Commit 10eec60c authored Jul 27, 2016 by Scott Bauer Committed by Linus Torvalds Jul 28, 2016

vfs: ioctl: prevent double-fetch in dedupe ioctl



This prevents a double-fetch from user space that can lead to to an
undersized allocation and heap overflow.

Fixes: 54dbc151 ("vfs: hoist the btrfs deduplication ioctl to the vfs")
Signed-off-by: Scott Bauer <sbauer@plzdonthack.me>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 884316de

fs/ioctl.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -590,6 +590,7 @@ static long ioctl_file_dedupe_range(struct file file, void __user arg)
		goto out;
		}

		same->dest_count = count;
		ret = vfs_dedupe_file_range(file, same);
		if (ret)
		goto out;