From 7df6795d4c25447683fd4b4a4813bebcddaea547 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Petr=20=C5=A0tetiar?= Date: Sat, 6 Aug 2022 14:55:07 +0200 Subject: [PATCH] zlib: backport fix for heap-based buffer over-read (CVE-2022-37434) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field. NOTE: only applications that call inflateGetHeader are affected. Some common applications bundle the affected zlib source code but may be unable to call inflateGetHeader. Fixes: CVE-2022-37434 References: https://github.com/ivd38/zlib_overflow Signed-off-by: Petr Å tetiar --- .../zlib/patches/006-fix-CVE-2022-37434.patch | 32 +++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 package/libs/zlib/patches/006-fix-CVE-2022-37434.patch diff --git a/package/libs/zlib/patches/006-fix-CVE-2022-37434.patch b/package/libs/zlib/patches/006-fix-CVE-2022-37434.patch new file mode 100644 index 00000000000..dc84d3a1d38 --- /dev/null +++ b/package/libs/zlib/patches/006-fix-CVE-2022-37434.patch @@ -0,0 +1,32 @@ +From eff308af425b67093bab25f80f1ae950166bece1 Mon Sep 17 00:00:00 2001 +From: Mark Adler +Date: Sat, 30 Jul 2022 15:51:11 -0700 +Subject: [PATCH] Fix a bug when getting a gzip header extra field with + inflate(). + +If the extra field was larger than the space the user provided with +inflateGetHeader(), and if multiple calls of inflate() delivered +the extra header data, then there could be a buffer overflow of the +provided space. This commit assures that provided space is not +exceeded. +--- + inflate.c | 5 +++-- + 1 file changed, 3 insertions(+), 2 deletions(-) + +diff --git a/inflate.c b/inflate.c +index 7be8c6366..7a7289749 100644 +--- a/inflate.c ++++ b/inflate.c +@@ -763,9 +763,10 @@ int flush; + copy = state->length; + if (copy > have) copy = have; + if (copy) { ++ len = state->head->extra_len - state->length; + if (state->head != Z_NULL && +- state->head->extra != Z_NULL) { +- len = state->head->extra_len - state->length; ++ state->head->extra != Z_NULL && ++ len < state->head->extra_max) { + zmemcpy(state->head->extra + len, next, + len + copy > state->head->extra_max ? + state->head->extra_max - len : copy); -- 2.30.2