Commit c7094274 authored Feb 13, 2025 by Maciej Szulik Committed by Jim Harris Apr 14, 2025

sock: fix wrap around for zcopy request



Kernel can use the whole range of uint32 to report a completion index.
We can miss one by wrapping from UINT32_MAX to 1.

Fixes issue #3600.

Signed-off-by: Maciej Szulik <maciej.szulik@intel.com>
Reported-by: Ariel Marcovitch
Change-Id: Ide1bb31ec2d59059adb7564d0b7699a781942301
Reviewed-on: https://review.spdk.io/c/spdk/spdk/+/25650


Reviewed-by: Jacek Kalwas <jacek.kalwas@nutanix.com>
Community-CI: Mellanox Build Bot
Reviewed-by: Aleksey Marchuk <alexeymar@nvidia.com>
Reviewed-by: GangCao <gang.cao@intel.com>
Reviewed-by: Jim Harris <jim.harris@nvidia.com>
Tested-by: SPDK Automated Test System <spdkbot@gmail.com>
Reviewed-by: Ben Walker <ben@nvidia.com>

parent dca18c42

module/sock/posix/posix.c

+1 −7

Original line number	Diff line number	Diff line
		@@ -1401,14 +1401,8 @@ _sock_flush(struct spdk_sock *sock)
		sent = rc;

		if (is_zcopy) {
		/* Handling overflow case, because we use psock->sendmsg_idx - 1 for the
		* req->internal.offset, so sendmsg_idx should not be zero */
		if (spdk_unlikely(psock->sendmsg_idx == UINT32_MAX)) {
		psock->sendmsg_idx = 1;
		} else {
		psock->sendmsg_idx++;
		}
		}

		/* Consume the requests that were actually written */
		req = TAILQ_FIRST(&sock->queued_reqs);

module/sock/uring/uring.c

+1 −7

Original line number	Diff line number	Diff line
		@@ -1091,14 +1091,8 @@ sock_complete_write_reqs(struct spdk_sock *_sock, ssize_t rc, bool is_zcopy)
		int retval;

		if (is_zcopy) {
		/* Handling overflow case, because we use psock->sendmsg_idx - 1 for the
		* req->internal.offset, so sendmsg_idx should not be zero */
		if (spdk_unlikely(sock->sendmsg_idx == UINT32_MAX)) {
		sock->sendmsg_idx = 1;
		} else {
		sock->sendmsg_idx++;
		}
		}

		/* Consume the requests that were actually written */
		req = TAILQ_FIRST(&_sock->queued_reqs);