Revision 321027c1fe77f892f4ea07846aeae08cefbbb290 authored by Peter Zijlstra on 11 January 2017, 20:09:50 UTC, committed by Ingo Molnar on 14 January 2017, 09:56:11 UTC
Di Shen reported a race between two concurrent sys_perf_event_open()
calls where both try and move the same pre-existing software group
into a hardware context.
The problem is exactly that described in commit:
f63a8daa5812 ("perf: Fix event->ctx locking")
... where, while we wait for a ctx->mutex acquisition, the event->ctx
relation can have changed under us.
That very same commit failed to recognise sys_perf_event_context() as an
external access vector to the events and thereby didn't apply the
established locking rules correctly.
So while one sys_perf_event_open() call is stuck waiting on
mutex_lock_double(), the other (which owns said locks) moves the group
about. So by the time the former sys_perf_event_open() acquires the
locks, the context we've acquired is stale (and possibly dead).
Apply the established locking rules as per perf_event_ctx_lock_nested()
to the mutex_lock_double() for the 'move_group' case. This obviously means
we need to validate state after we acquire the locks.
Reported-by: Di Shen (Keen Lab)
Tested-by: John Dias <joaodias@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Min Chong <mchong@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: f63a8daa5812 ("perf: Fix event->ctx locking")
Link: http://lkml.kernel.org/r/20170106131444.GZ3174@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1 parent 63cae12
tcrypt.h
/*
* Quick & dirty crypto testing module.
*
* This will only exist until we have a better testing mechanism
* (e.g. a char device).
*
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
* Copyright (c) 2002 Jean-Francois Dive <jef@linuxbe.org>
* Copyright (c) 2007 Nokia Siemens Networks
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#ifndef _CRYPTO_TCRYPT_H
#define _CRYPTO_TCRYPT_H
struct cipher_speed_template {
const char *key;
unsigned int klen;
};
struct aead_speed_template {
const char *key;
unsigned int klen;
};
struct hash_speed {
unsigned int blen; /* buffer length */
unsigned int plen; /* per-update length */
unsigned int klen; /* key length */
};
/*
* DES test vectors.
*/
#define DES3_SPEED_VECTORS 1
static struct cipher_speed_template des3_speed_template[] = {
{
.key = "\x01\x23\x45\x67\x89\xab\xcd\xef"
"\x55\x55\x55\x55\x55\x55\x55\x55"
"\xfe\xdc\xba\x98\x76\x54\x32\x10",
.klen = 24,
}
};
/*
* Cipher speed tests
*/
static u8 speed_template_8[] = {8, 0};
static u8 speed_template_24[] = {24, 0};
static u8 speed_template_8_16[] = {8, 16, 0};
static u8 speed_template_8_32[] = {8, 32, 0};
static u8 speed_template_16_32[] = {16, 32, 0};
static u8 speed_template_16_24_32[] = {16, 24, 32, 0};
static u8 speed_template_20_28_36[] = {20, 28, 36, 0};
static u8 speed_template_32_40_48[] = {32, 40, 48, 0};
static u8 speed_template_32_48[] = {32, 48, 0};
static u8 speed_template_32_48_64[] = {32, 48, 64, 0};
static u8 speed_template_32_64[] = {32, 64, 0};
static u8 speed_template_32[] = {32, 0};
/*
* AEAD speed tests
*/
static u8 aead_speed_template_19[] = {19, 0};
static u8 aead_speed_template_20[] = {20, 0};
static u8 aead_speed_template_36[] = {36, 0};
/*
* Digest speed tests
*/
static struct hash_speed generic_hash_speed_template[] = {
{ .blen = 16, .plen = 16, },
{ .blen = 64, .plen = 16, },
{ .blen = 64, .plen = 64, },
{ .blen = 256, .plen = 16, },
{ .blen = 256, .plen = 64, },
{ .blen = 256, .plen = 256, },
{ .blen = 1024, .plen = 16, },
{ .blen = 1024, .plen = 256, },
{ .blen = 1024, .plen = 1024, },
{ .blen = 2048, .plen = 16, },
{ .blen = 2048, .plen = 256, },
{ .blen = 2048, .plen = 1024, },
{ .blen = 2048, .plen = 2048, },
{ .blen = 4096, .plen = 16, },
{ .blen = 4096, .plen = 256, },
{ .blen = 4096, .plen = 1024, },
{ .blen = 4096, .plen = 4096, },
{ .blen = 8192, .plen = 16, },
{ .blen = 8192, .plen = 256, },
{ .blen = 8192, .plen = 1024, },
{ .blen = 8192, .plen = 4096, },
{ .blen = 8192, .plen = 8192, },
/* End marker */
{ .blen = 0, .plen = 0, }
};
static struct hash_speed hash_speed_template_16[] = {
{ .blen = 16, .plen = 16, .klen = 16, },
{ .blen = 64, .plen = 16, .klen = 16, },
{ .blen = 64, .plen = 64, .klen = 16, },
{ .blen = 256, .plen = 16, .klen = 16, },
{ .blen = 256, .plen = 64, .klen = 16, },
{ .blen = 256, .plen = 256, .klen = 16, },
{ .blen = 1024, .plen = 16, .klen = 16, },
{ .blen = 1024, .plen = 256, .klen = 16, },
{ .blen = 1024, .plen = 1024, .klen = 16, },
{ .blen = 2048, .plen = 16, .klen = 16, },
{ .blen = 2048, .plen = 256, .klen = 16, },
{ .blen = 2048, .plen = 1024, .klen = 16, },
{ .blen = 2048, .plen = 2048, .klen = 16, },
{ .blen = 4096, .plen = 16, .klen = 16, },
{ .blen = 4096, .plen = 256, .klen = 16, },
{ .blen = 4096, .plen = 1024, .klen = 16, },
{ .blen = 4096, .plen = 4096, .klen = 16, },
{ .blen = 8192, .plen = 16, .klen = 16, },
{ .blen = 8192, .plen = 256, .klen = 16, },
{ .blen = 8192, .plen = 1024, .klen = 16, },
{ .blen = 8192, .plen = 4096, .klen = 16, },
{ .blen = 8192, .plen = 8192, .klen = 16, },
/* End marker */
{ .blen = 0, .plen = 0, .klen = 0, }
};
static struct hash_speed poly1305_speed_template[] = {
{ .blen = 96, .plen = 16, },
{ .blen = 96, .plen = 32, },
{ .blen = 96, .plen = 96, },
{ .blen = 288, .plen = 16, },
{ .blen = 288, .plen = 32, },
{ .blen = 288, .plen = 288, },
{ .blen = 1056, .plen = 32, },
{ .blen = 1056, .plen = 1056, },
{ .blen = 2080, .plen = 32, },
{ .blen = 2080, .plen = 2080, },
{ .blen = 4128, .plen = 4128, },
{ .blen = 8224, .plen = 8224, },
/* End marker */
{ .blen = 0, .plen = 0, }
};
#endif /* _CRYPTO_TCRYPT_H */
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