So got my skylake machine re-compiled with gcc-5 and got this.
Should I keep reporting these, or is everyone fuzzing now so you're all
hitting them too?
[ 911.507365] ==================================================================
[ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
[ 911.523912] Read of size 8 by task perf_fuzzer/20662
[ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
[ 911.534619] CPU: 7 PID: 20662 Comm: perf_fuzzer Tainted: G L 4.9.0-rc5+ #12
[ 911.534620] Hardware name: LENOVO 10FY0017US/SKYBAY, BIOS FWKT53A 06/06/2016
[ 911.534622] ffff8801efd2f970 ffffffffb0f17c88 ffff8801efd2fa08 ffffffffb14ad058
[ 911.534624] ffff8801efd2f9f8 ffffffffb0d0a9f3 1ffff1003dfa5f38 ffff8801efd2fc38
[ 911.534627] ffff8801f12ca100 0000000000000297 ffff8801efd2fc38 ffff8801efd2fa38
[ 911.534629] Call Trace:
[ 911.534633] [<ffffffffb0f17c88>] dump_stack+0x63/0x8b
[ 911.534636] [<ffffffffb0d0a9f3>] kasan_report_error+0x493/0x4c0
[ 911.534638] [<ffffffffb0f27a43>] ? simple_strtoull+0x93/0xe0
[ 911.534640] [<ffffffffb0d0b038>] kasan_report+0x58/0x60
[ 911.534642] [<ffffffffb0f31008>] ? match_token+0x268/0x310
[ 911.534644] [<ffffffffb0d0949e>] __asan_load8+0x5e/0x70
[ 911.534646] [<ffffffffb0f31008>] match_token+0x268/0x310
[ 911.534649] [<ffffffffb0d058f8>] ? kmem_cache_alloc_node_trace+0x108/0x5a0
[ 911.534651] [<ffffffffb0f30da0>] ? match_wildcard+0x130/0x130
[ 911.534653] [<ffffffffb0cbb4b5>] ? wp_page_copy+0x6f5/0xb80
[ 911.534656] [<ffffffffb0c49668>] ? perf_event_set_addr_filter+0x1f8/0x630
[ 911.534658] [<ffffffffb0c496bb>] perf_event_set_addr_filter+0x24b/0x630
[ 911.534660] [<ffffffffb0c49470>] ? perf_pin_task_context+0xd0/0xd0
[ 911.534663] [<ffffffffb0d09976>] ? kasan_unpoison_shadow+0x36/0x50
[ 911.534665] [<ffffffffb0d09add>] ? kasan_kmalloc+0xad/0xe0
[ 911.534667] [<ffffffffb0d06a0b>] ? __kmalloc_track_caller+0x10b/0x580
[ 911.534669] [<ffffffffb0cbccd0>] ? vm_normal_page+0x130/0x130
[ 911.534671] [<ffffffffb0c9fe06>] ? strndup_user+0x46/0x70
[ 911.534673] [<ffffffffb0d097d4>] ? kasan_check_write+0x14/0x20
[ 911.534675] [<ffffffffb0c9fd8d>] ? memdup_user+0x4d/0x80
[ 911.534677] [<ffffffffb0c56a7a>] perf_ioctl+0x5fa/0x810
[ 911.534680] [<ffffffffb0c56480>] ? SYSC_perf_event_open+0x11e0/0x11e0
[ 911.534682] [<ffffffffb0cc1472>] ? handle_mm_fault+0x602/0x1c30
[ 911.534684] [<ffffffffb0d589bb>] do_vfs_ioctl+0x14b/0x920
[ 911.534686] [<ffffffffb0d58870>] ? ioctl_preallocate+0x160/0x160
[ 911.534689] [<ffffffffb0e36be3>] ? security_file_permission+0xd3/0x100
[ 911.534692] [<ffffffffb0c59af8>] ? __perf_sw_event+0x98/0xc0
[ 911.534694] [<ffffffffb0aa0639>] ? __do_page_fault+0x579/0x650
[ 911.534696] [<ffffffffb0d59209>] SyS_ioctl+0x79/0x90
[ 911.534699] [<ffffffffb13f493b>] entry_SYSCALL_64_fastpath+0x1e/0xad
[ 911.534700] Memory state around the buggy address:
[ 911.539563] ffffffffb14acf00: fa fa fa fa 06 fa fa fa fa fa fa fa 06 fa fa fa
[ 911.546942] ffffffffb14acf80: fa fa fa fa 03 fa fa fa fa fa fa fa 00 00 00 00
[ 911.554269] >ffffffffb14ad000: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
[ 911.561598] ^
[ 911.567800] ffffffffb14ad080: 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa
[ 911.575138] ffffffffb14ad100: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
[ 911.582492] ==================================================================
Adding Alexander Shishkin as this seems to be an issue with the address
range filtering code.
On Thu, 17 Nov 2016, Vince Weaver wrote:
>
> So got my skylake machine re-compiled with gcc-5 and got this.
>
> Should I keep reporting these, or is everyone fuzzing now so you're all
> hitting them too?
>
> [ 911.507365] ==================================================================
> [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
> [ 911.523912] Read of size 8 by task perf_fuzzer/20662
> [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
> [ 911.534619] CPU: 7 PID: 20662 Comm: perf_fuzzer Tainted: G L 4.9.0-rc5+ #12
> [ 911.534620] Hardware name: LENOVO 10FY0017US/SKYBAY, BIOS FWKT53A 06/06/2016
> [ 911.534622] ffff8801efd2f970 ffffffffb0f17c88 ffff8801efd2fa08 ffffffffb14ad058
> [ 911.534624] ffff8801efd2f9f8 ffffffffb0d0a9f3 1ffff1003dfa5f38 ffff8801efd2fc38
> [ 911.534627] ffff8801f12ca100 0000000000000297 ffff8801efd2fc38 ffff8801efd2fa38
> [ 911.534629] Call Trace:
> [ 911.534633] [<ffffffffb0f17c88>] dump_stack+0x63/0x8b
> [ 911.534636] [<ffffffffb0d0a9f3>] kasan_report_error+0x493/0x4c0
> [ 911.534638] [<ffffffffb0f27a43>] ? simple_strtoull+0x93/0xe0
> [ 911.534640] [<ffffffffb0d0b038>] kasan_report+0x58/0x60
> [ 911.534642] [<ffffffffb0f31008>] ? match_token+0x268/0x310
> [ 911.534644] [<ffffffffb0d0949e>] __asan_load8+0x5e/0x70
> [ 911.534646] [<ffffffffb0f31008>] match_token+0x268/0x310
> [ 911.534649] [<ffffffffb0d058f8>] ? kmem_cache_alloc_node_trace+0x108/0x5a0
> [ 911.534651] [<ffffffffb0f30da0>] ? match_wildcard+0x130/0x130
> [ 911.534653] [<ffffffffb0cbb4b5>] ? wp_page_copy+0x6f5/0xb80
> [ 911.534656] [<ffffffffb0c49668>] ? perf_event_set_addr_filter+0x1f8/0x630
> [ 911.534658] [<ffffffffb0c496bb>] perf_event_set_addr_filter+0x24b/0x630
> [ 911.534660] [<ffffffffb0c49470>] ? perf_pin_task_context+0xd0/0xd0
> [ 911.534663] [<ffffffffb0d09976>] ? kasan_unpoison_shadow+0x36/0x50
> [ 911.534665] [<ffffffffb0d09add>] ? kasan_kmalloc+0xad/0xe0
> [ 911.534667] [<ffffffffb0d06a0b>] ? __kmalloc_track_caller+0x10b/0x580
> [ 911.534669] [<ffffffffb0cbccd0>] ? vm_normal_page+0x130/0x130
> [ 911.534671] [<ffffffffb0c9fe06>] ? strndup_user+0x46/0x70
> [ 911.534673] [<ffffffffb0d097d4>] ? kasan_check_write+0x14/0x20
> [ 911.534675] [<ffffffffb0c9fd8d>] ? memdup_user+0x4d/0x80
> [ 911.534677] [<ffffffffb0c56a7a>] perf_ioctl+0x5fa/0x810
> [ 911.534680] [<ffffffffb0c56480>] ? SYSC_perf_event_open+0x11e0/0x11e0
> [ 911.534682] [<ffffffffb0cc1472>] ? handle_mm_fault+0x602/0x1c30
> [ 911.534684] [<ffffffffb0d589bb>] do_vfs_ioctl+0x14b/0x920
> [ 911.534686] [<ffffffffb0d58870>] ? ioctl_preallocate+0x160/0x160
> [ 911.534689] [<ffffffffb0e36be3>] ? security_file_permission+0xd3/0x100
> [ 911.534692] [<ffffffffb0c59af8>] ? __perf_sw_event+0x98/0xc0
> [ 911.534694] [<ffffffffb0aa0639>] ? __do_page_fault+0x579/0x650
> [ 911.534696] [<ffffffffb0d59209>] SyS_ioctl+0x79/0x90
> [ 911.534699] [<ffffffffb13f493b>] entry_SYSCALL_64_fastpath+0x1e/0xad
> [ 911.534700] Memory state around the buggy address:
> [ 911.539563] ffffffffb14acf00: fa fa fa fa 06 fa fa fa fa fa fa fa 06 fa fa fa
> [ 911.546942] ffffffffb14acf80: fa fa fa fa 03 fa fa fa fa fa fa fa 00 00 00 00
> [ 911.554269] >ffffffffb14ad000: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
> [ 911.561598] ^
> [ 911.567800] ffffffffb14ad080: 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa
> [ 911.575138] ffffffffb14ad100: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
> [ 911.582492] ==================================================================
>
>
>
>
>
>
>
On Thu, 17 Nov 2016, Vince Weaver wrote:
> >
> > [ 911.507365] ==================================================================
> > [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
> > [ 911.523912] Read of size 8 by task perf_fuzzer/20662
> > [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
> > [ 911.534619] CPU: 7 PID: 20662 Comm: perf_fuzzer Tainted: G L 4.9.0-rc5+ #12
> > [ 911.534620] Hardware name: LENOVO 10FY0017US/SKYBAY, BIOS FWKT53A 06/06/2016
> > [ 911.534622] ffff8801efd2f970 ffffffffb0f17c88 ffff8801efd2fa08 ffffffffb14ad058
> > [ 911.534624] ffff8801efd2f9f8 ffffffffb0d0a9f3 1ffff1003dfa5f38 ffff8801efd2fc38
> > [ 911.534627] ffff8801f12ca100 0000000000000297 ffff8801efd2fc38 ffff8801efd2fa38
OK, this one is easily reproducible and from what I can tell it is caused
by calling
ioctl(PERF_EVENT_IOC_SET_FILTER)
where the filter trying to be set is
(((to&733)&&common_type&605)||common_flags<386922879890793102)
the ioctl itself fails due to EINVAL
I'll see if I can come up with a working small test case.
Vince
Vince Weaver <[email protected]> writes:
Adding Alex since it seems to be related to PT code.
> So got my skylake machine re-compiled with gcc-5 and got this.
>
> Should I keep reporting these, or is everyone fuzzing now so you're all
> hitting them too?
>
> [ 911.507365] ==================================================================
> [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
> [ 911.523912] Read of size 8 by task perf_fuzzer/20662
> [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
> [ 911.534619] CPU: 7 PID: 20662 Comm: perf_fuzzer Tainted: G L 4.9.0-rc5+ #12
> [ 911.534620] Hardware name: LENOVO 10FY0017US/SKYBAY, BIOS FWKT53A 06/06/2016
> [ 911.534622] ffff8801efd2f970 ffffffffb0f17c88 ffff8801efd2fa08 ffffffffb14ad058
> [ 911.534624] ffff8801efd2f9f8 ffffffffb0d0a9f3 1ffff1003dfa5f38 ffff8801efd2fc38
> [ 911.534627] ffff8801f12ca100 0000000000000297 ffff8801efd2fc38 ffff8801efd2fa38
> [ 911.534629] Call Trace:
> [ 911.534633] [<ffffffffb0f17c88>] dump_stack+0x63/0x8b
> [ 911.534636] [<ffffffffb0d0a9f3>] kasan_report_error+0x493/0x4c0
> [ 911.534638] [<ffffffffb0f27a43>] ? simple_strtoull+0x93/0xe0
> [ 911.534640] [<ffffffffb0d0b038>] kasan_report+0x58/0x60
> [ 911.534642] [<ffffffffb0f31008>] ? match_token+0x268/0x310
> [ 911.534644] [<ffffffffb0d0949e>] __asan_load8+0x5e/0x70
> [ 911.534646] [<ffffffffb0f31008>] match_token+0x268/0x310
> [ 911.534649] [<ffffffffb0d058f8>] ? kmem_cache_alloc_node_trace+0x108/0x5a0
> [ 911.534651] [<ffffffffb0f30da0>] ? match_wildcard+0x130/0x130
> [ 911.534653] [<ffffffffb0cbb4b5>] ? wp_page_copy+0x6f5/0xb80
> [ 911.534656] [<ffffffffb0c49668>] ? perf_event_set_addr_filter+0x1f8/0x630
> [ 911.534658] [<ffffffffb0c496bb>] perf_event_set_addr_filter+0x24b/0x630
> [ 911.534660] [<ffffffffb0c49470>] ? perf_pin_task_context+0xd0/0xd0
> [ 911.534663] [<ffffffffb0d09976>] ? kasan_unpoison_shadow+0x36/0x50
> [ 911.534665] [<ffffffffb0d09add>] ? kasan_kmalloc+0xad/0xe0
> [ 911.534667] [<ffffffffb0d06a0b>] ? __kmalloc_track_caller+0x10b/0x580
> [ 911.534669] [<ffffffffb0cbccd0>] ? vm_normal_page+0x130/0x130
> [ 911.534671] [<ffffffffb0c9fe06>] ? strndup_user+0x46/0x70
> [ 911.534673] [<ffffffffb0d097d4>] ? kasan_check_write+0x14/0x20
> [ 911.534675] [<ffffffffb0c9fd8d>] ? memdup_user+0x4d/0x80
> [ 911.534677] [<ffffffffb0c56a7a>] perf_ioctl+0x5fa/0x810
> [ 911.534680] [<ffffffffb0c56480>] ? SYSC_perf_event_open+0x11e0/0x11e0
> [ 911.534682] [<ffffffffb0cc1472>] ? handle_mm_fault+0x602/0x1c30
> [ 911.534684] [<ffffffffb0d589bb>] do_vfs_ioctl+0x14b/0x920
> [ 911.534686] [<ffffffffb0d58870>] ? ioctl_preallocate+0x160/0x160
> [ 911.534689] [<ffffffffb0e36be3>] ? security_file_permission+0xd3/0x100
> [ 911.534692] [<ffffffffb0c59af8>] ? __perf_sw_event+0x98/0xc0
> [ 911.534694] [<ffffffffb0aa0639>] ? __do_page_fault+0x579/0x650
> [ 911.534696] [<ffffffffb0d59209>] SyS_ioctl+0x79/0x90
> [ 911.534699] [<ffffffffb13f493b>] entry_SYSCALL_64_fastpath+0x1e/0xad
> [ 911.534700] Memory state around the buggy address:
> [ 911.539563] ffffffffb14acf00: fa fa fa fa 06 fa fa fa fa fa fa fa 06 fa fa fa
> [ 911.546942] ffffffffb14acf80: fa fa fa fa 03 fa fa fa fa fa fa fa 00 00 00 00
> [ 911.554269] >ffffffffb14ad000: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
> [ 911.561598] ^
> [ 911.567800] ffffffffb14ad080: 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa
> [ 911.575138] ffffffffb14ad100: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
> [ 911.582492] ==================================================================
On Thu, 17 Nov 2016, Vince Weaver wrote:
> On Thu, 17 Nov 2016, Vince Weaver wrote:
> > >
> > > [ 911.507365] ==================================================================
> > > [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
> > > [ 911.523912] Read of size 8 by task perf_fuzzer/20662
> > > [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
I managed to create a short reproducer that reliably causes the issue on
my skylake test machine.
/* simplified perf_fuzzer test case */
/* that triggers BUG: KASAN: global-out-of-bounds in match_token+0x288 */
/* on a skylake machine running Linux 4.9-rc5 */
/* by Vince Weaver <vincent.weaver _at_ maine.edu> */
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <linux/perf_event.h>
int perf_event_open(struct perf_event_attr *hw_event_uptr,
pid_t pid, int cpu, int group_fd, unsigned long flags) {
return syscall(__NR_perf_event_open,hw_event_uptr, pid, cpu,
group_fd, flags);
}
int main(int argc, char **argv) {
int fd7;
struct perf_event_attr pe7;
char filter[]="(((to&733)&&common_type&605)||common_flags<386922879890793102)";
memset(&pe7,0,sizeof(struct perf_event_attr));
pe7.type=7; /* intel_pt */
pe7.size=72;
pe7.config=0x200ULL; /* bit 10 = tsc */
pe7.read_format=PERF_FORMAT_TOTAL_TIME_ENABLED; /* 1 */
pe7.disabled=1;
pe7.pinned=1;
pe7.comm_exec=1;
fd7=perf_event_open(&pe7,
0, /* current thread */
0, /* Only cpu 0 */
-1, /* group leader */
PERF_FLAG_FD_NO_GROUP /*1*/ );
ioctl(fd7, PERF_EVENT_IOC_SET_FILTER , &filter);
return 0;
}
* Vince Weaver <[email protected]> wrote:
> On Thu, 17 Nov 2016, Vince Weaver wrote:
>
> > On Thu, 17 Nov 2016, Vince Weaver wrote:
> > > >
> > > > [ 911.507365] ==================================================================
> > > > [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
> > > > [ 911.523912] Read of size 8 by task perf_fuzzer/20662
> > > > [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
>
> I managed to create a short reproducer that reliably causes the issue on
> my skylake test machine.
Awesome, thanks a lot Vince!
Ingo
Vince Weaver <[email protected]> writes:
> On Thu, 17 Nov 2016, Vince Weaver wrote:
>
>> On Thu, 17 Nov 2016, Vince Weaver wrote:
>> > >
>> > > [ 911.507365] ==================================================================
>> > > [ 911.514824] BUG: KASAN: global-out-of-bounds in match_token+0x268/0x310 at addr ffffffffb14ad058
>> > > [ 911.523912] Read of size 8 by task perf_fuzzer/20662
>> > > [ 911.528945] Address belongs to variable if_tokens+0x78/0xa0
>
> I managed to create a short reproducer that reliably causes the issue on
> my skylake test machine.
Thanks a bunch, and ugh, this is embarrassing.
>From 139306c3bcf7abf49c51a8e56131aaae51222594 Mon Sep 17 00:00:00 2001
From: Alexander Shishkin <[email protected]>
Date: Fri, 18 Nov 2016 13:24:55 +0200
Subject: [PATCH] perf: Fix address filter parser
The token table passed into match_token() must be null-terminated, which
it currently is not in the perf's address filter string parser, as caught
by Vince's perf_fuzzer and KASAN. It doesn't blow up otherwise because of
the alignment padding of the table to the next element in the .rodata,
which is luck.
Fixing by adding a null-terminator to the token table.
Signed-off-by: Alexander Shishkin <[email protected]>
Fixes: 375637bc524 ("perf/core: Introduce address range filtering")
Reported-by: Vince Weaver <[email protected]>
Cc: [email protected] # v4.7+
---
kernel/events/core.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index c6e47e97b3..63c72dee71 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8012,6 +8012,7 @@ static void perf_event_addr_filters_apply(struct perf_event *event)
* if <size> is not specified, the range is treated as a single address.
*/
enum {
+ IF_ACT_NONE = -1,
IF_ACT_FILTER,
IF_ACT_START,
IF_ACT_STOP,
@@ -8035,6 +8036,7 @@ static const match_table_t if_tokens = {
{ IF_SRC_KERNEL, "%u/%u" },
{ IF_SRC_FILEADDR, "%u@%s" },
{ IF_SRC_KERNELADDR, "%u" },
+ { IF_ACT_NONE, NULL },
};
/*
--
2.10.2
On Fri, 18 Nov 2016, Alexander Shishkin wrote:
> From 139306c3bcf7abf49c51a8e56131aaae51222594 Mon Sep 17 00:00:00 2001
> From: Alexander Shishkin <[email protected]>
> Date: Fri, 18 Nov 2016 13:24:55 +0200
> Subject: [PATCH] perf: Fix address filter parser
>
> The token table passed into match_token() must be null-terminated, which
> it currently is not in the perf's address filter string parser, as caught
> by Vince's perf_fuzzer and KASAN. It doesn't blow up otherwise because of
> the alignment padding of the table to the next element in the .rodata,
> which is luck.
I can confirm that with this patch applied I no longer get the
token-parsing KASAN messages.
This is even after I enhanced the perf_fuzzer to generate more realistic
address-filters.
As an aside, is there any better documentation on what a "proper" address
filter looks like? In kernel/events/core.c it says
* ACTION RANGE_SPEC
* where ACTION is one of the
* * "filter": limit the trace to this region
* * "start": start tracing from this address
* * "stop": stop tracing at this address/region;
* RANGE_SPEC is
* * for kernel addresses: <start address>[/<size>]
* * for object files: <start address>[/<size>]@</path/to/object/file>
Does each action always get a range?
Are the ranges hex? decimal? can they have a leading 0x?
Are the sizes hex? decimal?
What's the path to object file for? What kind of object file?
Vince
Commit-ID: e96271f3ed7e702fa36dd0605c0c5b5f065af816
Gitweb: http://git.kernel.org/tip/e96271f3ed7e702fa36dd0605c0c5b5f065af816
Author: Alexander Shishkin <[email protected]>
AuthorDate: Fri, 18 Nov 2016 13:38:43 +0200
Committer: Ingo Molnar <[email protected]>
CommitDate: Mon, 21 Nov 2016 11:28:36 +0100
perf/core: Fix address filter parser
The token table passed into match_token() must be null-terminated, which
it currently is not in the perf's address filter string parser, as caught
by Vince's perf_fuzzer and KASAN.
It doesn't blow up otherwise because of the alignment padding of the table
to the next element in the .rodata, which is luck.
Fixing by adding a null-terminator to the token table.
Reported-by: Vince Weaver <[email protected]>
Tested-by: Vince Weaver <[email protected]>
Signed-off-by: Alexander Shishkin <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected] # v4.7+
Fixes: 375637bc524 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/events/core.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index ff230bb..6ee1feb 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8029,6 +8029,7 @@ restart:
* if <size> is not specified, the range is treated as a single address.
*/
enum {
+ IF_ACT_NONE = -1,
IF_ACT_FILTER,
IF_ACT_START,
IF_ACT_STOP,
@@ -8052,6 +8053,7 @@ static const match_table_t if_tokens = {
{ IF_SRC_KERNEL, "%u/%u" },
{ IF_SRC_FILEADDR, "%u@%s" },
{ IF_SRC_KERNELADDR, "%u" },
+ { IF_ACT_NONE, NULL },
};
/*