Re: [PATCH] sctp: fix memory leak in sctp_datamsg_from_user() when copy from user space fails

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 11/22/2012 08:21 AM, Tommi Rantala wrote:
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@xxxxxxxxx>
---
  net/sctp/chunk.c |    7 +++++--
  1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index 7c2df9c..d241ef5 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -284,7 +284,7 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
  			goto errout;
  		err = sctp_user_addto_chunk(chunk, offset, len, msgh->msg_iov);
  		if (err < 0)
-			goto errout;
+			goto errout_chunk_put;

  		offset += len;

@@ -324,7 +324,7 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
  		__skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr
  			   - (__u8 *)chunk->skb->data);
  		if (err < 0)
-			goto errout;
+			goto errout_chunk_put;

  		sctp_datamsg_assign(msg, chunk);
  		list_add_tail(&chunk->frag_list, &msg->chunks);
@@ -332,6 +332,9 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,

  	return msg;

+errout_chunk_put:
+	sctp_chunk_put(chunk);
+
  errout:
  	list_for_each_safe(pos, temp, &msg->chunks) {
  		list_del_init(pos);


Should be using sctp_chunk_free().  Good find.

-vlad
--
To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Networking Development]     [Linux OMAP]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux