From: Rasmus Villemoes Date: Thu, 12 Feb 2015 23:01:39 +0000 (-0800) Subject: lib/vsprintf.c: improve sanity check in vsnprintf() X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=2aa2f9e21e4e;p=openwrt%2Fstaging%2Fblogic.git lib/vsprintf.c: improve sanity check in vsnprintf() On 64 bit, size may very well be huge even if bit 31 happens to be 0. Somehow it doesn't feel right that one can pass a 5 GiB buffer but not a 3 GiB one. So cap at INT_MAX as was probably the intention all along. This is also the made-up value passed by sprintf and vsprintf. Signed-off-by: Rasmus Villemoes Cc: Jiri Kosina Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 98ad170b10e0..cf12ba86205c 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1727,7 +1727,7 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) /* Reject out-of-range values early. Large positive sizes are used for unknown buffer sizes. */ - if (WARN_ON_ONCE((int) size < 0)) + if (WARN_ON_ONCE(size > INT_MAX)) return 0; str = buf;