In the fixes commit, removing SIGKILL from each thread signal mask
and executing "goto fatal" directly will skip the call to
"trace_signal_deliver". At this point, the delivery tracking of the SIGKILL
signal will be inaccurate.
Therefore, we need to add trace_signal_deliver before "goto fatal"
after executing sigdelset.
Note: The action[SIGKILL] must be SIG_DFL, and SEND_SIG_NOINFO matches
the fact that SIGKILL doesn't have any info.
Acked-by: Christian Brauner <[email protected]>
Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT")
Signed-off-by: Zhenliang Wei <[email protected]>
---
kernel/signal.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/signal.c b/kernel/signal.c
index 227ba170298e..0f69ada376ef 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
if (signal_group_exit(signal)) {
ksig->info.si_signo = signr = SIGKILL;
sigdelset(¤t->pending.signal, SIGKILL);
+ trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
recalc_sigpending();
goto fatal;
}
--
2.14.1.windows.1
On 04/22, Zhenliang Wei wrote:
>
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
> if (signal_group_exit(signal)) {
> ksig->info.si_signo = signr = SIGKILL;
> sigdelset(¤t->pending.signal, SIGKILL);
> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
> recalc_sigpending();
> goto fatal;
> }
Reviewed-by: Oleg Nesterov <[email protected]>
On Mon, Apr 22, 2019 at 10:59:50PM +0800, Zhenliang Wei wrote:
> In the fixes commit, removing SIGKILL from each thread signal mask
> and executing "goto fatal" directly will skip the call to
> "trace_signal_deliver". At this point, the delivery tracking of the SIGKILL
> signal will be inaccurate.
>
> Therefore, we need to add trace_signal_deliver before "goto fatal"
> after executing sigdelset.
>
> Note: The action[SIGKILL] must be SIG_DFL, and SEND_SIG_NOINFO matches
> the fact that SIGKILL doesn't have any info.
>
> Acked-by: Christian Brauner <[email protected]>
> Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT")
> Signed-off-by: Zhenliang Wei <[email protected]>
> ---
> kernel/signal.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 227ba170298e..0f69ada376ef 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
> if (signal_group_exit(signal)) {
> ksig->info.si_signo = signr = SIGKILL;
> sigdelset(¤t->pending.signal, SIGKILL);
> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
> recalc_sigpending();
> goto fatal;
> }
> --
> 2.14.1.windows.1
>
>
<formletter>
This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.
</formletter>
Hi Zhenliang,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.1-rc6 next-20190418]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Zhenliang-Wei/signal-trace_signal_deliver-when-signal_group_exit/20190423-062107
config: i386-randconfig-x010-201916 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <[email protected]>
All error/warnings (new ones prefixed by >>):
In file included from arch/x86/include/uapi/asm/signal.h:94:0,
from arch/x86/include/asm/signal.h:36,
from include/uapi/linux/signal.h:5,
from include/linux/signal_types.h:10,
from include/linux/sched.h:28,
from include/linux/sched/mm.h:7,
from kernel/signal.c:16:
kernel/signal.c: In function 'get_signal':
>> include/uapi/asm-generic/signal-defs.h:24:17: error: passing argument 3 of 'trace_signal_deliver' from incompatible pointer type [-Werror=incompatible-pointer-types]
#define SIG_DFL ((__force __sighandler_t)0) /* default signal handling */
^
>> kernel/signal.c:2444:50: note: in expansion of macro 'SIG_DFL'
trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
^~~~~~~
In file included from include/trace/syscall.h:5:0,
from include/linux/syscalls.h:86,
from kernel/signal.c:29:
include/linux/tracepoint.h:235:21: note: expected 'struct k_sigaction *' but argument is of type 'void (*)(int)'
static inline void trace_##name(proto) \
^
include/linux/tracepoint.h:398:2: note: in expansion of macro '__DECLARE_TRACE'
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \
^~~~~~~~~~~~~~~
include/linux/tracepoint.h:534:2: note: in expansion of macro 'DECLARE_TRACE'
DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
^~~~~~~~~~~~~
>> include/trace/events/signal.h:96:1: note: in expansion of macro 'TRACE_EVENT'
TRACE_EVENT(signal_deliver,
^~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/trace_signal_deliver +24 include/uapi/asm-generic/signal-defs.h
b1ecb4c3 include/asm-generic/signal.h Al Viro 2005-05-04 23
b1ecb4c3 include/asm-generic/signal.h Al Viro 2005-05-04 @24 #define SIG_DFL ((__force __sighandler_t)0) /* default signal handling */
b1ecb4c3 include/asm-generic/signal.h Al Viro 2005-05-04 25 #define SIG_IGN ((__force __sighandler_t)1) /* ignore signal */
b1ecb4c3 include/asm-generic/signal.h Al Viro 2005-05-04 26 #define SIG_ERR ((__force __sighandler_t)-1) /* error return from signal */
b1ecb4c3 include/asm-generic/signal.h Al Viro 2005-05-04 27 #endif
ad158879 include/asm-generic/signal.h David Woodhouse 2006-04-27 28
:::::: The code at line 24 was first introduced by commit
:::::: b1ecb4c3a9e33cc8b93ac9cb046b535b72a15f68 [PATCH] asm/signal.h unification
:::::: TO: Al Viro <viro@http://www.linux.org.uk>
:::::: CC: Linus Torvalds <[email protected]>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Zhenliang,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.1-rc6 next-20190418]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Zhenliang-Wei/signal-trace_signal_deliver-when-signal_group_exit/20190423-062107
config: parisc-allyesconfig (attached as .config)
compiler: hppa-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.2.0 make.cross ARCH=parisc
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <[email protected]>
All errors (new ones prefixed by >>):
In file included from arch/parisc/include/asm/signal.h:5:0,
from include/uapi/linux/signal.h:5,
from include/linux/signal_types.h:10,
from include/linux/sched.h:28,
from include/linux/sched/mm.h:7,
from kernel/signal.c:16:
kernel/signal.c: In function 'get_signal':
>> arch/parisc/include/uapi/asm/signal.h:77:17: error: passing argument 3 of 'trace_signal_deliver' from incompatible pointer type [-Werror=incompatible-pointer-types]
#define SIG_DFL ((__sighandler_t)0) /* default signal handling */
^
kernel/signal.c:2444:50: note: in expansion of macro 'SIG_DFL'
trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
^~~~~~~
In file included from include/trace/syscall.h:5:0,
from include/linux/syscalls.h:86,
from kernel/signal.c:29:
include/linux/tracepoint.h:235:21: note: expected 'struct k_sigaction *' but argument is of type 'void (*)(int)'
static inline void trace_##name(proto) \
^
include/linux/tracepoint.h:398:2: note: in expansion of macro '__DECLARE_TRACE'
__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \
^~~~~~~~~~~~~~~
include/linux/tracepoint.h:534:2: note: in expansion of macro 'DECLARE_TRACE'
DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
^~~~~~~~~~~~~
include/trace/events/signal.h:96:1: note: in expansion of macro 'TRACE_EVENT'
TRACE_EVENT(signal_deliver,
^~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/trace_signal_deliver +77 arch/parisc/include/uapi/asm/signal.h
70c1674f6 David Howells 2012-10-16 76
70c1674f6 David Howells 2012-10-16 @77 #define SIG_DFL ((__sighandler_t)0) /* default signal handling */
70c1674f6 David Howells 2012-10-16 78 #define SIG_IGN ((__sighandler_t)1) /* ignore signal */
70c1674f6 David Howells 2012-10-16 79 #define SIG_ERR ((__sighandler_t)-1) /* error return from signal */
70c1674f6 David Howells 2012-10-16 80
:::::: The code at line 77 was first introduced by commit
:::::: 70c1674f62026e455c0c821fb7f4baf24d2d1139 UAPI: (Scripted) Disintegrate arch/parisc/include/asm
:::::: TO: David Howells <[email protected]>
:::::: CC: David Howells <[email protected]>
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
On Mon, Apr 22, 2019 at 11:25 PM Oleg Nesterov <[email protected]> wrote:
>On 04/22, Zhenliang Wei wrote:
>>
>> --- a/kernel/signal.c
>> +++ b/kernel/signal.c
>> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
>> if (signal_group_exit(signal)) {
>> ksig->info.si_signo = signr = SIGKILL;
>> sigdelset(¤t->pending.signal, SIGKILL);
>> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
>> recalc_sigpending();
>> goto fatal;
>> }
>
>Reviewed-by: Oleg Nesterov <[email protected]>
Last time Oleg suggested using SIG_DFL as the third parameter, but its type is 'void (*)(int)', but not expected 'struct k_sigaction *'.
How about
trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, &sighand->action[signr - 1]);
?
Although we know that action[SIGKILL] must be SIG_DFL, in order to adapt to the parameter type, I suggest to use the original variable value.
Zhenliang Wei.
On Tue, Apr 23, 2019 at 01:10:52PM +0000, weizhenliang wrote:
> On Mon, Apr 22, 2019 at 11:25 PM Oleg Nesterov <[email protected]> wrote:
> >On 04/22, Zhenliang Wei wrote:
> >>
> >> --- a/kernel/signal.c
> >> +++ b/kernel/signal.c
> >> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
> >> if (signal_group_exit(signal)) {
> >> ksig->info.si_signo = signr = SIGKILL;
> >> sigdelset(¤t->pending.signal, SIGKILL);
> >> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
> >> recalc_sigpending();
> >> goto fatal;
> >> }
> >
> >Reviewed-by: Oleg Nesterov <[email protected]>
>
> Last time Oleg suggested using SIG_DFL as the third parameter, but its type is 'void (*)(int)', but not expected 'struct k_sigaction *'.
Sigh, I should've caught that in the first commit.
Although it suggests you didn't even compile your patch...
>
> How about
> trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, &sighand->action[signr - 1]);
> ?
That should work, yes.
Christian
On 04/23, weizhenliang wrote:
>
> On Mon, Apr 22, 2019 at 11:25 PM Oleg Nesterov <[email protected]> wrote:
> >On 04/22, Zhenliang Wei wrote:
> >>
> >> --- a/kernel/signal.c
> >> +++ b/kernel/signal.c
> >> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
> >> if (signal_group_exit(signal)) {
> >> ksig->info.si_signo = signr = SIGKILL;
> >> sigdelset(¤t->pending.signal, SIGKILL);
> >> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
> >> recalc_sigpending();
> >> goto fatal;
> >> }
> >
> >Reviewed-by: Oleg Nesterov <[email protected]>
>
> Last time Oleg suggested using SIG_DFL as the third parameter, but its type is 'void (*)(int)', but not expected 'struct k_sigaction *'.
Yes I misread the signature of TRACE_EVENT(signal_deliver), and I thought you at
least compiled the kernel with your patch applied ;)
> How about
> trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, &sighand->action[signr - 1]);
> ?
sure, this should fix the problem.
Oleg.
On Tue, Apr 23, 2019 at 09:41 PM Christian wrote:
>On Tue, Apr 23, 2019 at 01:10:52PM +0000, weizhenliang wrote:
>> On Mon, Apr 22, 2019 at 11:25 PM Oleg Nesterov <[email protected]> wrote:
>> >On 04/22, Zhenliang Wei wrote:
>> >>
>> >> --- a/kernel/signal.c
>> >> +++ b/kernel/signal.c
>> >> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
>> >> if (signal_group_exit(signal)) {
>> >> ksig->info.si_signo = signr = SIGKILL;
>> >> sigdelset(¤t->pending.signal, SIGKILL);
>> >> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
>> >> recalc_sigpending();
>> >> goto fatal;
>> >> }
>> >
>> >Reviewed-by: Oleg Nesterov <[email protected]>
>>
>> Last time Oleg suggested using SIG_DFL as the third parameter, but its type is 'void (*)(int)', but not expected 'struct k_sigaction *'.
>
>Sigh, I should've caught that in the first commit.
>Although it suggests you didn't even compile your patch...
>
>>
>> How about
>> trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, &sighand->action[signr
>> - 1]); ?
>
>That should work, yes.
Sorry about that, I was too focused on the functionality and didn't notice the compile warning.
And thanks for your reply, I will pay more attention to it in the future.
Zhenliang Wei
On 04/23, Oleg wrote:
>On 04/23, weizhenliang wrote:
>>
>> Last time Oleg suggested using SIG_DFL as the third parameter, but its type is 'void (*)(int)', but not expected 'struct k_sigaction *'.
>
>Yes I misread the signature of TRACE_EVENT(signal_deliver), and I thought you at least compiled the kernel with your patch applied ;)
>
>> How about
>> trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, &sighand->action[signr
>> - 1]); ?
>
>sure, this should fix the problem.
Sorry about that, I will pay more attention to it in the future.
And thanks for your reply, I will re-adjust the patch later.
Wei.
On 04/23, Greg KH wrote:
>On Mon, Apr 22, 2019 at 10:59:50PM +0800, Zhenliang Wei wrote:
>> In the fixes commit, removing SIGKILL from each thread signal mask and
>> executing "goto fatal" directly will skip the call to
>> "trace_signal_deliver". At this point, the delivery tracking of the
>> SIGKILL signal will be inaccurate.
>>
>> Therefore, we need to add trace_signal_deliver before "goto fatal"
>> after executing sigdelset.
>>
>> Note: The action[SIGKILL] must be SIG_DFL, and SEND_SIG_NOINFO matches
>> the fact that SIGKILL doesn't have any info.
>>
>> Acked-by: Christian Brauner <[email protected]>
>> Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT")
>> Signed-off-by: Zhenliang Wei <[email protected]>
>> ---
>> kernel/signal.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/kernel/signal.c b/kernel/signal.c index
>> 227ba170298e..0f69ada376ef 100644
>> --- a/kernel/signal.c
>> +++ b/kernel/signal.c
>> @@ -2441,6 +2441,7 @@ bool get_signal(struct ksignal *ksig)
>> if (signal_group_exit(signal)) {
>> ksig->info.si_signo = signr = SIGKILL;
>> sigdelset(¤t->pending.signal, SIGKILL);
>> + trace_signal_deliver(SIGKILL, SEND_SIG_NOINFO, SIG_DFL);
>> recalc_sigpending();
>> goto fatal;
>> }
>> --
>> 2.14.1.windows.1
>>
>>
>
><formletter>
>
>This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read:
> https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
>for how to do this properly.
>
></formletter>
Thans for your reply, is that mean I still need to add tags
Cc: [email protected]
if I want to submit this patch to the stable kernel tree?
Is my understanding correct or missing?
Wei