io_uring: avoid pointless cred reference count bump

req->creds and ctx->sq_creds already hold reference counts that are
stable during the operations.

Link: https://lore.kernel.org/r/20241125-work-cred-v2-22-68b9d38bb5b2@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 3e408c8442d49dc1579387fe38590039fb2c4b73..06ff41484e29c6e7d8779bd7ff8317ebae003a8d 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1728,7 +1728,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
                return -EBADF;
 
        if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred()))
-               creds = override_creds(get_new_cred(req->creds));
+               creds = override_creds(req->creds);
 
        if (!def->audit_skip)
                audit_uring_entry(req->opcode);
@@ -1739,7 +1739,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
                audit_uring_exit(!ret, ret);
 
        if (creds)
-               put_cred(revert_creds(creds));
+               revert_creds(creds);
 
        if (ret == IOU_OK) {
                if (issue_flags & IO_URING_F_COMPLETE_DEFER)

diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c
index 1ca96347433695de1eb0e3bec7c6da4299e9ceb0..6df5e649c413e39e36db6cde2a8c6745e533bea9 100644 (file)
--- a/io_uring/sqpoll.c
+++ b/io_uring/sqpoll.c
@@ -174,7 +174,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
                const struct cred *creds = NULL;
 
                if (ctx->sq_creds != current_cred())
-                       creds = override_creds(get_new_cred(ctx->sq_creds));
+                       creds = override_creds(ctx->sq_creds);
 
                mutex_lock(&ctx->uring_lock);
                if (!wq_list_empty(&ctx->iopoll_list))
@@ -192,7 +192,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
                if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
                        wake_up(&ctx->sqo_sq_wait);
                if (creds)
-                       put_cred(revert_creds(creds));
+                       revert_creds(creds);
        }
 
        return ret;