From 6e06b1c89dd0d16f74894eac4cfc1327a06ee4a0 Mon Sep 17 00:00:00 2001 From: Tim Kientzle Date: Sat, 10 Jan 2015 12:24:58 -0800 Subject: [PATCH] Fix a potential crash issue discovered by Alexander Cherepanov: It seems bsdtar automatically handles stacked compression. This is a nice feature but it could be problematic when it's completely unlimited. Most clearly it's illustrated with quines: $ curl -sRO http://www.maximumcompression.com/selfgz.gz $ (ulimit -v 10000000 && bsdtar -tvf selfgz.gz) bsdtar: Error opening archive: Can't allocate data for gzip decompression Without ulimit, bsdtar will eat all available memory. This could also be a problem for other applications using libarchive. --- Makefile.am | 2 ++ libarchive/archive_read.c | 7 ++-- libarchive/test/CMakeLists.txt | 1 + libarchive/test/test_read_too_many_filters.c | 45 ++++++++++++++++++++++++ libarchive/test/test_read_too_many_filters.gz.uu | 15 ++++++++ 5 files changed, 68 insertions(+), 2 deletions(-) create mode 100644 libarchive/test/test_read_too_many_filters.c create mode 100644 libarchive/test/test_read_too_many_filters.gz.uu diff --git a/libarchive/archive_read.c b/libarchive/archive_read.c index 02bf8d3..8f71a8b 100644 --- a/libarchive/archive_read.c +++ b/libarchive/archive_read.c @@ -548,13 +548,13 @@ archive_read_open1(struct archive *_a) static int choose_filters(struct archive_read *a) { - int number_bidders, i, bid, best_bid; + int number_bidders, i, bid, best_bid, n; struct archive_read_filter_bidder *bidder, *best_bidder; struct archive_read_filter *filter; ssize_t avail; int r; - for (;;) { + for (n = 0; n < 25; ++n) { number_bidders = sizeof(a->bidders) / sizeof(a->bidders[0]); best_bid = 0; @@ -600,6 +600,9 @@ choose_filters(struct archive_read *a) return (ARCHIVE_FATAL); } } + archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT, + "Input requires too many filters for decoding"); + return (ARCHIVE_FATAL); } /*