[PATCH] MIPS: Fix strnlen_user access check

[Thomas Bogendoerfer]

Commit 04324f44cb69 ("MIPS: Remove get_fs/set_fs") changed the access_ok
for strnlen_user to check the whole range, which broke some callers
of strndup_user(). Restore the old behaviour and just check the first byte.

Fixes: 04324f44cb69 ("MIPS: Remove get_fs/set_fs")
Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
---
 arch/mips/include/asm/uaccess.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index ab47e597656a..783fecce65c8 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -614,8 +614,8 @@ static inline long strnlen_user(const char __user *s, long n)
 {
 	long res;
 
-	if (!access_ok(s, n))
-		return -0;
+	if (!access_ok(s, 1))
+		return 0;
 
 	might_fault();
 	__asm__ __volatile__(
-- 
2.29.2