[PATCH] convert signal handling of NODEFER to act like other Unix boxes.

It has been reported that the way Linux handles NODEFER for signals is not consistent with the way other Unix boxes handle it. I've written a program to test the behavior of how this flag affects signals and had several reports from people who ran this on various Unix boxes, confirming that Linux seems to be unique on the way this is handled. The way NODEFER affects signals on other Unix boxes is as follows: 1) If NODEFER is set, other signals in sa_mask are still blocked. 2) If NODEFER is set and the signal is in sa_mask, then the signal is still blocked. (Note: this is the behavior of all tested but Linux _and_ NetBSD 2.0 *). The way NODEFER affects signals on Linux: 1) If NODEFER is set, other signals are _not_ blocked regardless of sa_mask (Even NetBSD doesn't do this). 2) If NODEFER is set and the signal is in sa_mask, then the signal being handled is not blocked. The patch converts signal handling in all current Linux architectures to the way most Unix boxes work. Unix boxes that were tested: DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU 3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX. * NetBSD was the only other Unix to behave like Linux on point #2. The main concern was brought up by point #1 which even NetBSD isn't like Linux. So with this patch, we leave NetBSD as the lonely one that behaves differently here with #2. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
joolstorrentecalo · Aug 29, 2005 · 69be8f1 · 69be8f1
1 parent 02b3e4e
commit 69be8f1
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Showing 29 changed files with 135 additions and 155 deletions.
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
@@ -566,13 +566,12 @@ handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
 	if (ka->sa.sa_flags & SA_RESETHAND)
 		ka->sa.sa_handler = SIG_DFL;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER)) 
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 static inline void

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
@@ -658,11 +658,12 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
 	/*
 	 * Block the signal if we were unsuccessful.
 	 */
-	if (ret != 0 || !(ka->sa.sa_flags & SA_NODEFER)) {
+	if (ret != 0) {
 		spin_lock_irq(&tsk->sighand->siglock);
 		sigorsets(&tsk->blocked, &tsk->blocked,
 			  &ka->sa.sa_mask);
-		sigaddset(&tsk->blocked, sig);
+		if (!(ka->sa.sa_flags & SA_NODEFER))
+			sigaddset(&tsk->blocked, sig);
 		recalc_sigpending();
 		spin_unlock_irq(&tsk->sighand->siglock);
 	}

diff --git a/arch/arm26/kernel/signal.c b/arch/arm26/kernel/signal.c
@@ -454,14 +454,13 @@ handle_signal(unsigned long sig, siginfo_t *info, sigset_t *oldset,
 		if (ka->sa.sa_flags & SA_ONESHOT)
 			ka->sa.sa_handler = SIG_DFL;
 
-		if (!(ka->sa.sa_flags & SA_NODEFER)) {
-			spin_lock_irq(&tsk->sighand->siglock);
-			sigorsets(&tsk->blocked, &tsk->blocked,
-				  &ka->sa.sa_mask);
+		spin_lock_irq(&tsk->sighand->siglock);
+		sigorsets(&tsk->blocked, &tsk->blocked,
+			  &ka->sa.sa_mask);
+		if (!(ka->sa.sa_flags & SA_NODEFER))
 			sigaddset(&tsk->blocked, sig);
-			recalc_sigpending();
-			spin_unlock_irq(&tsk->sighand->siglock);
-		}
+		recalc_sigpending();
+		spin_unlock_irq(&tsk->sighand->siglock);
 		return;
 	}
 

diff --git a/arch/cris/arch-v10/kernel/signal.c b/arch/cris/arch-v10/kernel/signal.c
@@ -517,13 +517,12 @@ handle_signal(int canrestart, unsigned long sig,
 	if (ka->sa.sa_flags & SA_ONESHOT)
 		ka->sa.sa_handler = SIG_DFL;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/cris/arch-v32/kernel/signal.c b/arch/cris/arch-v32/kernel/signal.c
@@ -568,13 +568,12 @@ handle_signal(int canrestart, unsigned long sig,
 	if (ka->sa.sa_flags & SA_ONESHOT)
 		ka->sa.sa_handler = SIG_DFL;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/frv/kernel/signal.c b/arch/frv/kernel/signal.c
@@ -506,13 +506,12 @@ static void handle_signal(unsigned long sig, siginfo_t *info,
 	else
 		setup_frame(sig, ka, oldset, regs);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked, sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 } /* end handle_signal() */
 
 /*****************************************************************************/

diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c
@@ -488,13 +488,12 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	else
 		setup_frame(sig, ka, oldset, regs);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/i386/kernel/signal.c b/arch/i386/kernel/signal.c
@@ -577,10 +577,11 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	else
 		ret = setup_frame(sig, ka, oldset, regs);
 
-	if (ret && !(ka->sa.sa_flags & SA_NODEFER)) {
+	if (ret) {
 		spin_lock_irq(&current->sighand->siglock);
 		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
-		sigaddset(&current->blocked,sig);
+		if (!(ka->sa.sa_flags & SA_NODEFER))
+			sigaddset(&current->blocked,sig);
 		recalc_sigpending();
 		spin_unlock_irq(&current->sighand->siglock);
 	}

diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
@@ -467,15 +467,12 @@ handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigse
 		if (!setup_frame(sig, ka, info, oldset, scr))
 			return 0;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		{
-			sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
-			sigaddset(&current->blocked, sig);
-			recalc_sigpending();
-		}
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
+		sigaddset(&current->blocked, sig);
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 	return 1;
 }
 

diff --git a/arch/m32r/kernel/signal.c b/arch/m32r/kernel/signal.c
@@ -341,13 +341,12 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
 	/* Set up the stack frame */
 	setup_rt_frame(sig, ka, info, oldset, regs);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/m68knommu/kernel/signal.c b/arch/m68knommu/kernel/signal.c
@@ -732,13 +732,12 @@ handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
 	if (ka->sa.sa_flags & SA_ONESHOT)
 		ka->sa.sa_handler = SIG_DFL;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/mips/kernel/irixsig.c b/arch/mips/kernel/irixsig.c
@@ -155,13 +155,12 @@ static inline void handle_signal(unsigned long sig, siginfo_t *info,
 	else
 		setup_irix_frame(ka, regs, sig, oldset);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 asmlinkage int do_irix_signal(sigset_t *oldset, struct pt_regs *regs)

diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
@@ -425,13 +425,12 @@ static inline void handle_signal(unsigned long sig, siginfo_t *info,
 		setup_frame(ka, regs, sig, oldset);
 #endif
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 extern int do_signal32(sigset_t *oldset, struct pt_regs *regs);

diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
@@ -751,13 +751,12 @@ static inline void handle_signal(unsigned long sig, siginfo_t *info,
 	else
 		setup_frame(ka, regs, sig, oldset);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 int do_signal32(sigset_t *oldset, struct pt_regs *regs)

diff --git a/arch/parisc/kernel/signal.c b/arch/parisc/kernel/signal.c
@@ -517,13 +517,12 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall))
 		return 0;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 	return 1;
 }
 

diff --git a/arch/ppc/kernel/signal.c b/arch/ppc/kernel/signal.c
@@ -759,13 +759,12 @@ int do_signal(sigset_t *oldset, struct pt_regs *regs)
 	else
 		handle_signal(signr, &ka, &info, oldset, regs, newsp);
 
-	if (!(ka.sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka.sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka.sa.sa_mask);
+	if (!(ka.sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked, signr);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 
 	return 1;
 }

diff --git a/arch/ppc64/kernel/signal.c b/arch/ppc64/kernel/signal.c
@@ -481,10 +481,11 @@ static int handle_signal(unsigned long sig, struct k_sigaction *ka,
 	/* Set up Signal Frame */
 	ret = setup_rt_frame(sig, ka, info, oldset, regs);
 
-	if (ret && !(ka->sa.sa_flags & SA_NODEFER)) {
+	if (ret) {
 		spin_lock_irq(&current->sighand->siglock);
 		sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
-		sigaddset(&current->blocked,sig);
+		if (!(ka->sa.sa_flags & SA_NODEFER))
+			sigaddset(&current->blocked,sig);
 		recalc_sigpending();
 		spin_unlock_irq(&current->sighand->siglock);
 	}

diff --git a/arch/ppc64/kernel/signal32.c b/arch/ppc64/kernel/signal32.c
@@ -976,11 +976,12 @@ int do_signal32(sigset_t *oldset, struct pt_regs *regs)
 	else
 		ret = handle_signal32(signr, &ka, &info, oldset, regs, newsp);
 
-	if (ret && !(ka.sa.sa_flags & SA_NODEFER)) {
+	if (ret) {
 		spin_lock_irq(&current->sighand->siglock);
 		sigorsets(&current->blocked, &current->blocked,
 			  &ka.sa.sa_mask);
-		sigaddset(&current->blocked, signr);
+		if (!(ka.sa.sa_flags & SA_NODEFER))
+			sigaddset(&current->blocked, signr);
 		recalc_sigpending();
 		spin_unlock_irq(&current->sighand->siglock);
 	}

diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
@@ -637,12 +637,11 @@ handle_signal32(unsigned long sig, struct k_sigaction *ka,
 	else
 		setup_frame32(sig, ka, oldset, regs);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
@@ -429,13 +429,12 @@ handle_signal(unsigned long sig, struct k_sigaction *ka,
 	else
 		setup_frame(sig, ka, oldset, regs);
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*

diff --git a/arch/sh/kernel/signal.c b/arch/sh/kernel/signal.c
@@ -546,13 +546,12 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
 	if (ka->sa.sa_flags & SA_ONESHOT)
 		ka->sa.sa_handler = SIG_DFL;
 
-	if (!(ka->sa.sa_flags & SA_NODEFER)) {
-		spin_lock_irq(&current->sighand->siglock);
-		sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	spin_lock_irq(&current->sighand->siglock);
+	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
+	if (!(ka->sa.sa_flags & SA_NODEFER))
 		sigaddset(&current->blocked,sig);
-		recalc_sigpending();
-		spin_unlock_irq(&current->sighand->siglock);
-	}
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
 }
 
 /*