This is a note to let you know that I've just added the patch titled sctp: free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sctp-free-cmd-obj.chunk-for-the-unprocessed-sctp_cmd_reply.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat 11 Jan 2020 09:13:20 AM CET From: Xin Long <lucien.xin@xxxxxxxxx> Date: Sat, 4 Jan 2020 14:15:02 +0800 Subject: sctp: free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY From: Xin Long <lucien.xin@xxxxxxxxx> [ Upstream commit be7a7729207797476b6666f046d765bdf9630407 ] This patch is to fix a memleak caused by no place to free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY. This issue occurs when failing to process a cmd while there're still SCTP_CMD_REPLY cmds on the cmd seq with an allocated chunk in cmd->obj.chunk. So fix it by freeing cmd->obj.chunk for each SCTP_CMD_REPLY cmd left on the cmd seq when any cmd returns error. While at it, also remove 'nomem' label. Reported-by: syzbot+107c4aff5f392bf1517f@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sctp/sm_sideeffect.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -1358,8 +1358,10 @@ static int sctp_cmd_interpreter(enum sct /* Generate an INIT ACK chunk. */ new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 0); - if (!new_obj) - goto nomem; + if (!new_obj) { + error = -ENOMEM; + break; + } sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); @@ -1381,7 +1383,8 @@ static int sctp_cmd_interpreter(enum sct if (!new_obj) { if (cmd->obj.chunk) sctp_chunk_free(cmd->obj.chunk); - goto nomem; + error = -ENOMEM; + break; } sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); @@ -1428,8 +1431,10 @@ static int sctp_cmd_interpreter(enum sct /* Generate a SHUTDOWN chunk. */ new_obj = sctp_make_shutdown(asoc, chunk); - if (!new_obj) - goto nomem; + if (!new_obj) { + error = -ENOMEM; + break; + } sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(new_obj)); break; @@ -1765,11 +1770,17 @@ static int sctp_cmd_interpreter(enum sct break; } - if (error) + if (error) { + cmd = sctp_next_cmd(commands); + while (cmd) { + if (cmd->verb == SCTP_CMD_REPLY) + sctp_chunk_free(cmd->obj.chunk); + cmd = sctp_next_cmd(commands); + } break; + } } -out: /* If this is in response to a received chunk, wait until * we are done with the packet to open the queue so that we don't * send multiple packets in response to a single request. @@ -1784,7 +1795,4 @@ out: sp->data_ready_signalled = 0; return error; -nomem: - error = -ENOMEM; - goto out; } Patches currently in stable-queue which might be from lucien.xin@xxxxxxxxx are queue-5.4/sctp-free-cmd-obj.chunk-for-the-unprocessed-sctp_cmd_reply.patch