[PATCH] mailmap: avoid out-of-bounds memory access

From: Romain Francoise <romain@orebokech.com>
Date: Oct 27, 2012, 22:49 UTC
Message-ID: <87k3ub4jjg.fsf@silenus.orebokech.com>

AddressSanitizer (http://clang.llvm.org/docs/AddressSanitizer.html) complains of a one-byte buffer underflow in parse_name_and_email() while running the test suite. And indeed, if one of the lines in the mailmap begins with '<', we dereference the address just before the beginning of the buffer when looking for whitespace to remove, before checking that we aren't going too far.

So reverse the order of the tests to make sure that we don't read outside the buffer.

Signed-off-by: Romain Francoise <romain@orebokech.com>
---
 mailmap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mailmap.c b/mailmap.c
index 47aa419..ea4b471 100644
--- a/mailmap.c
+++ b/mailmap.c
@@ -118,7 +118,7 @@ static char *parse_name_and_email(char *buffer, char **name,
 	while (isspace(*nstart) && nstart < left)
 		++nstart;
 	nend = left-1;
-	while (isspace(*nend) && nend > nstart)
+	while (nend > nstart && isspace(*nend))
 		--nend;
 
 	*name = (nstart < nend ? nstart : NULL);

-- 
1.7.10.4