[PATCH 05/16] backing-file: use credential guards for splice read

From: Christian Brauner
Date: Mon Nov 03 2025 - 06:31:12 EST


Use credential guards for scoped credential override with automatic
restoration on scope exit.

Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
---
fs/backing-file.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/backing-file.c b/fs/backing-file.c
index 9bea737d5bef..8ebc62f49bad 100644
--- a/fs/backing-file.c
+++ b/fs/backing-file.c
@@ -283,15 +283,13 @@ ssize_t backing_file_splice_read(struct file *in, struct kiocb *iocb,
unsigned int flags,
struct backing_file_ctx *ctx)
{
- const struct cred *old_cred;
ssize_t ret;

if (WARN_ON_ONCE(!(in->f_mode & FMODE_BACKING)))
return -EIO;

- old_cred = override_creds(ctx->cred);
- ret = vfs_splice_read(in, &iocb->ki_pos, pipe, len, flags);
- revert_creds(old_cred);
+ scoped_with_creds(ctx->cred)
+ ret = vfs_splice_read(in, &iocb->ki_pos, pipe, len, flags);

if (ctx->accessed)
ctx->accessed(iocb->ki_filp);

--
2.47.3