From: Zev Weiss <zev@bewilderbeest.net>
Date: Sat, 14 Apr 2018 06:16:58 +0000 (-0500)
Subject: fs: avoid fdput() after failed fdget() in vfs_dedupe_file_range()
X-Git-Tag: v4.19~946^2~11
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=22762711479959754e005f5bb8e6abc37bf9e0ba;p=platform%2Fkernel%2Flinux-rpi3.git

fs: avoid fdput() after failed fdget() in vfs_dedupe_file_range()

It's a fairly inconsequential bug, since fdput() won't actually try to
fput() the file due to fd.flags (and thus FDPUT_FPUT) being zero in
the failure case, but most other vfs code takes steps to avoid this.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/read_write.c b/fs/read_write.c
index c4eabbf..e83bd97 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -2023,7 +2023,7 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
 		ret = mnt_want_write_file(dst_file);
 		if (ret) {
 			info->status = ret;
-			goto next_loop;
+			goto next_fdput;
 		}
 
 		dst_off = info->dest_offset;
@@ -2058,9 +2058,9 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
 
 next_file:
 		mnt_drop_write_file(dst_file);
-next_loop:
+next_fdput:
 		fdput(dst_fd);
-
+next_loop:
 		if (fatal_signal_pending(current))
 			goto out;
 	}