From a399a8053164ec8bcb06fed52be9941a26ecde11 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 8 Aug 2012 21:13:53 +0000 Subject: time: jiffies_delta_to_clock_t() helper to the rescue MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Various /proc/net files sometimes report crazy timer values, expressed in clock_t units. This happens when an expired timer delta (expires - jiffies) is passed to jiffies_to_clock_t(). This function has an overflow in : return div_u64((u64)x * TICK_NSEC, NSEC_PER_SEC / USER_HZ); commit cbbc719fccdb8cb (time: Change jiffies_to_clock_t() argument type to unsigned long) only got around the problem. As we cant output negative values in /proc/net/tcp without breaking various tools, I suggest adding a jiffies_delta_to_clock_t() wrapper that caps the negative delta to a 0 value. Signed-off-by: Eric Dumazet Reported-by: Maciej Żenczykowski Cc: Thomas Gleixner Cc: Paul Gortmaker Cc: Andrew Morton Cc: hank Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/rtnetlink.c') diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 2c5a0a06c4c..db037c9a4c4 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -618,7 +618,7 @@ int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id, long expires, u32 error) { struct rta_cacheinfo ci = { - .rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse), + .rta_lastuse = jiffies_delta_to_clock_t(jiffies - dst->lastuse), .rta_used = dst->__use, .rta_clntref = atomic_read(&(dst->__refcnt)), .rta_error = error, -- cgit v1.2.3-70-g09d2