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| author | Stas Sergeev <stsp@list.ru> | 2017-02-27 14:27:25 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-27 18:43:45 -0800 |
| commit | 441398d378f29a5ad6d0fcda07918e54e4961800 (patch) | |
| tree | 29d479819be6aeb995416102d01fea238b978e74 | |
| parent | b899ba7d8c71e2e1c2be281222877c7a1c2ba60d (diff) | |
| download | linux-441398d378f29a5ad6d0fcda07918e54e4961800.tar.gz linux-441398d378f29a5ad6d0fcda07918e54e4961800.tar.xz | |
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>
| -rw-r--r-- | include/linux/compat.h | 4 | ||||
| -rw-r--r-- | kernel/signal.c | 11 |
2 files changed, 12 insertions, 3 deletions
diff --git a/include/linux/compat.h b/include/linux/compat.h index 9e40be522793..aef47be2a5c1 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -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, diff --git a/kernel/signal.c b/kernel/signal.c index 13f9def8b24a..214a8feeb771 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -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 |