From 7a26092a9e21f1e0dc3cad69a580a7e2c7822ad0 Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Sun, 16 Aug 2020 11:34:35 +0200
Subject: [PATCH] Curl_easy: remember last connection by id, not by pointer
CVE-2020-8231
Bug: https://curl.haxx.se/docs/CVE-2020-8231.html
Reported-by: Marc Aldorasi
Closes #5824
Upstream-commit: 3c9e021f86872baae412a427e807fbfa2f3e8a22
Signed-off-by: Kamil Dudka <kdudka@redhat.com>
---
lib/connect.c | 19 ++++++++++---------
lib/easy.c | 3 +--
lib/multi.c | 5 +++--
lib/url.c | 2 +-
lib/urldata.h | 2 +-
5 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/lib/connect.c b/lib/connect.c
index 41f2202..f724646 100644
--- a/lib/connect.c
+++ b/lib/connect.c
@@ -1214,15 +1214,15 @@ CURLcode Curl_connecthost(struct connectdata *conn, /* context */
}
struct connfind {
- struct connectdata *tofind;
- bool found;
+ long id_tofind;
+ struct connectdata *found;
};
static int conn_is_conn(struct connectdata *conn, void *param)
{
struct connfind *f = (struct connfind *)param;
- if(conn == f->tofind) {
- f->found = TRUE;
+ if(conn->connection_id == f->id_tofind) {
+ f->found = conn;
return 1;
}
return 0;
@@ -1244,21 +1244,22 @@ curl_socket_t Curl_getconnectinfo(struct Curl_easy *data,
* - that is associated with a multi handle, and whose connection
* was detached with CURLOPT_CONNECT_ONLY
*/
- if(data->state.lastconnect && (data->multi_easy || data->multi)) {
- struct connectdata *c = data->state.lastconnect;
+ if((data->state.lastconnect_id != -1) && (data->multi_easy || data->multi)) {
+ struct connectdata *c;
struct connfind find;
- find.tofind = data->state.lastconnect;
- find.found = FALSE;
+ find.id_tofind = data->state.lastconnect_id;
+ find.found = NULL;
Curl_conncache_foreach(data, data->multi_easy?
&data->multi_easy->conn_cache:
&data->multi->conn_cache, &find, conn_is_conn);
if(!find.found) {
- data->state.lastconnect = NULL;
+ data->state.lastconnect_id = -1;
return CURL_SOCKET_BAD;
}
+ c = find.found;
if(connp) {
/* only store this if the caller cares for it */
*connp = c;
diff --git a/lib/easy.c b/lib/easy.c
index 027d0be..fe61cdd 100644
--- a/lib/easy.c
+++ b/lib/easy.c
@@ -919,8 +919,7 @@ struct Curl_easy *curl_easy_duphandle(struct Curl_easy *data)
/* the connection cache is setup on demand */
outcurl->state.conn_cache = NULL;
-
- outcurl->state.lastconnect = NULL;
+ outcurl->state.lastconnect_id = -1;
outcurl->progress.flags = data->progress.flags;
outcurl->progress.callback = data->progress.callback;
diff --git a/lib/multi.c b/lib/multi.c
index 0caf943..0f57fd5 100644
--- a/lib/multi.c
+++ b/lib/multi.c
@@ -427,6 +427,7 @@ CURLMcode curl_multi_add_handle(struct Curl_multi *multi,
data->state.conn_cache = &data->share->conn_cache;
else
data->state.conn_cache = &multi->conn_cache;
+ data->state.lastconnect_id = -1;
#ifdef USE_LIBPSL
/* Do the same for PSL. */
@@ -644,11 +645,11 @@ static CURLcode multi_done(struct connectdata **connp,
/* the connection is no longer in use by this transfer */
if(Curl_conncache_return_conn(conn)) {
/* remember the most recently used connection */
- data->state.lastconnect = conn;
+ data->state.lastconnect_id = conn->connection_id;
infof(data, "%s\n", buffer);
}
else
- data->state.lastconnect = NULL;
+ data->state.lastconnect_id = -1;
}
*connp = NULL; /* to make the caller of this function better detect that
diff --git a/lib/url.c b/lib/url.c
index dcc6cc8..d65d17d 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -592,7 +592,7 @@ CURLcode Curl_open(struct Curl_easy **curl)
Curl_initinfo(data);
/* most recent connection is not yet defined */
- data->state.lastconnect = NULL;
+ data->state.lastconnect_id = -1;
data->progress.flags |= PGRS_HIDE;
data->state.current_speed = -1; /* init to negative == impossible */
diff --git a/lib/urldata.h b/lib/urldata.h
index 67db3b2..4b70cc5 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1219,7 +1219,7 @@ struct UrlState {
/* buffers to store authentication data in, as parsed from input options */
struct curltime keeps_speed; /* for the progress meter really */
- struct connectdata *lastconnect; /* The last connection, NULL if undefined */
+ long lastconnect_id; /* The last connection, -1 if undefined */
char *headerbuff; /* allocated buffer to store headers in */
size_t headersize; /* size of the allocation */
--
2.25.4