batman-adv: make batadv_test_bit() return 0 or 1 only

[ Upstream commit dbd6b11e15a2f96030da17dbeda943a8a98ee990 ]

On some architectures test_bit() can return other values than 0 or 1:

With a generic x86 OpenWrt image in a kvm setup (batadv_)test_bit()
frequently returns -1 for me, leading to batadv_iv_ogm_update_seqnos()
wrongly signaling a protected seqno window.

This patch tries to fix this issue by making batadv_test_bit() return 0
or 1 only.

Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/batman-adv/bitarray.h b/net/batman-adv/bitarray.h
index 1835c15cda411d5338e03dbff1c32fb9dd35ab20..7d1840bd5a2f7bafb985c3084da0b5075ae04144 100644 (file)
--- a/net/batman-adv/bitarray.h
+++ b/net/batman-adv/bitarray.h
@@ -22,8 +22,9 @@
 #ifndef _NET_BATMAN_ADV_BITARRAY_H_
 #define _NET_BATMAN_ADV_BITARRAY_H_
 
-/* returns true if the corresponding bit in the given seq_bits indicates true
- * and curr_seqno is within range of last_seqno */
+/* Returns 1 if the corresponding bit in the given seq_bits indicates true
+ * and curr_seqno is within range of last_seqno. Otherwise returns 0.
+ */
 static inline int bat_test_bit(const unsigned long *seq_bits,
                               uint32_t last_seqno, uint32_t curr_seqno)
 {
@@ -33,7 +34,7 @@ static inline int bat_test_bit(const unsigned long *seq_bits,
        if (diff < 0 || diff >= TQ_LOCAL_WINDOW_SIZE)
                return 0;
        else
-               return  test_bit(diff, seq_bits);
+               return test_bit(diff, seq_bits) != 0;
 }
 
 /* turn corresponding bit on, so we can remember that we got the packet */