[PATCH] arm64: signal32: Drop pointless call to sigdelsetmask()

[PATCH] arm64: signal32: Drop pointless call to sigdelsetmask()

[Will Deacon]

Commit 77097ae503b1 ("most of set_current_blocked() callers want
SIGKILL/SIGSTOP removed from set") extended set_current_blocked() to
remove SIGKILL and SIGSTOP from the new signal set and updated all
callers accordingly.

Unfortunately, this collided with the merge of the arm64 architecture,
which duly removes these signals when restoring the compat sigframe, as
this was what was previously done by arch/arm/.

Remove the redundant call to sigdelsetmask() from
compat_restore_sigframe().

Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kernel/signal32.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index 2f507f565c48..4850333669fb 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -46,8 +46,6 @@ struct compat_aux_sigframe {
 	unsigned long			end_magic;
 } __attribute__((__aligned__(8)));
 
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
 static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
 {
 	compat_sigset_t	cset;
@@ -190,10 +188,8 @@ static int compat_restore_sigframe(struct pt_regs *regs,
 	unsigned long psr;
 
 	err = get_sigset_t(&set, &sf->uc.uc_sigmask);
-	if (err == 0) {
-		sigdelsetmask(&set, ~_BLOCKABLE);
+	if (err == 0)
 		set_current_blocked(&set);
-	}
 
 	__get_user_error(regs->regs[0], &sf->uc.uc_mcontext.arm_r0, err);
 	__get_user_error(regs->regs[1], &sf->uc.uc_mcontext.arm_r1, err);
-- 
2.33.0.rc2.250.ged5fa647cd-goog

Re: [PATCH] arm64: signal32: Drop pointless call to sigdelsetmask()

[Catalin Marinas]

On Wed, 25 Aug 2021 10:39:11 +0100, Will Deacon wrote:
> Commit 77097ae503b1 ("most of set_current_blocked() callers want
> SIGKILL/SIGSTOP removed from set") extended set_current_blocked() to
> remove SIGKILL and SIGSTOP from the new signal set and updated all
> callers accordingly.
> 
> Unfortunately, this collided with the merge of the arm64 architecture,
> which duly removes these signals when restoring the compat sigframe, as
> this was what was previously done by arch/arm/.
> 
> [...]

Applied to arm64 (for-next/misc), thanks!

[1/1] arm64: signal32: Drop pointless call to sigdelsetmask()
      https://git.kernel.org/arm64/c/24de5838db70

-- 
Catalin