sigaltstack: support SS_AUTODISARM for CONFIG_COMPAT

Currently SS_AUTODISARM is not supported in compatibility mode, but does
not return -EINVAL either.  This makes dosemu built with -m32 on x86_64
to crash.  Also the kernel's sigaltstack selftest fails if compiled with
-m32.

This patch adds the needed support.

Link: http://lkml.kernel.org/r/20170205101213.8163-2-stsp@list.ru
Signed-off-by: Stas Sergeev <stsp@users.sourceforge.net>
Cc: Milosz Tanski <milosz@adfin.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Waiman Long <Waiman.Long@hpe.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Wang Xiaoqiang <wangxq10@lzu.edu.cn>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Stas Sergeev 2017-02-27 14:27:25 -08:00 committed by Linus Torvalds
parent b899ba7d8c
commit 441398d378
2 changed files with 12 additions and 3 deletions

View File

@ -711,8 +711,10 @@ int __compat_save_altstack(compat_stack_t __user *, unsigned long);
compat_stack_t __user *__uss = uss; \
struct task_struct *t = current; \
put_user_ex(ptr_to_compat((void __user *)t->sas_ss_sp), &__uss->ss_sp); \
put_user_ex(sas_ss_flags(sp), &__uss->ss_flags); \
put_user_ex(t->sas_ss_flags, &__uss->ss_flags); \
put_user_ex(t->sas_ss_size, &__uss->ss_size); \
if (t->sas_ss_flags & SS_AUTODISARM) \
sas_ss_reset(t); \
} while (0);
asmlinkage long compat_sys_sched_rr_get_interval(compat_pid_t pid,

View File

@ -3239,10 +3239,17 @@ int compat_restore_altstack(const compat_stack_t __user *uss)
int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
{
int err;
struct task_struct *t = current;
return __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) |
__put_user(sas_ss_flags(sp), &uss->ss_flags) |
err = __put_user(ptr_to_compat((void __user *)t->sas_ss_sp),
&uss->ss_sp) |
__put_user(t->sas_ss_flags, &uss->ss_flags) |
__put_user(t->sas_ss_size, &uss->ss_size);
if (err)
return err;
if (t->sas_ss_flags & SS_AUTODISARM)
sas_ss_reset(t);
return 0;
}
#endif