From: Xin Long lucien.xin@gmail.com
[ 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@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xin Long lucien.xin@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- net/sctp/sm_sideeffect.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index de8a82b..0234a64 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -1373,8 +1373,10 @@ static int sctp_cmd_interpreter(enum sctp_event event_type, /* 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)); @@ -1396,7 +1398,8 @@ static int sctp_cmd_interpreter(enum sctp_event event_type, 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)); @@ -1443,8 +1446,10 @@ static int sctp_cmd_interpreter(enum sctp_event event_type,
/* 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; @@ -1780,11 +1785,17 @@ static int sctp_cmd_interpreter(enum sctp_event event_type, 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. @@ -1799,7 +1810,4 @@ static int sctp_cmd_interpreter(enum sctp_event event_type, sp->data_ready_signalled = 0;
return error; -nomem: - error = -ENOMEM; - goto out; }