[PATCH] arm64: signal: don't force known signals to SIGKILL

[Mark Rutland]

Since commit:

  a7e6f1ca90354a31 ("arm64: signal: Force SIGKILL for unknown signals in force_signal_inject")

... any signal which is not SIGKILL will be upgraded to a SIGKILL be
force_signal_inject(). This includes signals we do expect, such as
SIGILL triggered by do_undefinstr().

Fix the check to use a logical AND rather than a logical OR, permitting
signals whose layout is SIL_FAULT.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Fixes: a7e6f1ca90354a31 ("arm64: signal: Force SIGKILL for unknown signals in force_signal_inject")
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Dave Martin <dave.martin at arm.com>
Cc: Will Deacon <will.deacon at arm.com>
---
 arch/arm64/kernel/traps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index ba964da31a25..1cb2749a72bf 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -366,7 +366,7 @@ void force_signal_inject(int signal, int code, unsigned long address)
 	}
 
 	/* Force signals we don't understand to SIGKILL */
-	if (WARN_ON(signal != SIGKILL ||
+	if (WARN_ON(signal != SIGKILL &&
 		    siginfo_layout(signal, code) != SIL_FAULT)) {
 		signal = SIGKILL;
 	}
-- 
2.11.0