[PATCH v2] fsnotify: Open handle with O_PATH

[Cyrill Gorcunov]

Otherwise if the mark is set up on link we end
with -ELOOP error trying to open it. Thus, use
O_PATH pointing the kernel that we're not going
to read/write this descriptor.

Repored-by: Andrew Vagin <avagin at parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov at openvz.org>
Acked-by: Andrew Vagin <avagin at parallels.com>
---

Add definition of O_PATH.

 fsnotify.c      | 2 +-
 include/fcntl.h | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/fsnotify.c b/fsnotify.c
index 3f5ef6280bc8..476fb2620bd0 100644
--- a/fsnotify.c
+++ b/fsnotify.c
@@ -114,7 +114,7 @@ static int open_handle(unsigned int s_dev, unsigned long i_ino,
 		goto out;
 	}
 
-	fd = sys_open_by_handle_at(mntfd, (void *)&handle, 0);
+	fd = sys_open_by_handle_at(mntfd, (void *)&handle, O_PATH);
 	if (fd < 0)
 		pr_perror("Can't open file handle for 0x%08x:0x%016lx",
 				s_dev, i_ino);
diff --git a/include/fcntl.h b/include/fcntl.h
index 65ba2bfe2632..6f85c5ee6923 100644
--- a/include/fcntl.h
+++ b/include/fcntl.h
@@ -29,4 +29,8 @@ struct f_owner_ex {
 # define F_GETPIPE_SZ	(F_LINUX_SPECIFIC_BASE + 8)
 #endif
 
+#ifndef O_PATH
+# define O_PATH		010000000
+#endif
+
 #endif /* __CR_ASM_GENERIC_FCNTL_H__ */
-- 
1.8.3.1


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