linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Amir Goldstein <amir73il@gmail.com>
To: Jan Kara <jack@suse.cz>
Cc: linux-fsdevel@vger.kernel.org
Subject: [PATCH v5 06/22] fanotify: prepare for implicit event flags in mark mask
Date: Thu, 16 Jul 2020 11:42:14 +0300	[thread overview]
Message-ID: <20200716084230.30611-7-amir73il@gmail.com> (raw)
In-Reply-To: <20200716084230.30611-1-amir73il@gmail.com>

So far, all flags that can be set in an fanotify mark mask can be set
explicitly by a call to fanotify_mark(2).

Prepare for defining implicit event flags that cannot be set by user with
fanotify_mark(2), similar to how inotify/dnotify implicitly set the
FS_EVENT_ON_CHILD flag.

Implicit event flags cannot be removed by user and mark gets destroyed
when only implicit event flags remain in the mask.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 fs/notify/fanotify/fanotify_user.c | 40 ++++++++++++++++++------------
 1 file changed, 24 insertions(+), 16 deletions(-)

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 6d30beb320f3..ab974cd234f7 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -656,12 +656,13 @@ static int fanotify_find_path(int dfd, const char __user *filename,
 }
 
 static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
-					    __u32 mask,
-					    unsigned int flags,
-					    int *destroy)
+					    __u32 mask, unsigned int flags,
+					    __u32 umask, int *destroy)
 {
 	__u32 oldmask = 0;
 
+	/* umask bits cannot be removed by user */
+	mask &= ~umask;
 	spin_lock(&fsn_mark->lock);
 	if (!(flags & FAN_MARK_IGNORED_MASK)) {
 		oldmask = fsn_mark->mask;
@@ -669,7 +670,13 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
 	} else {
 		fsn_mark->ignored_mask &= ~mask;
 	}
-	*destroy = !(fsn_mark->mask | fsn_mark->ignored_mask);
+	/*
+	 * We need to keep the mark around even if remaining mask cannot
+	 * result in any events (e.g. mask == FAN_ONDIR) to support incremenal
+	 * changes to the mask.
+	 * Destroy mark when only umask bits remain.
+	 */
+	*destroy = !((fsn_mark->mask | fsn_mark->ignored_mask) & ~umask);
 	spin_unlock(&fsn_mark->lock);
 
 	return mask & oldmask;
@@ -677,7 +684,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
 
 static int fanotify_remove_mark(struct fsnotify_group *group,
 				fsnotify_connp_t *connp, __u32 mask,
-				unsigned int flags)
+				unsigned int flags, __u32 umask)
 {
 	struct fsnotify_mark *fsn_mark = NULL;
 	__u32 removed;
@@ -691,7 +698,7 @@ static int fanotify_remove_mark(struct fsnotify_group *group,
 	}
 
 	removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags,
-						 &destroy_mark);
+						 umask, &destroy_mark);
 	if (removed & fsnotify_conn_mask(fsn_mark->connector))
 		fsnotify_recalc_mask(fsn_mark->connector);
 	if (destroy_mark)
@@ -707,25 +714,26 @@ static int fanotify_remove_mark(struct fsnotify_group *group,
 
 static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
 					 struct vfsmount *mnt, __u32 mask,
-					 unsigned int flags)
+					 unsigned int flags, __u32 umask)
 {
 	return fanotify_remove_mark(group, &real_mount(mnt)->mnt_fsnotify_marks,
-				    mask, flags);
+				    mask, flags, umask);
 }
 
 static int fanotify_remove_sb_mark(struct fsnotify_group *group,
-				      struct super_block *sb, __u32 mask,
-				      unsigned int flags)
+				   struct super_block *sb, __u32 mask,
+				   unsigned int flags, __u32 umask)
 {
-	return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask, flags);
+	return fanotify_remove_mark(group, &sb->s_fsnotify_marks, mask,
+				    flags, umask);
 }
 
 static int fanotify_remove_inode_mark(struct fsnotify_group *group,
 				      struct inode *inode, __u32 mask,
-				      unsigned int flags)
+				      unsigned int flags, __u32 umask)
 {
 	return fanotify_remove_mark(group, &inode->i_fsnotify_marks, mask,
-				    flags);
+				    flags, umask);
 }
 
 static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
@@ -1175,13 +1183,13 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	case FAN_MARK_REMOVE:
 		if (mark_type == FAN_MARK_MOUNT)
 			ret = fanotify_remove_vfsmount_mark(group, mnt, mask,
-							    flags);
+							    flags, 0);
 		else if (mark_type == FAN_MARK_FILESYSTEM)
 			ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask,
-						      flags);
+						      flags, 0);
 		else
 			ret = fanotify_remove_inode_mark(group, inode, mask,
-							 flags);
+							 flags, 0);
 		break;
 	default:
 		ret = -EINVAL;
-- 
2.17.1


  parent reply	other threads:[~2020-07-16  8:42 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-16  8:42 [PATCH v5 00/22] fanotify events with name info Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 01/22] fanotify: generalize the handling of extra event flags Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 02/22] fanotify: generalize merge logic of events on dir Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 03/22] fanotify: distinguish between fid encode error and null fid Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 04/22] fanotify: generalize test for FAN_REPORT_FID Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 05/22] fanotify: mask out special event flags from ignored mask Amir Goldstein
2020-07-16  8:42 ` Amir Goldstein [this message]
2020-07-16  8:42 ` [PATCH v5 07/22] fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 08/22] fsnotify: add object type "child" to object type iterator Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 09/22] fanotify: use struct fanotify_info to parcel the variable size buffer Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 10/22] fanotify: no external fh buffer in fanotify_name_event Amir Goldstein
2020-07-16 12:44   ` Jan Kara
2020-07-16 13:30     ` Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 11/22] dnotify: report both events on parent and child with single callback Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 12/22] inotify: " Amir Goldstein
2020-07-16 12:52   ` Jan Kara
2020-07-16 14:25     ` Amir Goldstein
2020-07-16 15:17       ` Jan Kara
2020-07-16  8:42 ` [PATCH v5 13/22] fanotify: " Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 14/22] fsnotify: send event to " Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 15/22] fsnotify: send event with parent/name info to sb/mount/non-dir marks Amir Goldstein
2020-07-16 17:01   ` Jan Kara
2020-07-16 17:20     ` Amir Goldstein
2020-07-16 17:57       ` Jan Kara
2020-07-16 18:42         ` Amir Goldstein
2020-07-16 22:34           ` Jan Kara
2020-07-17  3:49             ` Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 16/22] fsnotify: remove check that source dentry is positive Amir Goldstein
2020-07-16 13:13   ` Jan Kara
2020-07-16 13:29     ` Jan Kara
2020-07-16 13:54       ` Amir Goldstein
2020-07-16 14:06         ` Jan Kara
2020-07-16  8:42 ` [PATCH v5 17/22] fsnotify: send MOVE_SELF event with parent/name info Amir Goldstein
2020-07-16 13:45   ` Jan Kara
2020-07-16 13:59     ` Amir Goldstein
2020-07-16 14:10       ` Amir Goldstein
2020-07-16 15:57         ` Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 18/22] fanotify: add basic support for FAN_REPORT_DIR_FID Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 19/22] fanotify: report events with parent dir fid to sb/mount/non-dir marks Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 20/22] fanotify: add support for FAN_REPORT_NAME Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 21/22] fanotify: report parent fid + name + child fid Amir Goldstein
2020-07-16 15:59   ` Jan Kara
2020-07-16 16:08     ` Amir Goldstein
2020-07-16  8:42 ` [PATCH v5 22/22] fanotify: report parent fid " Amir Goldstein
2020-07-16 17:13 ` [PATCH v5 00/22] fanotify events with name info Jan Kara

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200716084230.30611-7-amir73il@gmail.com \
    --to=amir73il@gmail.com \
    --cc=jack@suse.cz \
    --cc=linux-fsdevel@vger.kernel.org \
    --subject='Re: [PATCH v5 06/22] fanotify: prepare for implicit event flags in mark mask' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).