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:

As far as I can tell, the leak has been around since ~2003.

Signed-off-by Tommi Rantala <[email protected]>

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 <[email protected]>

---
  net/sctp/chunk.c |    7 +++++--
  1 file changed, 5 insertions(+), 2 deletions(-)

net/sctp/chunk.c +2 -2

index 7c2df9c..d241ef5 100644
@@ -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);

Should be using sctp_chunk_free(). Good find.

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 <[email protected]>

---
  net/sctp/chunk.c |    7 +++++--
  1 file changed, 5 insertions(+), 2 deletions(-)

net/sctp/chunk.c +5 -2

index 7c2df9c..f2aebdb 100644
@@ -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_free;
 
  		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_free;
 
  		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_free:
+	sctp_chunk_free(chunk);
+
  errout:
  	list_for_each_safe(pos, temp, &msg->chunks) {
  		list_del_init(pos);

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:

As far as I can tell, the leak has been around since ~2003.

Signed-off-by Tommi Rantala <[email protected]>

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 <[email protected]>

---
 net/sctp/chunk.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

net/sctp/chunk.c +5 -2

index 7c2df9c..d241ef5 100644
@@ -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);

Signature · 6 lines

1.7.9.5

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