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Revision 89a8640279f8bb78aaf778d1fc5c4a6778f18064 authored by David Howells on 30 October 2009, 13:13:26 UTC, committed by Linus Torvalds on 31 October 2009, 19:11:37 UTC 
NOMMU: Don't pass NULL pointers to fput() in do_mmap_pgoff()
 
Don't pass NULL pointers to fput() in the error handling paths of the NOMMU
do_mmap_pgoff() as it can't handle it.

The following can be used as a test program:

	int main() { static long long a[1024 * 1024 * 20] = { 0 }; return a;}

Without the patch, the code oopses in atomic_long_dec_and_test() as called by
fput() after the kernel complains that it can't allocate that big a chunk of
memory.  With the patch, the kernel just complains about the allocation size
and then the program segfaults during execve() as execve() can't complete the
allocation of all the new ELF program segments.

Reported-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Robin Getz <rgetz@blackfin.uclinux.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 2e2ec95
Raw File
sembuf.h 
#ifndef __ASM_GENERIC_SEMBUF_H
#define __ASM_GENERIC_SEMBUF_H

#include <asm/bitsperlong.h>

/*
 * The semid64_ds structure for x86 architecture.
 * Note extra padding because this structure is passed back and forth
 * between kernel and user space.
 *
 * semid64_ds was originally meant to be architecture specific, but
 * everyone just ended up making identical copies without specific
 * optimizations, so we may just as well all use the same one.
 *
 * 64 bit architectures typically define a 64 bit __kernel_time_t,
 * so they do not need the first two padding words.
 * On big-endian systems, the padding is in the wrong place.
 *
 * Pad space is left for:
 * - 64-bit time_t to solve y2038 problem
 * - 2 miscellaneous 32-bit values
 */
struct semid64_ds {
	struct ipc64_perm sem_perm;	/* permissions .. see ipc.h */
	__kernel_time_t	sem_otime;	/* last semop time */
#if __BITS_PER_LONG != 64
	unsigned long	__unused1;
#endif
	__kernel_time_t	sem_ctime;	/* last change time */
#if __BITS_PER_LONG != 64
	unsigned long	__unused2;
#endif
	unsigned long	sem_nsems;	/* no. of semaphores in array */
	unsigned long	__unused3;
	unsigned long	__unused4;
};

#endif /* __ASM_GENERIC_SEMBUF_H */
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