From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jim Meyering Subject: [PATCH 4/4] mkfs: avoid heap-buffer-read-underrun for zero-length "size" arg Date: Fri, 20 Apr 2012 19:36:48 +0200 Message-ID: <1334943408-6720-5-git-send-email-jim@meyering.net> References: <1334943408-6720-1-git-send-email-jim@meyering.net> To: linux-btrfs@vger.kernel.org Return-path: In-Reply-To: <1334943408-6720-1-git-send-email-jim@meyering.net> List-ID: From: Jim Meyering * mkfs.c (parse_size): ./mkfs.btrfs -A '' would read and possibly write the byte before beginning of strdup'd heap buffer. All other size-accepting options were similarly affected. --- mkfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mkfs.c b/mkfs.c index 03239fb..4aff2fd 100644 --- a/mkfs.c +++ b/mkfs.c @@ -63,7 +63,7 @@ static u64 parse_size(char *s) s = strdup(s); - if (!isdigit(s[len - 1])) { + if (len && !isdigit(s[len - 1])) { c = tolower(s[len - 1]); switch (c) { case 'g': -- 1.7.10.208.gb4267