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| author | Amir Goldstein <amir73il@gmail.com> | 2023-11-22 14:27:01 +0200 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2023-11-24 09:22:27 +0100 |
| commit | 2a33e2ddc6ebf9b5468091aded8a38f57de9a580 (patch) | |
| tree | 115438e435c36d6e345343541c5f4bafe7ef55b7 /fs/splice.c | |
| parent | ca7ab482401cf0a7497dad05f4918dc64115538b (diff) | |
| download | linux-2a33e2ddc6ebf9b5468091aded8a38f57de9a580.tar.gz linux-2a33e2ddc6ebf9b5468091aded8a38f57de9a580.tar.bz2 linux-2a33e2ddc6ebf9b5468091aded8a38f57de9a580.zip | |
splice: remove permission hook from do_splice_direct()
All callers of do_splice_direct() have a call to rw_verify_area() for
the entire range that is being copied, e.g. by vfs_copy_file_range() or
do_sendfile() before calling do_splice_direct().
The rw_verify_area() check inside do_splice_direct() is redundant and
is called after sb_start_write(), so it is not "start-write-safe".
Remove this redundant check.
This is needed for fanotify "pre content" events.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20231122122715.2561213-3-amir73il@gmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'fs/splice.c')
| -rw-r--r-- | fs/splice.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/fs/splice.c b/fs/splice.c index d983d375ff11..6e917db6f49a 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1166,6 +1166,7 @@ static void direct_file_splice_eof(struct splice_desc *sd) * (splice in + splice out, as compared to just sendfile()). So this helper * can splice directly through a process-private pipe. * + * Callers already called rw_verify_area() on the entire range. */ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, loff_t *opos, size_t len, unsigned int flags) @@ -1187,10 +1188,6 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, if (unlikely(out->f_flags & O_APPEND)) return -EINVAL; - ret = rw_verify_area(WRITE, out, opos, len); - if (unlikely(ret < 0)) - return ret; - ret = splice_direct_to_actor(in, &sd, direct_splice_actor); if (ret > 0) *ppos = sd.pos; |