From 029cc8c46c603ad86ae1ec924474c19775f9e0e8 Mon Sep 17 00:00:00 2001 From: Jim Somerville Date: Wed, 20 Feb 2013 13:13:33 +1100 Subject: [PATCH] inotify: remove broken mask checks causing unmount to be EINVAL Running the command: inotifywait -e unmount /mnt/disk immediately aborts with a -EINVAL return code. This is however a valid parameter. This abort occurs only if unmount is the sole event parameter. If other event parameters are supplied, then the unmount event wait will work. The problem was introduced by commit 44b350fc23e ("inotify: Fix mask checks"). In that commit, it states: The mask checks in inotify_update_existing_watch() and inotify_new_watch() are useless because inotify_arg_to_mask() sets FS_IN_IGNORED and FS_EVENT_ON_CHILD bits anyway. But instead of removing the useless checks, it did this: mask = inotify_arg_to_mask(arg); - if (unlikely(!mask)) + if (unlikely(!(mask & IN_ALL_EVENTS))) return -EINVAL; The problem is that IN_ALL_EVENTS doesn't include IN_UNMOUNT, and other parts of the code keep IN_UNMOUNT separate from IN_ALL_EVENTS. So the check should be: if (unlikely(!(mask & (IN_ALL_EVENTS | IN_UNMOUNT)))) But inotify_arg_to_mask(arg) always sets the IN_UNMOUNT bit in the mask anyway, so the check is always going to pass and thus should simply be removed. Also note that inotify_arg_to_mask completely controls what mask bits get set from arg, there's no way for invalid bits to get enabled there. Lets fix it by simply removing the useless broken checks. Signed-off-by: Jim Somerville Signed-off-by: Paul Gortmaker Cc: Jerome Marchand Cc: John McCutchan Cc: Robert Love Cc: Eric Paris Cc: [2.6.37+] Signed-off-by: Andrew Morton --- fs/notify/inotify/inotify_user.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 228a2c2ad8d7..07f7a92fe88e 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -576,8 +576,6 @@ static int inotify_update_existing_watch(struct fsnotify_group *group, /* don't allow invalid bits: we don't want flags set */ mask = inotify_arg_to_mask(arg); - if (unlikely(!(mask & IN_ALL_EVENTS))) - return -EINVAL; fsn_mark = fsnotify_find_inode_mark(group, inode); if (!fsn_mark) @@ -629,8 +627,6 @@ static int inotify_new_watch(struct fsnotify_group *group, /* don't allow invalid bits: we don't want flags set */ mask = inotify_arg_to_mask(arg); - if (unlikely(!(mask & IN_ALL_EVENTS))) - return -EINVAL; tmp_i_mark = kmem_cache_alloc(inotify_inode_mark_cachep, GFP_KERNEL); if (unlikely(!tmp_i_mark)) -- 2.39.5