From: Miklos Szeredi <mszeredi@suse.cz>
Use FS_SAFE for "fuse" fs type, but not for "fuseblk".
FUSE was designed from the beginning to be safe for unprivileged users.  This

has also been verified in practice over many years.  In addition unprivileged

mounts require the parent mount to be owned by the user, which is more strict

than the current userspace policy.
This will enable future installations to remove the suid-root fusermount

utility.
Don't require the "user_id=" and "group_id=" options for unprivileged mounts,

but if they are present, verify them for sanity.
Disallow the "allow_other" option for unprivileged mounts.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

---
Index: linux/fs/fuse/inode.c

===================================================================

--- linux.orig/fs/fuse/inode.c	2007-04-26 13:07:11.000000000 +0200

+++ linux/fs/fuse/inode.c	2007-04-26 13:07:33.000000000 +0200

@@ -311,6 +311,19 @@ static int parse_fuse_opt(char *opt, str

 	d->max_read = ~0;

 	d->blksize = 512;
+	/*

+	 * For unprivileged mounts use current uid/gid.  Still allow

+	 * "user_id" and "group_id" options for compatibility, but

+	 * only if they match these values.

+	 */

+	if (!capable(CAP_SYS_ADMIN)) {

+		d->user_id = current->uid;

+		d->user_id_present = 1;

+		d->group_id = current->gid;

+		d->group_id_present = 1;

+

+	}

+

 	while ((p = strsep(&opt, ",")) != NULL) {

 		int token;

 		int value;

@@ -339,6 +352,8 @@ static int parse_fuse_opt(char *opt, str

 		case OPT_USER_ID:

 			if (match_int(&args[0], &value))

 				return 0;

+			if (d->user_id_present && d->user_id != value)

+				return 0;

 			d->user_id = value;

 			d->user_id_present = 1;

 			break;

@@ -346,6 +361,8 @@ static int parse_fuse_opt(char *opt, str

 		case OPT_GROUP_ID:

 			if (match_int(&args[0], &value))

 				return 0;

+			if (d->group_id_present && d->group_id != value)

+				return 0;

 			d-&gt...
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