From: Eliad Peller <eliad@wizery.com>
Date: Tue, 17 Jun 2014 10:07:02 +0000 (+0300)
Subject: cfg80211: fix elapsed_jiffies calculation
X-Git-Tag: firefly_0821_release~176^2~3540^2~11^2~1^2~4
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0ce12026d6ea4a24d52ddcde36b9643f2e26d560;p=firefly-linux-kernel-4.4.55.git

cfg80211: fix elapsed_jiffies calculation

MAX_JIFFY_OFFSET has no meaning when calculating the
elapsed jiffies, as jiffies run out until ULONG_MAX.

This miscalculation results in erroneous values
in case of a wrap-around.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---

diff --git a/net/wireless/core.h b/net/wireless/core.h
index e9afbf10e756..7e3a3cef7df9 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -424,7 +424,7 @@ static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
 	if (end >= start)
 		return jiffies_to_msecs(end - start);
 
-	return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
+	return jiffies_to_msecs(end + (ULONG_MAX - start) + 1);
 }
 
 void