diff options
| author | Daniel Borkmann <dborkman@redhat.com> | 2014-06-18 23:46:31 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-07-28 08:00:04 -0700 |
| commit | e9013d0f0faef78f90f7bb30e722965fe992dc1e (patch) | |
| tree | b5f8853623076f5c386296bad2e9a97a96c9406f | |
| parent | 856443cb555a75b9700d3fabf5965b46337de199 (diff) | |
net: sctp: check proc_dointvec result in proc_sctp_do_auth
[ Upstream commit 24599e61b7552673dd85971cf5a35369cd8c119e ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 fe0ba7488bd..29299dcabfb 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -368,8 +368,7 @@ 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; |