diff options
Diffstat (limited to 'php-bug81726.patch')
-rw-r--r-- | php-bug81726.patch | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/php-bug81726.patch b/php-bug81726.patch new file mode 100644 index 0000000..53dcde3 --- /dev/null +++ b/php-bug81726.patch @@ -0,0 +1,88 @@ +From 2bdc26af43cdd4376bf8e0fdf532bb12dd35d3dd Mon Sep 17 00:00:00 2001 +From: "Christoph M. Becker" <cmbecker69@gmx.de> +Date: Mon, 25 Jul 2022 15:58:59 +0200 +Subject: [PATCH 2/2] Fix #81726: phar wrapper: DOS when using quine gzip file + +The phar wrapper needs to uncompress the file; the uncompressed file +might be compressed, so the wrapper implementation loops. This raises +potential DOS issues regarding too deep or even infinite recursion (the +latter are called compressed file quines[1]). We avoid that by +introducing a recursion limit; we choose the somewhat arbitrary limit +`3`. + +This issue has been reported by real_as3617 and gPayl0ad. + +[1] <https://honno.dev/gzip-quine/> + +(cherry picked from commit 404e8bdb68350931176a5bdc86fc417b34fb583d) +(cherry picked from commit 96fda78bcddd1d793cf2d0ee463dbb49621b577f) +--- + NEWS | 2 ++ + ext/phar/phar.c | 16 +++++++++++----- + ext/phar/tests/bug81726.gz | Bin 0 -> 204 bytes + ext/phar/tests/bug81726.phpt | 14 ++++++++++++++ + 4 files changed, 27 insertions(+), 5 deletions(-) + create mode 100644 ext/phar/tests/bug81726.gz + create mode 100644 ext/phar/tests/bug81726.phpt + +diff --git a/NEWS b/NEWS +index 90ac6b751b..be8bfd2f98 100644 +--- a/NEWS ++++ b/NEWS +@@ -4,6 +4,8 @@ PHP NEWS + Backported from 7.4.31 + + - Core: ++ . Fixed bug #81726: phar wrapper: DOS when using quine gzip file. ++ (CVE-2022-31628). (cmb) + . Fixed bug #81727: Don't mangle HTTP variable names that clash with ones + that have a specific semantic meaning. (CVE-2022-31629). (Derick) + +diff --git a/ext/phar/phar.c b/ext/phar/phar.c +index ba76a9b0e0..52c973d7c4 100644 +--- a/ext/phar/phar.c ++++ b/ext/phar/phar.c +@@ -1575,7 +1575,8 @@ static int phar_open_from_fp(php_stream* fp, char *fname, int fname_len, char *a + const char zip_magic[] = "PK\x03\x04"; + const char gz_magic[] = "\x1f\x8b\x08"; + const char bz_magic[] = "BZh"; +- char *pos, test = '\0'; ++ char *pos; ++ int recursion_count = 3; // arbitrary limit to avoid too deep or even infinite recursion + const int window_size = 1024; + char buffer[1024 + sizeof(token)]; /* a 1024 byte window + the size of the halt_compiler token (moving window) */ + const zend_long readsize = sizeof(buffer) - sizeof(token); +@@ -1603,8 +1604,7 @@ static int phar_open_from_fp(php_stream* fp, char *fname, int fname_len, char *a + MAPPHAR_ALLOC_FAIL("internal corruption of phar \"%s\" (truncated entry)") + } + +- if (!test) { +- test = '\1'; ++ if (recursion_count) { + pos = buffer+tokenlen; + if (!memcmp(pos, gz_magic, 3)) { + char err = 0; +@@ -1664,7 +1664,10 @@ static int phar_open_from_fp(php_stream* fp, char *fname, int fname_len, char *a + compression = PHAR_FILE_COMPRESSED_GZ; + + /* now, start over */ +- test = '\0'; ++ if (!--recursion_count) { ++ MAPPHAR_ALLOC_FAIL("unable to decompress gzipped phar archive \"%s\""); ++ break; ++ } + continue; + } else if (!memcmp(pos, bz_magic, 3)) { + php_stream_filter *filter; +@@ -1702,7 +1705,10 @@ static int phar_open_from_fp(php_stream* fp, char *fname, int fname_len, char *a + compression = PHAR_FILE_COMPRESSED_BZ2; + + /* now, start over */ +- test = '\0'; ++ if (!--recursion_count) { ++ MAPPHAR_ALLOC_FAIL("unable to decompress bzipped phar archive \"%s\""); ++ break; ++ } + continue; + } + |