commit 87a818e80dd7b59d2ee3f9b1cdffc82d7c5c1b4c
from: Omar Polo <op@omarpolo.com>
date: Tue Dec 14 22:32:36 2021 UTC

ensure we don't call openat(2) with "" as path

commit - cf758c3329364c1516e2b78c573d6901843bc670
commit + 87a818e80dd7b59d2ee3f9b1cdffc82d7c5c1b4c
blob - 5acf852dec04af7440d6eb40c4a8f159f7f7a8b4
blob + 5519c0909c9c72e32d8fc7455e1aa62bc156dfe0
--- client.c
+++ client.c
@@ -1053,6 +1053,7 @@ topen(struct np_msg_header *hdr, const uint8_t *data, 
 	struct fid	*f;
 	uint32_t	 fid;
 	uint8_t		 mode;
+	const char	*path;
 
 	/* fid[4] mode[1] */
 	if (!NPREAD32("fid", &fid, &data, &len) ||
@@ -1083,7 +1084,11 @@ topen(struct np_msg_header *hdr, const uint8_t *data, 
 		return;
 	}
 
-	if ((f->fd = openat(f->qid->fd, f->qid->fpath, f->iomode)) == -1) {
+	path = f->qid->fpath;
+	if (*path == '\0')
+		path = ".";
+
+	if ((f->fd = openat(f->qid->fd, path, f->iomode)) == -1) {
 		np_error(hdr->tag, strerror(errno));
 		return;
 	}