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.
Bug: http://b/242544249
Test: TreeHugger
Change-Id: I648db086d1e93b9f8b803dd106990afb8cbd2a85
(cherry picked from commit b8b2479b4456ff06b3d5496818b836af1dc88818)
Merged-In: I648db086d1e93b9f8b803dd106990afb8cbd2a85
(cherry picked from commit 96c11e410e089f207b9c0acb080bb54c57453892)
diff --git a/third_party/zlib/contrib/optimizations/inflate.c b/third_party/zlib/contrib/optimizations/inflate.c
index 81d558b..93776ac 100644
--- a/third_party/zlib/contrib/optimizations/inflate.c
+++ b/third_party/zlib/contrib/optimizations/inflate.c
@@ -771,8 +771,9 @@
if (copy > have) copy = have;
if (copy) {
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_len - state->length) <
+ state->head->extra_max) {
zmemcpy(state->head->extra + len, next,
len + copy > state->head->extra_max ?
state->head->extra_max - len : copy);
diff --git a/third_party/zlib/inflate.c b/third_party/zlib/inflate.c
index 68902e8..9057a57 100644
--- a/third_party/zlib/inflate.c
+++ b/third_party/zlib/inflate.c
@@ -760,8 +760,9 @@
if (copy > have) copy = have;
if (copy) {
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_len - state->length) <
+ state->head->extra_max) {
zmemcpy(state->head->extra + len, next,
len + copy > state->head->extra_max ?
state->head->extra_max - len : copy);