| Subject | Re: [PATCH 11/20] signal/s390: Use force_sigsegv in default_trap_handler | From | Christian Borntraeger <> | Date | Tue, 26 Oct 2021 11:38:44 +0200 |
| |
Am 20.10.21 um 19:43 schrieb Eric W. Biederman: > Reading the history it is unclear why default_trap_handler calls > do_exit. It is not even menthioned in the commit where the change > happened. My best guess is that because it is unknown why the > exception happened it was desired to guarantee the process never > returned to userspace. > > Using do_exit(SIGSEGV) has the problem that it will only terminate one > thread of a process, leaving the process in an undefined state. > > Use force_sigsegv(SIGSEGV) instead which effectively has the same > behavior except that is uses the ordinary signal mechanism and > terminates all threads of a process and is generally well defined.
Do I get that right, that programs can not block SIGSEGV from force_sigsegv with a signal handler? Thats how I read the code. If this is true then
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> > > Cc: Heiko Carstens <hca@linux.ibm.com> > Cc: Vasily Gorbik <gor@linux.ibm.com> > Cc: Christian Borntraeger <borntraeger@de.ibm.com> > Cc: linux-s390@vger.kernel.org > Fixes: ca2ab03237ec ("[PATCH] s390: core changes") > History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git > Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> > --- > arch/s390/kernel/traps.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c > index bcefc2173de4..51729ea2cf8e 100644 > --- a/arch/s390/kernel/traps.c > +++ b/arch/s390/kernel/traps.c > @@ -84,7 +84,7 @@ static void default_trap_handler(struct pt_regs *regs) > { > if (user_mode(regs)) { > report_user_fault(regs, SIGSEGV, 0); > - do_exit(SIGSEGV); > + force_sigsegv(SIGSEGV); > } else > die(regs, "Unknown program exception"); > } >
|