From 1da914e0648ace34e1c3738d9584e8b2cd6fe64a Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Wed, 12 Jan 2011 17:01:25 -0800 Subject: decompressors: check input size in decompress_inflate.c Check for end of the input buffer when skipping over the filename field in the .gz file header. Signed-off-by: Lasse Collin Cc: "H. Peter Anvin" Cc: Alain Knaff Cc: Albin Tonnerre Cc: Phillip Lougher Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/decompress_inflate.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'lib') diff --git a/lib/decompress_inflate.c b/lib/decompress_inflate.c index b5fe1d1..19ff89e 100644 --- a/lib/decompress_inflate.c +++ b/lib/decompress_inflate.c @@ -98,13 +98,22 @@ STATIC int INIT gunzip(unsigned char *buf, int len, * possible asciz filename) */ strm->next_in = zbuf + 10; + strm->avail_in = len - 10; /* skip over asciz filename */ if (zbuf[3] & 0x8) { - while (strm->next_in[0]) - strm->next_in++; - strm->next_in++; + do { + /* + * If the filename doesn't fit into the buffer, + * the file is very probably corrupt. Don't try + * to read more data. + */ + if (strm->avail_in == 0) { + error("header error"); + goto gunzip_5; + } + --strm->avail_in; + } while (*strm->next_in++); } - strm->avail_in = len - (strm->next_in - zbuf); strm->next_out = out_buf; strm->avail_out = out_len; -- cgit v1.1