Kirill A. Shutemov 31b4beb473 ipc/shm: fix crash if CONFIG_SHMEM is not set ... Commit c01d5b3007 ("shmem: get_unmapped_area align huge page") makes use of shm_get_unmapped_area() in shm_file_operations() unconditional to CONFIG_MMU. As Tony Battersby pointed this can lead NULL-pointer dereference on machine with CONFIG_MMU=y and CONFIG_SHMEM=n. In this case ipc/shm is backed by ramfs which doesn't provide f_op->get_unmapped_area for configurations with MMU. The solution is to provide dummy f_op->get_unmapped_area for ramfs when CONFIG_MMU=y, which just call current->mm->get_unmapped_area(). Fixes: c01d5b3007 ("shmem: get_unmapped_area align huge page") Link: http://lkml.kernel.org/r/20160912102704.140442-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Tony Battersby <tonyb@cybernetics.com> Tested-by: Tony Battersby <tonyb@cybernetics.com> Cc: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> [4.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2016-09-19 15:36:17 -07:00
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file-mmu.c	ipc/shm: fix crash if CONFIG_SHMEM is not set	2016-09-19 15:36:17 -07:00
file-nommu.c	tmpfs/ramfs: fix VM_MAYSHARE mappings for NOMMU	2016-05-20 17:58:30 -07:00
inode.c	mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros	2016-04-04 10:41:08 -07:00
internal.h	fs/ramfs: move ramfs_aops to inode.c	2014-01-23 16:36:58 -08:00
Makefile	Remove valueless definition of hard-selected RAMFS option	2007-10-17 08:42:56 -07:00