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 <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 @@
* 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;