When system calls indicate an error they return -1, not some arbitrary

value < 0.  errno is only updated in this case.  Change all (most?)
callers of syscalls to follow this better, and let's see if this strictness
helps us in the future.

src/lib/libc/hash/helper.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: helper.c,v 1.17 2017/10/23 14:33:07 millert Exp $ */
+/*	$OpenBSD: helper.c,v 1.18 2019/06/28 13:32:41 deraadt Exp $ */
 
 /*
  * Copyright (c) 2000 Poul-Henning Kamp <phk@FreeBSD.org>
@@ -67,7 +67,7 @@ HASHFileChunk(const char *filename, char *buf, off_t off, off_t len)
 
 	HASHInit(&ctx);
 
-	if ((fd = open(filename, O_RDONLY)) < 0)
+	if ((fd = open(filename, O_RDONLY)) == -1)
 		return (NULL);
 	if (len == 0) {
 		if (fstat(fd, &sb) == -1) {
@@ -78,7 +78,7 @@ HASHFileChunk(const char *filename, char *buf, off_t off, off_t len)
 		}
 		len = sb.st_size;
 	}
-	if (off > 0 && lseek(fd, off, SEEK_SET) < 0) {
+	if (off > 0 && lseek(fd, off, SEEK_SET) == -1) {
 		save_errno = errno;
 		close(fd);
 		errno = save_errno;
@@ -94,7 +94,7 @@ HASHFileChunk(const char *filename, char *buf, off_t off, off_t len)
 	save_errno = errno;
 	close(fd);
 	errno = save_errno;
-	return (nr < 0 ? NULL : HASHEnd(&ctx, buf));
+	return (nr == -1 ? NULL : HASHEnd(&ctx, buf));
 }
 DEF_WEAK(HASHFileChunk);
 

src/lib/libc/stdlib/malloc.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: malloc.c,v 1.261 2019/05/23 06:43:18 otto Exp $	*/
+/*	$OpenBSD: malloc.c,v 1.262 2019/06/28 13:32:42 deraadt Exp $	*/
 /*
  * Copyright (c) 2008, 2010, 2011, 2016 Otto Moerbeek <otto@drijf.net>
  * Copyright (c) 2012 Matthew Dempsky <matthew@openbsd.org>
@@ -897,7 +897,7 @@ omalloc_make_chunks(struct dir_info *d, int bits, int listnum)
 		return NULL;
 
 	/* memory protect the page allocated in the malloc(0) case */
-	if (bits == 0 && mprotect(pp, MALLOC_PAGESIZE, PROT_NONE) < 0)
+	if (bits == 0 && mprotect(pp, MALLOC_PAGESIZE, PROT_NONE) == -1)
 		goto err;
 
 	bp = alloc_chunk_info(d, bits);

src/lib/libutil/check_expire.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: check_expire.c,v 1.12 2015/11/26 23:32:52 millert Exp $	*/
+/*	$OpenBSD: check_expire.c,v 1.13 2019/06/28 13:32:43 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved.
@@ -166,7 +166,7 @@ pwd_update(const struct passwd *pwd, const struct passwd *opwd)
 
 	pw_init();
 	tfd = pw_lock(0);
-	if (tfd < 0) {
+	if (tfd == -1) {
 		if (errno == EEXIST)
 			return("the passwd file is busy.");
 		else
@@ -174,13 +174,13 @@ pwd_update(const struct passwd *pwd, const struct passwd *opwd)
 	}
 
 	pfd = open(_PATH_MASTERPASSWD, O_RDONLY|O_CLOEXEC, 0);
-	if (pfd < 0) {
+	if (pfd == -1) {
 		pw_abort();
 		return(strerror(errno));
 	}
 
 	pw_copy(pfd, tfd, pwd, opwd);
-	if (pw_mkdb(pwd->pw_name, 0) < 0) {
+	if (pw_mkdb(pwd->pw_name, 0) == -1) {
 		pw_abort();
 		return("unable to update password database");
 	}

src/lib/libutil/getmaxpartitions.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: getmaxpartitions.c,v 1.9 2016/08/27 03:54:20 guenther Exp $	*/
+/*	$OpenBSD: getmaxpartitions.c,v 1.10 2019/06/28 13:32:43 deraadt Exp $	*/
 /*	$NetBSD: getmaxpartitions.c,v 1.1 1996/05/16 07:03:31 thorpej Exp $	*/
 
 /*-
@@ -45,7 +45,7 @@ getmaxpartitions(void)
 	mib[0] = CTL_KERN;
 	mib[1] = KERN_MAXPARTITIONS;
 	varlen = sizeof(maxpart);
-	if (sysctl(mib, 2, &maxpart, &varlen, NULL, (size_t)0) < 0)
+	if (sysctl(mib, 2, &maxpart, &varlen, NULL, (size_t)0) == -1)
 		return (-1);
 
 	return (maxpart);

src/lib/libutil/getrawpartition.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: getrawpartition.c,v 1.9 2016/08/27 03:54:20 guenther Exp $	*/
+/*	$OpenBSD: getrawpartition.c,v 1.10 2019/06/28 13:32:43 deraadt Exp $	*/
 /*	$NetBSD: getrawpartition.c,v 1.1 1996/05/16 07:03:33 thorpej Exp $	*/
 
 /*-
@@ -45,7 +45,7 @@ getrawpartition(void)
 	mib[0] = CTL_KERN;
 	mib[1] = KERN_RAWPARTITION;
 	varlen = sizeof(rawpart);
-	if (sysctl(mib, 2, &rawpart, &varlen, NULL, (size_t)0) < 0)
+	if (sysctl(mib, 2, &rawpart, &varlen, NULL, (size_t)0) == -1)
 		return (-1);
 
 	return (rawpart);

src/lib/libutil/logout.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: logout.c,v 1.9 2015/12/28 20:11:36 guenther Exp $	*/
+/*	$OpenBSD: logout.c,v 1.10 2019/06/28 13:32:43 deraadt Exp $	*/
 /*
  * Copyright (c) 1988, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -47,7 +47,7 @@ logout(const char *line)
 	int fd, rval;
 	UTMP ut;
 
-	if ((fd = open(_PATH_UTMP, O_RDWR|O_CLOEXEC)) < 0)
+	if ((fd = open(_PATH_UTMP, O_RDWR|O_CLOEXEC)) == -1)
 		return(0);
 	rval = 0;
 	while (read(fd, &ut, sizeof(UTMP)) == sizeof(UTMP)) {

src/lib/libutil/logwtmp.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: logwtmp.c,v 1.10 2016/08/30 14:44:45 guenther Exp $	*/
+/*	$OpenBSD: logwtmp.c,v 1.11 2019/06/28 13:32:43 deraadt Exp $	*/
 /*
  * Copyright (c) 1988, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -46,7 +46,7 @@ logwtmp(const char *line, const char *name, const char *host)
 	struct utmp ut;
 	int fd;
 
-	if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND|O_CLOEXEC)) < 0)
+	if ((fd = open(_PATH_WTMP, O_WRONLY|O_APPEND|O_CLOEXEC)) == -1)
 		return;
 	if (fstat(fd, &buf) == 0) {
 		(void) strncpy(ut.ut_line, line, sizeof(ut.ut_line));

src/lib/libutil/passwd.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: passwd.c,v 1.55 2018/08/10 17:03:26 deraadt Exp $	*/
+/*	$OpenBSD: passwd.c,v 1.56 2019/06/28 13:32:43 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1987, 1993, 1994, 1995
@@ -101,7 +101,7 @@ pw_lock(int retries)
 	/* Acquire the lock file.  */
 	old_mode = umask(0);
 	fd = open(pw_lck, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0600);
-	for (i = 0; i < retries && fd < 0 && errno == EEXIST; i++) {
+	for (i = 0; i < retries && fd == -1 && errno == EEXIST; i++) {
 		sleep(1);
 		fd = open(pw_lck, O_WRONLY|O_CREAT|O_EXCL|O_CLOEXEC, 0600);
 	}

src/lib/libutil/readlabel.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: readlabel.c,v 1.14 2016/08/30 14:44:45 guenther Exp $	*/
+/*	$OpenBSD: readlabel.c,v 1.15 2019/06/28 13:32:43 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1996, Jason Downs.  All rights reserved.
@@ -74,7 +74,7 @@ readlabelfs(char *device, int verbose)
 	}
 
 	/* Assuming device is of the form /dev/??p, build a raw partition. */
-	if (stat(device, &sbuf) < 0) {
+	if (stat(device, &sbuf) == -1) {
 		if (verbose)
 			warn("%s", device);
 		return (NULL);
@@ -106,12 +106,12 @@ readlabelfs(char *device, int verbose)
 
 	/* If rpath doesn't exist, change that partition back. */
 	fd = open(rpath, O_RDONLY|O_CLOEXEC);
-	if (fd < 0) {
+	if (fd == -1) {
 		if (errno == ENOENT) {
 			rpath[strlen(rpath) - 1] = part;
 
 			fd = open(rpath, O_RDONLY|O_CLOEXEC);
-			if (fd < 0) {
+			if (fd == -1) {
 				if (verbose)
 					warn("%s", rpath);
 				return (NULL);
@@ -125,7 +125,7 @@ readlabelfs(char *device, int verbose)
 
 disklabel:
 
-	if (ioctl(fd, DIOCGDINFO, &dk) < 0) {
+	if (ioctl(fd, DIOCGDINFO, &dk) == -1) {
 		if (verbose)
 			warn("%s: couldn't read disklabel", rpath);
 		close(fd);

src/lib/libutil/uucplock.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: uucplock.c,v 1.19 2016/08/30 14:52:09 guenther Exp $	*/
+/*	$OpenBSD: uucplock.c,v 1.20 2019/06/28 13:32:43 deraadt Exp $	*/
 /*
  * Copyright (c) 1988, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -71,11 +71,11 @@ uu_lock(const char *ttyname)
 	(void)snprintf(lckname, sizeof(lckname), _PATH_UUCPLOCK LOCKFMT,
 	    ttyname);
 	tmpfd = open(lcktmpname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664);
-	if (tmpfd < 0)
+	if (tmpfd == -1)
 		GORET(0, UU_LOCK_CREAT_ERR);
 
 	for (i = 0; i < MAXTRIES; i++) {
-		if (link(lcktmpname, lckname) < 0) {
+		if (link(lcktmpname, lckname) == -1) {
 			if (errno != EEXIST)
 				GORET(1, UU_LOCK_LINK_ERR);
 			/*
@@ -83,7 +83,7 @@ uu_lock(const char *ttyname)
 			 * check to see if the process holding the lock
 			 * still exists
 			 */
-			if ((fd = open(lckname, O_RDONLY | O_CLOEXEC)) < 0)
+			if ((fd = open(lckname, O_RDONLY | O_CLOEXEC)) == -1)
 				GORET(1, UU_LOCK_OPEN_ERR);
 
 			if ((pid_old = get_pid(fd, &err)) == -1)
@@ -127,7 +127,7 @@ uu_lock_txfr(const char *ttyname, pid_t pid)
 
 	snprintf(lckname, sizeof(lckname), _PATH_UUCPLOCK LOCKFMT, ttyname);
 
-	if ((fd = open(lckname, O_RDWR | O_CLOEXEC)) < 0)
+	if ((fd = open(lckname, O_RDWR | O_CLOEXEC)) == -1)
 		return UU_LOCK_OWNER_ERR;
 	if (get_pid(fd, &err) != getpid())
 		ret = UU_LOCK_OWNER_ERR;

src/usr.sbin/ntpd/constraint.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: constraint.c,v 1.46 2019/06/16 07:36:25 otto Exp $	*/
+/*	$OpenBSD: constraint.c,v 1.47 2019/06/28 13:32:49 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org>
@@ -955,7 +955,7 @@ httpsdate_request(struct httpsdate *httpsdate, struct timeval *when)
 		ret = tls_write(httpsdate->tls_ctx, buf, len);
 		if (ret == TLS_WANT_POLLIN || ret == TLS_WANT_POLLOUT)
 			continue;
-		if (ret < 0) {
+		if (ret == -1) {
 			log_warnx("tls write failed: %s (%s): %s",
 			    httpsdate->tls_addr, httpsdate->tls_hostname,
 			    tls_error(httpsdate->tls_ctx));
@@ -1091,7 +1091,7 @@ tls_readline(struct tls *tls, size_t *lenp, size_t *maxlength,
 		ret = tls_read(tls, &c, 1);
 		if (ret == TLS_WANT_POLLIN || ret == TLS_WANT_POLLOUT)
 			goto again;
-		if (ret < 0) {
+		if (ret == -1) {
 			/* SSL read error, ignore */
 			free(buf);
 			return (NULL);

src/usr.sbin/ntpd/ntpd.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: ntpd.c,v 1.123 2019/06/27 15:18:42 otto Exp $ */
+/*	$OpenBSD: ntpd.c,v 1.124 2019/06/28 13:32:49 deraadt Exp $ */
 
 /*
  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
@@ -111,7 +111,7 @@ auto_preconditions(const struct ntpd_conf *cnf)
 	int constraints, securelevel;
 	size_t sz = sizeof(int);
 
-	if (sysctl(mib, 2, &securelevel, &sz, NULL, 0) < 0)
+	if (sysctl(mib, 2, &securelevel, &sz, NULL, 0) == -1)
 		err(1, "sysctl");
 	constraints = !TAILQ_EMPTY(&cnf->constraints);
 	return !cnf->settime && constraints && securelevel == 0;