OS-6097 snoop reports "Is a directory" for non-existent VNIC

Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Approved by: Jerry Jelinek <jerry.jelinek@joyent.com>

4 files changed, 140 insertions, 6 deletions

diff --git a/usr/src/lib/libdlpi/common/libdlpi.c b/usr/src/lib/libdlpi/common/libdlpi.c
index aa97afee04..d07eea70e7 100644
--- a/usr/src/lib/libdlpi/common/libdlpi.c
+++ b/usr/src/lib/libdlpi/common/libdlpi.c
@@ -23,7 +23,7 @@
  * Use is subject to license terms.
  */
 /*
- * Copyright (c) 2014, Joyent, Inc.
+ * Copyright (c) 2017, Joyent, Inc.
  */
 
 /*
@@ -1088,10 +1088,12 @@ i_dlpi_open(const char *provider, const char *zonename, int *fd, uint_t flags,
 			(void) snprintf(path, sizeof (path), "/dev/ipnet/%s",
 			    provider);
 		}
-		if ((*fd = open(path, oflags)) != -1)
+		if ((*fd = open(path, oflags)) != -1) {
 			return (DLPI_SUCCESS);
-		else
-			return (errno == ENOENT ? DLPI_ENOLINK : DL_SYSERR);
+		} else {
+			return (errno == ENOENT || errno == EISDIR ?
+			    DLPI_ENOLINK : DL_SYSERR);
+		}
 	} else if (style1 && !(flags & DLPI_DEVONLY)) {
 		char		driver[DLPI_LINKNAME_MAX];
 		char		device[DLPI_LINKNAME_MAX];
@@ -1160,7 +1162,7 @@ fallback:
 	if ((*fd = open(path, oflags)) != -1)
 		return (DLPI_SUCCESS);
 
-	return (errno == ENOENT ? DLPI_ENOLINK : DL_SYSERR);
+	return (errno == ENOENT || errno == EISDIR ? DLPI_ENOLINK : DL_SYSERR);
 }
 
 /*
diff --git a/usr/src/test/os-tests/runfiles/default.run b/usr/src/test/os-tests/runfiles/default.run
index eca82268c0..db212b8113 100644
--- a/usr/src/test/os-tests/runfiles/default.run
+++ b/usr/src/test/os-tests/runfiles/default.run
@@ -58,3 +58,6 @@ tests = ['tmpfs_badmount', 'tmpfs_enospc']
 
 [/opt/os-tests/tests/file-locking]
 tests = ['runtests.32', 'runtests.64']
+
+[/opt/os-tests/tests/OS-6097.32]
+[/opt/os-tests/tests/OS-6097.64]
diff --git a/usr/src/test/os-tests/tests/Makefile b/usr/src/test/os-tests/tests/Makefile
index b4330ae706..c0391d45bd 100644
--- a/usr/src/test/os-tests/tests/Makefile
+++ b/usr/src/test/os-tests/tests/Makefile
@@ -16,4 +16,59 @@
 
 SUBDIRS = poll secflags sigqueue spoof-ras sdevfs timer tmpfs file-locking
 
-include $(SRC)/test/Makefile.com
+PROGS = \
+	OS-6097
+
+PROGS32 = $(PROGS:%=%.32)
+PROGS64 = $(PROGS:%=%.64)
+
+OS-6097.32 :=	LDLIBS += -ldlpi
+OS-6097.64 :=	LDLIBS64 += -ldlpi
+
+ROOTOPTDIR = $(ROOT)/opt/os-tests/tests
+ROOTOPTPROGS = $(PROGS32:%=$(ROOTOPTDIR)/%) \
+	$(PROGS64:%=$(ROOTOPTDIR)/%) \
+	$(SCRIPTS:%=$(ROOTOPTDIR)/%)
+
+include $(SRC)/cmd/Makefile.cmd
+
+all     :=      TARGET = all
+install :=      TARGET = install
+clean   :=      TARGET = clean
+clobber :=      TARGET = clobber
+lint    :=      TARGET = lint
+
+.KEEP_STATE:
+
+install: $(SUBDIRS) $(ROOTOPTPROGS)
+
+all: $(SUBDIRS) $(PROGS32) $(PROGS64)
+
+clean lint: $(SUBDIRS)
+
+$(ROOTOPTPROGS): $(PROGS32) $(PROGS64) $(ROOTOPTDIR)
+
+$(ROOTOPTDIR):
+	$(INS.dir)
+
+$(ROOTOPTDIR)/%: %
+	$(INS.file)
+
+$(ROOTOPTDIR)/%: %.ksh
+	$(INS.rename)
+
+%.64: %.c
+	$(LINK64.c) -o $@ $< $(LDLIBS64)
+	$(POST_PROCESS)
+
+%.32: %.c
+	$(LINK.c) -o $@ $< $(LDLIBS)
+	$(POST_PROCESS)
+
+clobber: $(SUBDIRS)
+	$(RM) $(PROGS32) $(PROGS64)
+
+$(SUBDIRS): FRC
+	@cd $@; pwd; $(MAKE) $(TARGET)
+
+FRC:
diff --git a/usr/src/test/os-tests/tests/OS-6097.c b/usr/src/test/os-tests/tests/OS-6097.c
new file mode 100644
index 0000000000..160c01e9c7
--- /dev/null
+++ b/usr/src/test/os-tests/tests/OS-6097.c
@@ -0,0 +1,74 @@
+/*
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ */
+
+/*
+ * Copyright (c) 2017, Joyent, Inc.
+ */
+
+/*
+ * Regression test for OS-6097.
+ */
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <libdlpi.h>
+#include <sys/debug.h>
+
+int
+main(void)
+{
+	int ret;
+	char path[4096];
+	uint_t num = 4294967294U;
+	dlpi_handle_t dh;
+
+	/*
+	 * First, we need to determine a path that doesn't exist to trigger this
+	 * bug. We start with the highest possible number and just decrement
+	 * until we find something.
+	 */
+
+	while (num > 0) {
+		struct stat st;
+
+		(void) snprintf(path, sizeof (path), "/dev/net/net%u", num);
+
+		ret = stat(path, &st);
+		if (ret == -1 && errno == ENOENT)
+			break;
+		if (ret == -1) {
+			(void) fprintf(stderr, "test failed: unexpected error "
+			    "running stat(2) on %s: %s\n", path,
+			    strerror(errno));
+			return (1);
+		}
+		num--;
+	}
+
+	/*
+	 * While technically this is a valid entry that we could try, at this
+	 * point we've exhausted so many NICs, there's likely a bug.
+	 */
+	if (num == 0) {
+		(void) fprintf(stderr, "failed to construct a non-existent "
+		    "NIC with a name starting with 'net'\n");
+		return (1);
+	}
+
+	(void) snprintf(path, sizeof (path), "net%u", num);
+	ret = dlpi_open(path, &dh, 0);
+	VERIFY3U(ret, ==, DLPI_ENOLINK);
+	return (0);
+}