diff options
| author | Daniel Borkmann <dborkman@redhat.com> | 2014-06-18 23:46:31 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-06-19 21:30:19 -0700 |
| commit | 24599e61b7552673dd85971cf5a35369cd8c119e (patch) | |
| tree | 969fd9c03baf1de6f39cd7057adf78eace68936d | |
| parent | 40c1deaf6c2b42d7ee4e604ba5793cf9da292d96 (diff) | |
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>
| -rw-r--r-- | net/sctp/sysctl.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index cc12162ba091..12c7e01c2677 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -447,8 +447,7 @@ static int proc_sctp_do_auth(struct ctl_table *ctl, int write, tbl.data = &net->sctp.auth_enable; ret = proc_dointvec(&tbl, write, buffer, lenp, ppos); - - if (write) { + if (write && ret == 0) { struct sock *sk = net->sctp.ctl_sock; net->sctp.auth_enable = new_value; |