kernel/sys.c: compat sysinfo syscall: fix undefined behavior

Fix undefined behavior and compiler warning by replacing right shift 32
with upper_32_bits macro

Signed-off-by: Scotty Bauer <sbauer@eng.utah.edu>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/sys.c b/kernel/sys.c
index 037fd76bdc760ba2fb47801d0ee3af65fcfa1e88..dfce4debd138f1cedc3672c14ae0ad5bc361c6a8 100644 (file)
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2330,7 +2330,7 @@ COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info)
        /* Check to see if any memory value is too large for 32-bit and scale
         *  down if needed
         */
-       if ((s.totalram >> 32) || (s.totalswap >> 32)) {
+       if (upper_32_bits(s.totalram) || upper_32_bits(s.totalswap)) {
                int bitcount = 0;
 
                while (s.mem_unit < PAGE_SIZE) {