3.16.83-rc1 review patch. If anyone has any objections, please let me know.
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From: Xin Long lucien.xin@gmail.com
commit be7a7729207797476b6666f046d765bdf9630407 upstream.
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: Ben Hutchings ben@decadent.org.uk --- 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 @@ -1327,8 +1327,10 @@ static int sctp_cmd_interpreter(sctp_eve /* 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)); @@ -1350,7 +1352,8 @@ static int sctp_cmd_interpreter(sctp_eve 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)); @@ -1397,8 +1400,10 @@ static int sctp_cmd_interpreter(sctp_eve
/* 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; @@ -1727,11 +1732,17 @@ static int sctp_cmd_interpreter(sctp_eve 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. @@ -1742,8 +1753,5 @@ out: } else if (local_cork) error = sctp_outq_uncork(&asoc->outqueue); return error; -nomem: - error = -ENOMEM; - goto out; }