sctp: fix memory leak in sctp_datamsg_from_user() when copy from user space fails
Trinity (the syscall fuzzer) discovered a memory leak in SCTP,
reproducible e.g. with the sendto() syscall by passing invalid
user space pointer in the second argument:
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
int main(void)
{
int fd;
struct sockaddr_in sa;
fd = socket(AF_INET, SOCK_STREAM, 132 /*IPPROTO_SCTP*/);
if (fd < 0)
return 1;
memset(&sa, 0, sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = inet_addr("127.0.0.1");
sa.sin_port = htons(11111);
sendto(fd, NULL, 1, 0, (struct sockaddr *)&sa, sizeof(sa));
return 0;
}
As far as I can tell, the leak has been around since ~2003.
Signed-off-by: Tommi Rantala <tt.rantala@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index 7c2df9c..f2aebdb 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -284,7 +284,7 @@
goto errout;
err = sctp_user_addto_chunk(chunk, offset, len, msgh->msg_iov);
if (err < 0)
- goto errout;
+ goto errout_chunk_free;
offset += len;
@@ -324,7 +324,7 @@
__skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr
- (__u8 *)chunk->skb->data);
if (err < 0)
- goto errout;
+ goto errout_chunk_free;
sctp_datamsg_assign(msg, chunk);
list_add_tail(&chunk->frag_list, &msg->chunks);
@@ -332,6 +332,9 @@
return msg;
+errout_chunk_free:
+ sctp_chunk_free(chunk);
+
errout:
list_for_each_safe(pos, temp, &msg->chunks) {
list_del_init(pos);