tree 969fd9c03baf1de6f39cd7057adf78eace68936d
parent 40c1deaf6c2b42d7ee4e604ba5793cf9da292d96
author Daniel Borkmann <dborkman@redhat.com> 1403127991 +0200
committer David S. Miller <davem@davemloft.net> 1403238619 -0700

net: sctp: check proc_dointvec result in proc_sctp_do_auth

When writing to the sysctl field net.sctp.auth_enable, it can well
be that the user buffer we handed over to proc_dointvec() via
proc_sctp_do_auth() handler contains something other than integers.

In that case, we would set an uninitialized 4-byte value from the
stack to net->sctp.auth_enable that can be leaked back when reading
the sysctl variable, and it can unintentionally turn auth_enable
on/off based on the stack content since auth_enable is interpreted
as a boolean.

Fix it up by making sure proc_dointvec() returned sucessfully.

Fixes: b14878ccb7fa ("net: sctp: cache auth_enable per endpoint")
Reported-by: Florian Westphal <fwestpha@redhat.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>