David Howells 8d9c4a9b86 rxrpc: Fix trace-after-put looking at the put peer record ... commit 55f6c98e36 upstream. rxrpc_put_peer() calls trace_rxrpc_peer() after it has done the decrement of the refcount - which looks at the debug_id in the peer record. But unless the refcount was reduced to zero, we no longer have the right to look in the record and, indeed, it may be deleted by some other thread. Fix this by getting the debug_id out before decrementing the refcount and then passing that into the tracepoint. This can cause the following symptoms: BUG: KASAN: use-after-free in __rxrpc_put_peer net/rxrpc/peer_object.c:411 [inline] BUG: KASAN: use-after-free in rxrpc_put_peer+0x685/0x6a0 net/rxrpc/peer_object.c:435 Read of size 8 at addr ffff888097ec0058 by task syz-executor823/24216 Fixes: 1159d4b496 ("rxrpc: Add a tracepoint to track rxrpc_peer refcounting") Reported-by: syzbot+b9be979c55f2bea8ed30@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2019-11-06 13:06:24 +01:00
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events	rxrpc: Fix trace-after-put looking at the put peer record	2019-11-06 13:06:24 +01:00
bpf_probe.h	bpf: introduce BPF_RAW_TRACEPOINT	2018-03-28 22:55:19 +02:00
define_trace.h	bpf: introduce BPF_RAW_TRACEPOINT	2018-03-28 22:55:19 +02:00
perf.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2017-11-04 09:26:51 +09:00
syscall.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
trace_events.h	tracing: Prevent further users of zero size static arrays in trace events	2018-05-29 08:29:13 -04:00