linux-stable.git/net/key, branch v3.16.52

af_key: do not use GFP_KERNEL in atomic contexts

2017-11-11T13:33:20+00:00

commit 36f41f8fc6d8aa9f8c9072d66ff7cf9055f5e69b upstream.

pfkey_broadcast() might be called from non process contexts,
we can not use GFP_KERNEL in these cases [1].

This patch partially reverts commit ba51b6be38c1 ("net: Fix RCU splat in
af_key"), only keeping the GFP_ATOMIC forcing under rcu_read_lock()
section.

[1] : syzkaller reported :

in_atomic(): 1, irqs_disabled(): 0, pid: 2932, name: syzkaller183439
3 locks held by syzkaller183439/2932:
 #0:  (&net->xfrm.xfrm_cfg_mutex){+.+.+.}, at: [] pfkey_sendmsg+0x4c8/0x9f0 net/key/af_key.c:3649
 #1:  (&pfk->dump_lock){+.+.+.}, at: [] pfkey_do_dump+0x76/0x3f0 net/key/af_key.c:293
 #2:  (&(&net->xfrm.xfrm_policy_lock)->rlock){+...+.}, at: [] spin_lock_bh include/linux/spinlock.h:304 [inline]
 #2:  (&(&net->xfrm.xfrm_policy_lock)->rlock){+...+.}, at: [] xfrm_policy_walk+0x192/0xa30 net/xfrm/xfrm_policy.c:1028
CPU: 0 PID: 2932 Comm: syzkaller183439 Not tainted 4.13.0-rc4+ #24
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 ___might_sleep+0x2b2/0x470 kernel/sched/core.c:5994
 __might_sleep+0x95/0x190 kernel/sched/core.c:5947
 slab_pre_alloc_hook mm/slab.h:416 [inline]
 slab_alloc mm/slab.c:3383 [inline]
 kmem_cache_alloc+0x24b/0x6e0 mm/slab.c:3559
 skb_clone+0x1a0/0x400 net/core/skbuff.c:1037
 pfkey_broadcast_one+0x4b2/0x6f0 net/key/af_key.c:207
 pfkey_broadcast+0x4ba/0x770 net/key/af_key.c:281
 dump_sp+0x3d6/0x500 net/key/af_key.c:2685
 xfrm_policy_walk+0x2f1/0xa30 net/xfrm/xfrm_policy.c:1042
 pfkey_dump_sp+0x42/0x50 net/key/af_key.c:2695
 pfkey_do_dump+0xaa/0x3f0 net/key/af_key.c:299
 pfkey_spddump+0x1a0/0x210 net/key/af_key.c:2722
 pfkey_process+0x606/0x710 net/key/af_key.c:2814
 pfkey_sendmsg+0x4d6/0x9f0 net/key/af_key.c:3650
sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 ___sys_sendmsg+0x755/0x890 net/socket.c:2035
 __sys_sendmsg+0xe5/0x210 net/socket.c:2069
 SYSC_sendmsg net/socket.c:2080 [inline]
 SyS_sendmsg+0x2d/0x50 net/socket.c:2076
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x445d79
RSP: 002b:00007f32447c1dc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445d79
RDX: 0000000000000000 RSI: 000000002023dfc8 RDI: 0000000000000008
RBP: 0000000000000086 R08: 00007f32447c2700 R09: 00007f32447c2700
R10: 00007f32447c2700 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffe33edec4f R14: 00007f32447c29c0 R15: 0000000000000000

Fixes: ba51b6be38c1 ("net: Fix RCU splat in af_key")
Signed-off-by: Eric Dumazet 
Reported-by: Dmitry Vyukov 
Cc: David Ahern 
Acked-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings

xfrm: NULL dereference on allocation failure

2017-09-15T17:30:11+00:00

commit e747f64336fc15e1c823344942923195b800aa1e upstream.

The default error code in pfkey_msg2xfrm_state() is -ENOBUFS.  We
added a new call to security_xfrm_state_alloc() which sets "err" to zero
so there several places where we can return ERR_PTR(0) if kmalloc()
fails.  The caller is expecting error pointers so it leads to a NULL
dereference.

Fixes: df71837d5024 ("[LSM-IPSec]: Security association restriction.")
Signed-off-by: Dan Carpenter 
Signed-off-by: Steffen Klassert 
Signed-off-by: Ben Hutchings

xfrm: Oops on error in pfkey_msg2xfrm_state()

2017-09-15T17:30:10+00:00

commit 1e3d0c2c70cd3edb5deed186c5f5c75f2b84a633 upstream.

There are some missing error codes here so we accidentally return NULL
instead of an error pointer.  It results in a NULL pointer dereference.

Fixes: df71837d5024 ("[LSM-IPSec]: Security association restriction.")
Signed-off-by: Dan Carpenter 
Signed-off-by: Steffen Klassert 
Signed-off-by: Ben Hutchings

af_key: Fix slab-out-of-bounds in pfkey_compile_policy.

2017-09-15T17:29:33+00:00

commit d90c902449a7561f1b1d58ba5a0d11728ce8b0b2 upstream.

The sadb_x_sec_len is stored in the unit 'byte divided by eight'.
So we have to multiply this value by eight before we can do
size checks. Otherwise we may get a slab-out-of-bounds when
we memcpy the user sec_ctx.

Fixes: df71837d502 ("[LSM-IPSec]: Security association restriction.")
Reported-by: Andrey Konovalov 
Tested-by: Andrey Konovalov 
Signed-off-by: Steffen Klassert 
Signed-off-by: Ben Hutchings

af_key: Add lock to key dump

2017-07-18T17:40:29+00:00

commit 89e357d83c06b6fac581c3ca7f0ee3ae7e67109e upstream.

A dump may come in the middle of another dump, modifying its dump
structure members. This race condition will result in NULL pointer
dereference in kernel. So add a lock to prevent that race.

Fixes: 83321d6b9872 ("[AF_KEY]: Dump SA/SP entries non-atomically")
Signed-off-by: Yuejie Shi 
Signed-off-by: Steffen Klassert 
Signed-off-by: Ben Hutchings

net: Fix RCU splat in af_key

2015-09-03T12:30:00+00:00

commit ba51b6be38c122f7dab40965b4397aaf6188a464 upstream.

Hit the following splat testing VRF change for ipsec:

[  113.475692] ===============================
[  113.476194] [ INFO: suspicious RCU usage. ]
[  113.476667] 4.2.0-rc6-1+deb7u2+clUNRELEASED #3.2.65-1+deb7u2+clUNRELEASED Not tainted
[  113.477545] -------------------------------
[  113.478013] /work/monster-14/dsa/kernel.git/include/linux/rcupdate.h:568 Illegal context switch in RCU read-side critical section!
[  113.479288]
[  113.479288] other info that might help us debug this:
[  113.479288]
[  113.480207]
[  113.480207] rcu_scheduler_active = 1, debug_locks = 1
[  113.480931] 2 locks held by setkey/6829:
[  113.481371]  #0:  (&net->xfrm.xfrm_cfg_mutex){+.+.+.}, at: [] pfkey_sendmsg+0xfb/0x213
[  113.482509]  #1:  (rcu_read_lock){......}, at: [] rcu_read_lock+0x0/0x6e
[  113.483509]
[  113.483509] stack backtrace:
[  113.484041] CPU: 0 PID: 6829 Comm: setkey Not tainted 4.2.0-rc6-1+deb7u2+clUNRELEASED #3.2.65-1+deb7u2+clUNRELEASED
[  113.485422] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014
[  113.486845]  0000000000000001 ffff88001d4c7a98 ffffffff81518af2 ffffffff81086962
[  113.487732]  ffff88001d538480 ffff88001d4c7ac8 ffffffff8107ae75 ffffffff8180a154
[  113.488628]  0000000000000b30 0000000000000000 00000000000000d0 ffff88001d4c7ad8
[  113.489525] Call Trace:
[  113.489813]  [] dump_stack+0x4c/0x65
[  113.490389]  [] ? console_unlock+0x3d6/0x405
[  113.491039]  [] lockdep_rcu_suspicious+0xfa/0x103
[  113.491735]  [] rcu_preempt_sleep_check+0x45/0x47
[  113.492442]  [] ___might_sleep+0x19/0x1c8
[  113.493077]  [] __might_sleep+0x6c/0x82
[  113.493681]  [] cache_alloc_debugcheck_before.isra.50+0x1d/0x24
[  113.494508]  [] kmem_cache_alloc+0x31/0x18f
[  113.495149]  [] skb_clone+0x64/0x80
[  113.495712]  [] pfkey_broadcast_one+0x3d/0xff
[  113.496380]  [] pfkey_broadcast+0xb5/0x11e
[  113.497024]  [] pfkey_register+0x191/0x1b1
[  113.497653]  [] pfkey_process+0x162/0x17e
[  113.498274]  [] pfkey_sendmsg+0x109/0x213

In pfkey_sendmsg the net mutex is taken and then pfkey_broadcast takes
the RCU lock.

Since pfkey_broadcast takes the RCU lock the allocation argument is
pointless since GFP_ATOMIC must be used between the rcu_read_{,un}lock.
The one call outside of rcu can be done with GFP_KERNEL.

Fixes: 7f6b9dbd5afbd ("af_key: locking change")
Signed-off-by: David Ahern 
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Luis Henriques

af_key: Replace comma with semicolon

2014-05-31T00:48:58+00:00

This patch replaces a comma between expression statements by a semicolon.

A simplified version of the semantic patch that performs this
transformation is as follows:

// 
@r@
expression e1,e2,e;
type T;
identifier i;
@@

 e1
-,
+;
 e2;
// 

Signed-off-by: Himangi Saraogi 
Acked-by: Julia Lawall 
Signed-off-by: David S. Miller

xfrm: Remove useless xfrm_audit struct.

2014-04-23T06:21:04+00:00

Commit f1370cc4 "xfrm: Remove useless secid field from xfrm_audit." changed
"struct xfrm_audit" to have either
{ audit_get_loginuid(current) / audit_get_sessionid(current) } or
{ INVALID_UID / -1 } pair.

This means that we can represent "struct xfrm_audit" as "bool".
This patch replaces "struct xfrm_audit" argument with "bool".

Signed-off-by: Tetsuo Handa 
Signed-off-by: Steffen Klassert

xfrm: Remove useless secid field from xfrm_audit.

2014-04-22T08:47:53+00:00

It seems to me that commit ab5f5e8b "[XFRM]: xfrm audit calls" is doing
something strange at xfrm_audit_helper_usrinfo().
If secid != 0 && security_secid_to_secctx(secid) != 0, the caller calls
audit_log_task_context() which basically does
secid != 0 && security_secid_to_secctx(secid) == 0 case
except that secid is obtained from current thread's context.

Oh, what happens if secid passed to xfrm_audit_helper_usrinfo() was
obtained from other thread's context? It might audit current thread's
context rather than other thread's context if security_secid_to_secctx()
in xfrm_audit_helper_usrinfo() failed for some reason.

Then, are all the caller of xfrm_audit_helper_usrinfo() passing either
secid obtained from current thread's context or secid == 0?
It seems to me that they are.

If I didn't miss something, we don't need to pass secid to
xfrm_audit_helper_usrinfo() because audit_log_task_context() will
obtain secid from current thread's context.

Signed-off-by: Tetsuo Handa 
Signed-off-by: Steffen Klassert

net: Fix use after free by removing length arg from sk_data_ready callbacks.

2014-04-11T20:15:36+00:00

Several spots in the kernel perform a sequence like:

	skb_queue_tail(&sk->s_receive_queue, skb);
	sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up.  So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument.  And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller