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Revision 64b4c411a6c7a5f27555bfc2d6310b87bde3db67 authored by Andrew Morton on 21 October 2022, 04:19:22 UTC, committed by Andrew Morton on 28 October 2022, 20:37:22 UTC 
ipc/msg.c: fix percpu_counter use after free
 
These percpu counters are referenced in free_ipcs->freeque, so destroy
them later.

Fixes: 72d1e611082e ("ipc/msg: mitigate the lock contention with percpu counter")
Reported-by: syzbot+96e659d35b9d6b541152@syzkaller.appspotmail.com
Tested-by: Mark Rutland <mark.rutland@arm.com>
Cc: Jiebin Sun <jiebin.sun@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1 parent 27d676a
Raw File
ratelimit_types.h 
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_RATELIMIT_TYPES_H
#define _LINUX_RATELIMIT_TYPES_H

#include <linux/bits.h>
#include <linux/param.h>
#include <linux/spinlock_types_raw.h>

#define DEFAULT_RATELIMIT_INTERVAL	(5 * HZ)
#define DEFAULT_RATELIMIT_BURST		10

/* issue num suppressed message on exit */
#define RATELIMIT_MSG_ON_RELEASE	BIT(0)

struct ratelimit_state {
	raw_spinlock_t	lock;		/* protect the state */

	int		interval;
	int		burst;
	int		printed;
	int		missed;
	unsigned long	begin;
	unsigned long	flags;
};

#define RATELIMIT_STATE_INIT_FLAGS(name, interval_init, burst_init, flags_init) { \
		.lock		= __RAW_SPIN_LOCK_UNLOCKED(name.lock),		  \
		.interval	= interval_init,				  \
		.burst		= burst_init,					  \
		.flags		= flags_init,					  \
	}

#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) \
	RATELIMIT_STATE_INIT_FLAGS(name, interval_init, burst_init, 0)

#define RATELIMIT_STATE_INIT_DISABLED					\
	RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)

#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init)		\
									\
	struct ratelimit_state name =					\
		RATELIMIT_STATE_INIT(name, interval_init, burst_init)	\

extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
#define __ratelimit(state) ___ratelimit(state, __func__)

#endif /* _LINUX_RATELIMIT_TYPES_H */
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