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From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        linux-fsdevel@vger.kernel.org
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        Christian Brauner <christian.brauner@ubuntu.com>,
        Christoph Hellwig <hch@lst.de>
Subject: [PATCH v2 23/39] fcntl: handle idmapped mounts
Date:   Sun, 15 Nov 2020 11:37:02 +0100
Message-Id: <20201115103718.298186-24-christian.brauner@ubuntu.com>
In-Reply-To: <20201115103718.298186-1-christian.brauner@ubuntu.com>
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Enable the setfl() helper to handle idmapped mounts by passing down the
mount's user namespace.

Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
---
 fs/fcntl.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/fcntl.c b/fs/fcntl.c
index df091d435603..ed330fa91438 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -25,6 +25,7 @@
 #include <linux/user_namespace.h>
 #include <linux/memfd.h>
 #include <linux/compat.h>
+#include <linux/mount.h>
 
 #include <linux/poll.h>
 #include <asm/siginfo.h>
@@ -46,7 +47,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 
 	/* O_NOATIME can only be set by the owner or superuser */
 	if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
-		if (!inode_owner_or_capable(&init_user_ns, inode))
+		if (!inode_owner_or_capable(mnt_user_ns(filp->f_path.mnt), inode))
 			return -EPERM;
 
 	/* required for strict SunOS emulation */
-- 
2.29.2