From 92b66d2cdd7a4f6f6aa31be5f16a3f0c88902690 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <mszeredi@redhat.com>
Date: Fri, 6 Jul 2018 23:57:02 +0200
Subject: [PATCH] vfs: limit size of dedupe
Git-commit: 92b66d2cdd7a4f6f6aa31be5f16a3f0c88902690
Patch-mainline: v4.19-rc1
References: bsc#1132397, bsc#1132219
Suggested-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Acked-by: Anthony Iliopoulos <ailiopoulos@suse.com>
---
fs/read_write.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/read_write.c b/fs/read_write.c
index 153f8f690490..f43bb12b4759 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -2003,6 +2003,9 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
if (off + len > i_size_read(src))
return -EINVAL;
+ /* Arbitrary 1G limit on a single dedupe request, can be raised. */
+ len = min_t(u64, len, 1 << 30);
+
/* pre-format output fields to sane values */
for (i = 0; i < count; i++) {
same->info[i].bytes_deduped = 0ULL;
--
2.16.4