Herbert Xu b377c453b3 ipsec: Fix aborted xfrm policy dump crash
commit 1137b5e2529a8f5ca8ee709288ecba3e68044df2 upstream.

An independent security researcher, Mohamed Ghannam, has reported
this vulnerability to Beyond Security's SecuriTeam Secure Disclosure
program.

The xfrm_dump_policy_done function expects xfrm_dump_policy to
have been called at least once or it will crash.  This can be
triggered if a dump fails because the target socket's receive
buffer is full.

This patch fixes it by using the cb->start mechanism to ensure that
the initialisation is always done regardless of the buffer situation.

Fixes: 12a169e7d8f4 ("ipsec: Put dumpers on the dump list")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-05 11:22:49 +01:00
..
2017-11-15 17:13:11 +01:00
2015-11-23 14:56:15 -05:00
2015-10-07 04:27:43 -07:00
2015-10-21 00:49:24 +02:00
2017-10-08 10:14:18 +02:00