[PATCH 1/2] mn10300/misalignment: Use SIGSEGV SEGV_MAPERR to report a failed user copy

From: Eric W. Biederman
Date: Fri Jan 12 2018 - 15:32:58 EST


Setting si_code to 0 is the same a setting si_code to SI_USER which is definitely
not correct. With si_code set to SI_USER si_pid and si_uid will be copied to
userspace instead of si_addr. Which is very wrong.

So fix this by using a sensible si_code (SEGV_MAPERR) for this failure.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: b920de1b77b7 ("mn10300: add the MN10300/AM33 architecture to the kernel")
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Masakazu Urade <urade.masakazu@xxxxxxxxxxxxxxxx>
Cc: Koichi Yasutake <yasutake.koichi@xxxxxxxxxxxxxxxx>
Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
---
arch/mn10300/mm/misalignment.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mn10300/mm/misalignment.c b/arch/mn10300/mm/misalignment.c
index b39a388825ae..8ace89617c1c 100644
--- a/arch/mn10300/mm/misalignment.c
+++ b/arch/mn10300/mm/misalignment.c
@@ -437,7 +437,7 @@ asmlinkage void misalignment(struct pt_regs *regs, enum exception_code code)

info.si_signo = SIGSEGV;
info.si_errno = 0;
- info.si_code = 0;
+ info.si_code = SEGV_MAPERR;
info.si_addr = (void *) regs->pc;
force_sig_info(SIGSEGV, &info, current);
return;
--
2.14.1