BUG/MEDIUM: http: Prevent replace-header from overwriting a buffer
This is the same fix as which concerning the redirect rules (0d94576c).
The buffer used to expand the <replace-fmt> argument must be protected to
prevent it being overwritten during build_logline() execution (the function used
to expand the format string).
This patch should be backported in 1.7, 1.6 and 1.5. It relies on commit b686afd
("MINOR: chunks: implement a simple dynamic allocator for trash buffers") for
the trash allocator, which has to be backported as well.
diff --git a/src/proto_http.c b/src/proto_http.c
index 80ba566..3d8005e 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -3419,13 +3419,22 @@
struct list *fmt, struct my_regex *re,
int action)
{
- struct chunk *replace = get_trash_chunk();
+ struct chunk *replace;
+ int ret = -1;
+
+ replace = alloc_trash_chunk();
+ if (!replace)
+ goto leave;
replace->len = build_logline(s, replace->str, replace->size, fmt);
if (replace->len >= replace->size - 1)
- return -1;
+ goto leave;
+
+ ret = http_transform_header_str(s, msg, name, name_len, replace->str, re, action);
- return http_transform_header_str(s, msg, name, name_len, replace->str, re, action);
+ leave:
+ free_trash_chunk(replace);
+ return ret;
}
/* Executes the http-request rules <rules> for stream <s>, proxy <px> and