releases/3.4.51/inotify-invalid-mask-should-return-a-error-number-but-not-set-it.patch

   1 From 04df32fa10ab9a6f0643db2949d42efc966bc844 Mon Sep 17 00:00:00 2001
   2 From: Zhao Hongjiang <zhaohongjiang@huawei.com>
   3 Date: Tue, 30 Apr 2013 15:26:46 -0700
   4 Subject: inotify: invalid mask should return a error number but not set it
   5
   6 From: Zhao Hongjiang <zhaohongjiang@huawei.com>
   7
   8 commit 04df32fa10ab9a6f0643db2949d42efc966bc844 upstream.
   9
  10 When we run the crackerjack testsuite, the inotify_add_watch test is
  11 stalled.
  12
  13 This is caused by the invalid mask 0 - the task is waiting for the event
  14 but it never comes.  inotify_add_watch() should return -EINVAL as it did
  15 before commit 676a0675cf92 ("inotify: remove broken mask checks causing
  16 unmount to be EINVAL").  That commit removes the invalid mask check, but
  17 that check is needed.
  18
  19 Check the mask's ALL_INOTIFY_BITS before the inotify_arg_to_mask() call.
  20 If none are set, just return -EINVAL.
  21
  22 Because IN_UNMOUNT is in ALL_INOTIFY_BITS, this change will not trigger
  23 the problem that above commit fixed.
  24
  25 [akpm@linux-foundation.org: fix build]
  26 Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com>
  27 Acked-by: Jim Somerville <Jim.Somerville@windriver.com>
  28 Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
  29 Cc: Jerome Marchand <jmarchan@redhat.com>
  30 Cc: Eric Paris <eparis@parisplace.org>
  31 Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  32 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  33 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  34
  35
  36 ---
  37  fs/notify/inotify/inotify_user.c |    6 ++++--
  38  1 file changed, 4 insertions(+), 2 deletions(-)
  39
  40 --- a/fs/notify/inotify/inotify_user.c
  41 +++ b/fs/notify/inotify/inotify_user.c
  42 @@ -577,7 +577,6 @@ static int inotify_update_existing_watch
  43         int add = (arg & IN_MASK_ADD);
  44         int ret;
  45
  46 -       /* don't allow invalid bits: we don't want flags set */
  47         mask = inotify_arg_to_mask(arg);
  48
  49         fsn_mark = fsnotify_find_inode_mark(group, inode);
  50 @@ -628,7 +627,6 @@ static int inotify_new_watch(struct fsno
  51         struct idr *idr = &group->inotify_data.idr;
  52         spinlock_t *idr_lock = &group->inotify_data.idr_lock;
  53
  54 -       /* don't allow invalid bits: we don't want flags set */
  55         mask = inotify_arg_to_mask(arg);
  56
  57         tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL);
  58 @@ -757,6 +755,10 @@ SYSCALL_DEFINE3(inotify_add_watch, int,
  59         int ret, fput_needed;
  60         unsigned flags = 0;
  61
  62 +       /* don't allow invalid bits: we don't want flags set */
  63 +       if (unlikely(!(mask & ALL_INOTIFY_BITS)))
  64 +               return -EINVAL;
  65 +
  66         filp = fget_light(fd, &fput_needed);
  67         if (unlikely(!filp))
  68                 return -EBADF;