt (DT) > Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker > Call trace: > dump_backtrace+0x0/0x1b0 arch/arm64/kernel/stacktrace.c:117 > show_stack+0x18/0x70 arch/arm64/kernel/stacktrace.c:196 > __dump_stack lib/dump_stack.c:79 [inline] > dump_stack+0xd0/0x12c lib/dump_stack.c:120 > print_address_description+0x70/0x29c mm/kasan/report.c:230 > __kasan_report mm/kasan/report.c:396 [inline] > kasan_report+0x134/0x380 mm/kasan/report.c:413 > report_tag_fault arch/arm64/mm/fault.c:311 [inline] > do_tag_recovery arch/arm64/mm/fault.c:325 [inline] > __do_kernel_fault+0x178/0x1bc arch/arm64/mm/fault.c:369 > do_bad_area arch/arm64/mm/fault.c:462 [inline] > do_tag_check_fault+0x74/0x90 arch/arm64/mm/fault.c:717 > do_mem_abort+0x44/0xbc arch/arm64/mm/fault.c:793 > el1_abort+0x40/0x6c arch/arm64/kernel/entry-common.c:118 > el1_sync_handler+0xac/0xd0 arch/arm64/kernel/entry-common.c:209 > el1_sync+0x70/0x100 arch/arm64/kernel/entry.S:656 > hlist_add_head include/linux/list.h:883 [inline] > enqueue_timer+0x18/0xc0 kernel/time/timer.c:581 > mod_timer+0x14/0x20 kernel/time/timer.c:1106 > mod_peer_timer drivers/net/wireguard/timers.c:37 [inline] > wg_timers_any_authenticated_packet_traversal+0x68/0x90 > drivers/net/wireguard/timers.c:215 > wg_packet_send_handshake_initiation+0xa8/0xe0 drivers/net/wireguard/send.c:36 > wg_packet_handshake_send_worker+0x1c/0x34 drivers/net/wireguard/send.c:51 > process_one_work+0x1d8/0x360 kernel/workqueue.c:2275 > worker_thread+0x70/0x434 kernel/workqueue.c:2421 > kthread+0x174/0x180 kernel/kthread.c:292 > ret_from_fork+0x10/0x34 arch/arm64/kernel/entry.S:958 > > Allocated by task 6247: > stack_trace_save+0x50/0x80 kernel/stacktrace.c:121 > kasan_save_stack+0x28/0x60 mm/kasan/common.c:38 > kasan_set_track mm/kasan/common.c:46 [inline] > set_alloc_info mm/kasan/common.c:401 [inline] > kasan_kmalloc+0xe8/0x160 mm/kasan/common.c:429 > __kasan_kmalloc+0x14/0x20 mm/kasan/common.c:443 > kasan_kmalloc include/linux/kasan.h:219 [inline] > __kmalloc_node+0x1d0/0x3ac mm/slub.c:4033 > kmalloc_node include/linux/slab.h:575 [inline] > kvmalloc_node+0x40/0xe0 mm/util.c:587 > kvmalloc include/linux/mm.h:781 [inline] > kvzalloc include/linux/mm.h:789 [inline] > alloc_netdev_mqs+0x5c/0x3bc net/core/dev.c:10546 > rtnl_create_link+0xc8/0x2b0 net/core/rtnetlink.c:3171 > __rtnl_newlink+0x5bc/0x800 net/core/rtnetlink.c:3433 > rtnl_newlink+0x70/0xa0 net/core/rtnetlink.c:3491 > rtnetlink_rcv_msg+0x118/0x334 net/core/rtnetlink.c:5553 > netlink_rcv_skb+0x5c/0x130 net/netlink/af_netlink.c:2494 > rtnetlink_rcv+0x18/0x2c net/core/rtnetlink.c:5571 > netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] > netlink_unicast+0x25c/0x320 net/netlink/af_netlink.c:1330 > netlink_sendmsg+0x1d4/0x3e4 net/netlink/af_netlink.c:1919 > sock_sendmsg_nosec net/socket.c:652 [inline] > sock_sendmsg+0x54/0x60 net/socket.c:672 > __sys_sendto+0x118/0x14c net/socket.c:1975 > __do_sys_sendto net/socket.c:1987 [inline] > __se_sys_sendto net/socket.c:1983 [inline] > __arm64_sys_sendto+0x2c/0x40 net/socket.c:1983 > __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] > invoke_syscall arch/arm64/kernel/syscall.c:49 [inline] > el0_svc_common.constprop.0+0x74/0x190 arch/arm64/kernel/syscall.c:159 > do_el0_svc+0x74/0x90 arch/arm64/kernel/syscall.c:198 > el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365 > el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:381 > el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699 > > Freed by task 24: > stack_trace_save+0x50/0x80 kernel/stacktrace.c:121 > kasan_save_stack+0x28/0x60 mm/kasan/common.c:38 > kasan_set_track+0x28/0x40 mm/kasan/common.c:46 > kasan_set_free_info+0x20/0x30 mm/kasan/hw_tags.c:174 > kasan_slab_free.constprop.0+0x184/0x1c0
KASAN: invalid-access Write in enqueue_timer
Hello, syzbot found the following issue on: HEAD commit:f40ddce8 Linux 5.11 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1395db28d0 kernel config: https://syzkaller.appspot.com/x/.config?x=494a8e2d9bf09818 dashboard link: https://syzkaller.appspot.com/bug?extid=95c862be69e37145543f userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+95c862be69e371455...@syzkaller.appspotmail.com == BUG: KASAN: invalid-access in hlist_add_head include/linux/list.h:883 [inline] BUG: KASAN: invalid-access in enqueue_timer+0x18/0xc0 kernel/time/timer.c:581 Write at addr f4ff275dcda0 by task kworker/u4:6/2919 Pointer tag: [f4], memory tag: [fe] CPU: 1 PID: 2919 Comm: kworker/u4:6 Not tainted 5.11.0-syzkaller #0 Hardware name: linux,dummy-virt (DT) Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker Call trace: dump_backtrace+0x0/0x1b0 arch/arm64/kernel/stacktrace.c:117 show_stack+0x18/0x70 arch/arm64/kernel/stacktrace.c:196 __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0xd0/0x12c lib/dump_stack.c:120 print_address_description+0x70/0x29c mm/kasan/report.c:230 __kasan_report mm/kasan/report.c:396 [inline] kasan_report+0x134/0x380 mm/kasan/report.c:413 report_tag_fault arch/arm64/mm/fault.c:311 [inline] do_tag_recovery arch/arm64/mm/fault.c:325 [inline] __do_kernel_fault+0x178/0x1bc arch/arm64/mm/fault.c:369 do_bad_area arch/arm64/mm/fault.c:462 [inline] do_tag_check_fault+0x74/0x90 arch/arm64/mm/fault.c:717 do_mem_abort+0x44/0xbc arch/arm64/mm/fault.c:793 el1_abort+0x40/0x6c arch/arm64/kernel/entry-common.c:118 el1_sync_handler+0xac/0xd0 arch/arm64/kernel/entry-common.c:209 el1_sync+0x70/0x100 arch/arm64/kernel/entry.S:656 hlist_add_head include/linux/list.h:883 [inline] enqueue_timer+0x18/0xc0 kernel/time/timer.c:581 mod_timer+0x14/0x20 kernel/time/timer.c:1106 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline] wg_timers_any_authenticated_packet_traversal+0x68/0x90 drivers/net/wireguard/timers.c:215 wg_packet_send_handshake_initiation+0xa8/0xe0 drivers/net/wireguard/send.c:36 wg_packet_handshake_send_worker+0x1c/0x34 drivers/net/wireguard/send.c:51 process_one_work+0x1d8/0x360 kernel/workqueue.c:2275 worker_thread+0x70/0x434 kernel/workqueue.c:2421 kthread+0x174/0x180 kernel/kthread.c:292 ret_from_fork+0x10/0x34 arch/arm64/kernel/entry.S:958 Allocated by task 6247: stack_trace_save+0x50/0x80 kernel/stacktrace.c:121 kasan_save_stack+0x28/0x60 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:401 [inline] kasan_kmalloc+0xe8/0x160 mm/kasan/common.c:429 __kasan_kmalloc+0x14/0x20 mm/kasan/common.c:443 kasan_kmalloc include/linux/kasan.h:219 [inline] __kmalloc_node+0x1d0/0x3ac mm/slub.c:4033 kmalloc_node include/linux/slab.h:575 [inline] kvmalloc_node+0x40/0xe0 mm/util.c:587 kvmalloc include/linux/mm.h:781 [inline] kvzalloc include/linux/mm.h:789 [inline] alloc_netdev_mqs+0x5c/0x3bc net/core/dev.c:10546 rtnl_create_link+0xc8/0x2b0 net/core/rtnetlink.c:3171 __rtnl_newlink+0x5bc/0x800 net/core/rtnetlink.c:3433 rtnl_newlink+0x70/0xa0 net/core/rtnetlink.c:3491 rtnetlink_rcv_msg+0x118/0x334 net/core/rtnetlink.c:5553 netlink_rcv_skb+0x5c/0x130 net/netlink/af_netlink.c:2494 rtnetlink_rcv+0x18/0x2c net/core/rtnetlink.c:5571 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x25c/0x320 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x1d4/0x3e4 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0x54/0x60 net/socket.c:672 __sys_sendto+0x118/0x14c net/socket.c:1975 __do_sys_sendto net/socket.c:1987 [inline] __se_sys_sendto net/socket.c:1983 [inline] __arm64_sys_sendto+0x2c/0x40 net/socket.c:1983 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall arch/arm64/kernel/syscall.c:49 [inline] el0_svc_common.constprop.0+0x74/0x190 arch/arm64/kernel/syscall.c:159 do_el0_svc+0x74/0x90 arch/arm64/kernel/syscall.c:198 el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:381 el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699 Freed by task 24: stack_trace_save+0x50/0x80 kernel/stacktrace.c:121 kasan_save_stack+0x28/0x60 mm/kasan/common.c:38 kasan_set_track+0x28/0x40 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/hw_tags.c:174 kasan_slab_free.constprop.0+0x184/0x1c0 mm/kasan/common.c:362 __kasan_slab_free+0x10/0x20 mm/kasan/common.c:369 kasan_slab_free include/linux/kasan.h:192 [inline] slab_free_hook mm/slub.c:1547 [inline] slab_free_freelist_hook+0x98/0x18c mm/slub.c:1580 slab_free mm/slub.c:3143 [inline] kfree+0x324/0x4a0 mm/slub.c:4139 kvfree+0x3c/0x50 mm/util.c:616 netdev_freemem+0x18/0x2c
