ARM: 7008/1: alignment: Make SIGBUS sent to userspace POSIXly correct
With the UM_SIGNAL alignment fault mode, no siginfo structure is
passed to userspace.
POSIX specifies how siginfo_t should be populated for alignment
faults, so this patch does just that:
* si_signo = SIGBUS
* si_code = BUS_ADRALN
* si_addr = misaligned data address at which access was attempted
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 1df38e8..cfbcf8b 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -22,6 +22,7 @@
#include <linux/sched.h>
#include <linux/uaccess.h>
+#include <asm/system.h>
#include <asm/unaligned.h>
#include "fault.h"
@@ -913,9 +914,16 @@
if (ai_usermode & UM_FIXUP)
goto fixup;
- if (ai_usermode & UM_SIGNAL)
- force_sig(SIGBUS, current);
- else {
+ if (ai_usermode & UM_SIGNAL) {
+ siginfo_t si;
+
+ si.si_signo = SIGBUS;
+ si.si_errno = 0;
+ si.si_code = BUS_ADRALN;
+ si.si_addr = (void __user *)addr;
+
+ force_sig_info(si.si_signo, &si, current);
+ } else {
/*
* We're about to disable the alignment trap and return to
* user space. But if an interrupt occurs before actually