commit d8dd8bd77f67af6bb2047bda0fa010ff80d36be5
from: Omar Polo <op@omarpolo.com>
date: Sun Jan 02 10:42:18 2022 UTC

tread: read at most the requested size

spotted by cage, thanks!

commit - 98576296154a0e6fe5c6fc4b3b517cfb9c3e4402
commit + d8dd8bd77f67af6bb2047bda0fa010ff80d36be5
blob - 677d0175769dee1f73404b966c7291e325e408aa
blob + 8802f85f95e5518dd7736cf73df9e190da4c0e8b
--- client.c
+++ client.c
@@ -1371,6 +1371,7 @@ tread(struct np_msg_header *hdr, const uint8_t *data, 
 {
 	struct fid	*f;
 	ssize_t		 r;
+	size_t		 howmuch;
 	uint64_t	 off;
 	uint32_t	 fid, count;
 	char		 buf[2048];
@@ -1397,7 +1398,8 @@ tread(struct np_msg_header *hdr, const uint8_t *data, 
 
 	if (f->d == NULL) {
 		/* read a file */
-		r = pread(f->fd, buf, sizeof(buf), (off_t)off);
+		howmuch = MIN(sizeof(buf), count);
+		r = pread(f->fd, buf, howmuch, (off_t)off);
 		if (r == -1)
 			np_errno(hdr->tag);
 		else