linux-stable.git/net, branch v4.9.151

sunrpc: use-after-free in svc_process_common()

2019-01-16T21:12:33+00:00

commit d4b09acf924b84bae77cad090a9d108e70b43643 upstream.

if node have NFSv41+ mounts inside several net namespaces
it can lead to use-after-free in svc_process_common()

svc_process_common()
        /* Setup reply header */
        rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE

svc_process_common() can use incorrect rqstp->rq_xprt,
its caller function bc_svc_process() takes it from serv->sv_bc_xprt.
The problem is that serv is global structure but sv_bc_xprt
is assigned per-netnamespace.

According to Trond, the whole "let's set up rqstp->rq_xprt
for the back channel" is nothing but a giant hack in order
to work around the fact that svc_process_common() uses it
to find the xpt_ops, and perform a couple of (meaningless
for the back channel) tests of xpt_flags.

All we really need in svc_process_common() is to be able to run
rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr()

Bruce J Fields points that this xpo_prep_reply_hdr() call
is an awfully roundabout way just to do "svc_putnl(resv, 0);"
in the tcp case.

This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(),
now it calls svc_process_common() with rqstp->rq_xprt = NULL.

To adjust reply header svc_process_common() just check
rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case.

To handle rqstp->rq_xprt = NULL case in functions called from
svc_process_common() patch intruduces net namespace pointer
svc_rqst->rq_bc_net and adjust SVC_NET() definition.
Some other function was also adopted to properly handle described case.

Signed-off-by: Vasily Averin 
Cc: stable@vger.kernel.org
Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup")
Signed-off-by: J. Bruce Fields 
v2: - added lost extern svc_tcp_prep_reply_hdr()
    - dropped trace_svc_process() changes
    - context fixes in svc_process_common()
Signed-off-by: Vasily Averin 
Signed-off-by: Greg Kroah-Hartman

9p/net: put a lower bound on msize

2019-01-13T09:03:52+00:00

commit 574d356b7a02c7e1b01a1d9cba8a26b3c2888f45 upstream.

If the requested msize is too small (either from command line argument
or from the server version reply), we won't get any work done.
If it's *really* too small, nothing will work, and this got caught by
syzbot recently (on a new kmem_cache_create_usercopy() call)

Just set a minimum msize to 4k in both code paths, until someone
complains they have a use-case for a smaller msize.

We need to check in both mount option and server reply individually
because the msize for the first version request would be unchecked
with just a global check on clnt->msize.

Link: http://lkml.kernel.org/r/1541407968-31350-1-git-send-email-asmadeus@codewreck.org
Reported-by: syzbot+0c1d61e4db7db94102ca@syzkaller.appspotmail.com
Signed-off-by: Dominique Martinet 
Cc: Eric Van Hensbergen 
Cc: Latchesar Ionkov 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

sunrpc: use SVC_NET() in svcauth_gss_* functions

2019-01-13T09:03:51+00:00

commit b8be5674fa9a6f3677865ea93f7803c4212f3e10 upstream.

Signed-off-by: Vasily Averin 
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

sunrpc: fix cache_head leak due to queued request

2019-01-13T09:03:51+00:00

commit 4ecd55ea074217473f94cfee21bb72864d39f8d7 upstream.

After commit d202cce8963d, an expired cache_head can be removed from the
cache_detail's hash.

However, the expired cache_head may be waiting for a reply from a
previously submitted request. Such a cache_head has an increased
refcounter and therefore it won't be freed after cache_put(freeme).

Because the cache_head was removed from the hash it cannot be found
during cache_clean() and can be leaked forever, together with stalled
cache_request and other taken resources.

In our case we noticed it because an entry in the export cache was
holding a reference on a filesystem.

Fixes d202cce8963d ("sunrpc: never return expired entries in sunrpc_cache_lookup")
Cc: Pavel Tikhomirov 
Cc: stable@kernel.org # 2.6.35
Signed-off-by: Vasily Averin 
Reviewed-by: NeilBrown 
Signed-off-by: J. Bruce Fields 
Signed-off-by: Greg Kroah-Hartman

libceph: fix CEPH_FEATURE_CEPHX_V2 check in calc_signature()

2019-01-13T09:03:50+00:00

Upstream commit cc255c76c70f ("libceph: implement CEPHX_V2 calculation
mode") was adjusted incorrectly: CEPH_FEATURE_CEPHX_V2 if condition got
inverted, thus breaking 4.9.144 and later kernels for all setups that
use cephx.

Cc: Ben Hutchings 
Signed-off-by: Ilya Dryomov

SUNRPC: Fix a race with XPRT_CONNECTING

2019-01-13T09:03:50+00:00

[ Upstream commit cf76785d30712d90185455e752337acdb53d2a5d ]

Ensure that we clear XPRT_CONNECTING before releasing the XPRT_LOCK so that
we don't have races between the (asynchronous) socket setup code and
tasks in xprt_connect().

Signed-off-by: Trond Myklebust 
Tested-by: Chuck Lever 
Signed-off-by: Sasha Levin

netfilter: ipset: do not call ipset_nest_end after nla_nest_cancel

2019-01-13T09:03:48+00:00

[ Upstream commit 708abf74dd87f8640871b814faa195fb5970b0e3 ]

In the error handling block, nla_nest_cancel(skb, atd) is called to
cancel the nest operation. But then, ipset_nest_end(skb, atd) is
unexpected called to end the nest operation. This patch calls the
ipset_nest_end only on the branch that nla_nest_cancel is not called.

Fixes: 45040978c899 ("netfilter: ipset: Fix set:list type crash when flush/dump set in parallel")
Signed-off-by: Pan Bian 
Signed-off-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: seqadj: re-load tcp header pointer after possible head reallocation

2019-01-13T09:03:48+00:00

[ Upstream commit 530aad77010b81526586dfc09130ec875cd084e4 ]

When adjusting sack block sequence numbers, skb_make_writable() gets
called to make sure tcp options are all in the linear area, and buffer
is not shared.

This can cause tcp header pointer to get reallocated, so we must
reaload it to avoid memory corruption.

This bug pre-dates git history.

Reported-by: Neel Mehta 
Reported-by: Shane Huntley 
Reported-by: Heather Adkins 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

xfrm: Fix bucket count reported to userspace

2019-01-13T09:03:48+00:00

[ Upstream commit ca92e173ab34a4f7fc4128bd372bd96f1af6f507 ]

sadhcnt is reported by `ip -s xfrm state count` as "buckets count", not the
hash mask.

Fixes: 28d8909bc790 ("[XFRM]: Export SAD info.")
Signed-off-by: Benjamin Poirier 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin

sock: Make sock->sk_stamp thread-safe

2019-01-09T15:16:41+00:00

[ Upstream commit 3a0ed3e9619738067214871e9cb826fa23b2ddb9 ]

Al Viro mentioned (Message-ID
<20170626041334.GZ10672@ZenIV.linux.org.uk>)
that there is probably a race condition
lurking in accesses of sk_stamp on 32-bit machines.

sock->sk_stamp is of type ktime_t which is always an s64.
On a 32 bit architecture, we might run into situations of
unsafe access as the access to the field becomes non atomic.

Use seqlocks for synchronization.
This allows us to avoid using spinlocks for readers as
readers do not need mutual exclusion.

Another approach to solve this is to require sk_lock for all
modifications of the timestamps. The current approach allows
for timestamps to have their own lock: sk_stamp_lock.
This allows for the patch to not compete with already
existing critical sections, and side effects are limited
to the paths in the patch.

The addition of the new field maintains the data locality
optimizations from
commit 9115e8cd2a0c ("net: reorganize struct sock for better data
locality")

Note that all the instances of the sk_stamp accesses
are either through the ioctl or the syscall recvmsg.

Signed-off-by: Deepa Dinamani 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman