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| author | Miklos Szeredi <mszeredi@redhat.com> | 2020-12-14 15:26:13 +0100 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2020-12-14 15:26:13 +0100 |
| commit | 3078d85c9a1099405a0463c4d112ba97ee5bd217 (patch) | |
| tree | c616c7bb447c3579c4af62f48563cace12beb73a /fs/remap_range.c | |
| parent | 7c03e2cda4a584cadc398e8f6641ca9988a39d52 (diff) | |
| download | lwn-3078d85c9a1099405a0463c4d112ba97ee5bd217.tar.gz lwn-3078d85c9a1099405a0463c4d112ba97ee5bd217.zip | |
vfs: verify source area in vfs_dedupe_file_range_one()
Call remap_verify_area() on the source file as well as the destination.
When called from vfs_dedupe_file_range() the check as already been
performed, but not so if called from layered fs (overlayfs, etc...)
Could ommit the redundant check in vfs_dedupe_file_range(), but leave for
now to get error early (for fear of breaking backward compatibility).
This call shouldn't be performance sensitive.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/remap_range.c')
| -rw-r--r-- | fs/remap_range.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/fs/remap_range.c b/fs/remap_range.c index e6099beefa97..77dba3a49e65 100644 --- a/fs/remap_range.c +++ b/fs/remap_range.c @@ -456,8 +456,16 @@ loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, if (ret) return ret; + /* + * This is redundant if called from vfs_dedupe_file_range(), but other + * callers need it and it's not performance sesitive... + */ + ret = remap_verify_area(src_file, src_pos, len, false); + if (ret) + goto out_drop_write; + ret = remap_verify_area(dst_file, dst_pos, len, true); - if (ret < 0) + if (ret) goto out_drop_write; ret = -EPERM; |