From 03582094da1ea7ce978cec58008c81f7458ee8dd Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Tue, 18 Jun 2024 12:04:39 +0200 Subject: [PATCH] contrib/vhost-user-blk: fix bind() using the right size of the address MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit On macOS passing `-s /tmp/vhost.socket` parameter to the vhost-user-blk application, the bind was done on `/tmp/vhost.socke` pathname, missing the last character. This sounds like one of the portability problems described in the unix(7) manpage: Pathname sockets When binding a socket to a pathname, a few rules should be observed for maximum portability and ease of coding: • The pathname in sun_path should be null-terminated. • The length of the pathname, including the terminating null byte, should not exceed the size of sun_path. • The addrlen argument that describes the enclosing sockaddr_un structure should have a value of at least: offsetof(struct sockaddr_un, sun_path) + strlen(addr.sun_path)+1 or, more simply, addrlen can be specified as sizeof(struct sockaddr_un). So let's follow the last advice and simplify the code as well. Reviewed-by: Philippe Mathieu-Daudé Tested-by: Philippe Mathieu-Daudé Acked-by: Stefan Hajnoczi Reviewed-by: David Hildenbrand Signed-off-by: Stefano Garzarella Message-Id: <20240618100440.145664-1-sgarzare@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- contrib/vhost-user-blk/vhost-user-blk.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/contrib/vhost-user-blk/vhost-user-blk.c b/contrib/vhost-user-blk/vhost-user-blk.c index 89e5f11a64..a8ab9269a2 100644 --- a/contrib/vhost-user-blk/vhost-user-blk.c +++ b/contrib/vhost-user-blk/vhost-user-blk.c @@ -469,7 +469,6 @@ static int unix_sock_new(char *unix_fn) { int sock; struct sockaddr_un un; - size_t len; assert(unix_fn); @@ -481,10 +480,9 @@ static int unix_sock_new(char *unix_fn) un.sun_family = AF_UNIX; (void)snprintf(un.sun_path, sizeof(un.sun_path), "%s", unix_fn); - len = sizeof(un.sun_family) + strlen(un.sun_path); (void)unlink(unix_fn); - if (bind(sock, (struct sockaddr *)&un, len) < 0) { + if (bind(sock, (struct sockaddr *)&un, sizeof(un)) < 0) { perror("bind"); goto fail; } -- 2.39.5