+ readahead-fix-null-filp-dereference.patch added to -mm tree

+ readahead-fix-null-filp-dereference.patch added to -mm tree

[akpm]

The patch titled
     readahead: fix NULL filp dereference
has been added to the -mm tree.  Its filename is
     readahead-fix-null-filp-dereference.patch

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out what to do about this

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: readahead: fix NULL filp dereference
From: Wu Fengguang <fengguang.wu@intel.com>

btrfs relocate_file_extent_cluster() calls us with NULL filp:

  [ 4005.426805] BUG: unable to handle kernel NULL pointer dereference at 00000021
  [ 4005.426818] IP: [<c109a130>] page_cache_sync_readahead+0x18/0x3e

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Yan Zheng <yanzheng@21cn.com>
Reported-by: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/readahead.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN mm/readahead.c~readahead-fix-null-filp-dereference mm/readahead.c
--- a/mm/readahead.c~readahead-fix-null-filp-dereference
+++ a/mm/readahead.c
@@ -503,7 +503,7 @@ void page_cache_sync_readahead(struct ad
 		return;
 
 	/* be dumb */
-	if (filp->f_mode & FMODE_RANDOM) {
+	if (filp && (filp->f_mode & FMODE_RANDOM)) {
 		force_page_cache_readahead(mapping, filp, offset, req_size);
 		return;
 	}
_

Patches currently in -mm which might be from fengguang.wu@intel.com are

linux-next.patch
include-linux-fsh-complete-hexification-of-fmode_-constants.patch
readahead-fix-null-filp-dereference.patch
vfs-o_-bit-numbers-uniqueness-check.patch
vfs-o_-bit-numbers-uniqueness-check-update.patch
vfs-o_-bit-numbers-uniqueness-check-fix.patch
vfs-o_-bit-numbers-uniqueness-check-fix-2.patch
vfs-introduce-fmode_neg_offset-for-allowing-negative-f_pos.patch
vfs-add-super-operation-writeback_inodes.patch