Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging

Some trivial fixes/cleanup and a fix to cause QEMU to error out gracefully
instead of aborting.

# gpg: Signature made Tue 05 Sep 2017 16:57:19 BST
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "[jpeg image of size 3330]"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  virtfs: error out gracefully when mandatory suboptions are missing
  9pfs: local: clarify fchmodat_nofollow() implementation
  fsdev: fix memory leak in main()
  9pfs: avoid sign conversion error simplifying the code

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 22 insertions, 14 deletions

diff --git a/fsdev/virtfs-proxy-helper.c b/fsdev/virtfs-proxy-helper.c
index 6c066ec9a0..8e48500dd5 100644
--- a/fsdev/virtfs-proxy-helper.c
+++ b/fsdev/virtfs-proxy-helper.c
@@ -1162,6 +1162,8 @@ int main(int argc, char **argv)
 
     process_requests(sock);
 error:
+    g_free(rpath);
+    g_free(sock_name);
     do_log(LOG_INFO, "Done\n");
     closelog();
     return 0;
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
index efb0b79a74..e51af87309 100644
--- a/hw/9pfs/9p-local.c
+++ b/hw/9pfs/9p-local.c
@@ -349,11 +349,11 @@ static int fchmodat_nofollow(int dirfd, const char *name, mode_t mode)
         return -1;
     }
 
-    /* Access modes are ignored when O_PATH is supported. We try O_RDONLY and
-     * O_WRONLY for old-systems that don't support O_PATH.
-     */
-    fd = openat_file(dirfd, name, O_RDONLY | O_PATH_9P_UTIL, 0);
+    fd = openat_file(dirfd, name, O_RDONLY | O_PATH_9P_UTIL | O_NOFOLLOW, 0);
 #if O_PATH_9P_UTIL == 0
+    /* Fallback for systems that don't support O_PATH: we depend on the file
+     * being readable or writable.
+     */
     if (fd == -1) {
         /* In case the file is writable-only and isn't a directory. */
         if (errno == EACCES) {
@@ -368,6 +368,10 @@ static int fchmodat_nofollow(int dirfd, const char *name, mode_t mode)
     }
     ret = fchmod(fd, mode);
 #else
+    /* Access modes are ignored when O_PATH is supported. If name is a symbolic
+     * link, O_PATH | O_NOFOLLOW causes openat(2) to return a file descriptor
+     * referring to the symbolic link.
+     */
     if (fd == -1) {
         return -1;
     }
diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index 333dbb6f8e..0a37c8bd13 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -945,7 +945,6 @@ static void coroutine_fn v9fs_version(void *opaque)
     v9fs_string_init(&version);
     err = pdu_unmarshal(pdu, offset, "ds", &s->msize, &version);
     if (err < 0) {
-        offset = err;
         goto out;
     }
     trace_v9fs_version(pdu->tag, pdu->id, s->msize, version.data);
@@ -962,13 +961,12 @@ static void coroutine_fn v9fs_version(void *opaque)
 
     err = pdu_marshal(pdu, offset, "ds", s->msize, &version);
     if (err < 0) {
-        offset = err;
         goto out;
     }
-    offset += err;
+    err += offset;
     trace_v9fs_version_return(pdu->tag, pdu->id, s->msize, version.data);
 out:
-    pdu_complete(pdu, offset);
+    pdu_complete(pdu, err);
     v9fs_string_free(&version);
 }
 
diff --git a/vl.c b/vl.c
index 0b45e1b6fa..e75757f977 100644
--- a/vl.c
+++ b/vl.c
@@ -3557,7 +3557,7 @@ int main(int argc, char **argv, char **envp)
             case QEMU_OPTION_virtfs: {
                 QemuOpts *fsdev;
                 QemuOpts *device;
-                const char *writeout, *sock_fd, *socket;
+                const char *writeout, *sock_fd, *socket, *path, *security_model;
 
                 olist = qemu_find_opts("virtfs");
                 if (!olist) {
@@ -3596,11 +3596,15 @@ int main(int argc, char **argv, char **envp)
                 }
                 qemu_opt_set(fsdev, "fsdriver",
                              qemu_opt_get(opts, "fsdriver"), &error_abort);
-                qemu_opt_set(fsdev, "path", qemu_opt_get(opts, "path"),
-                             &error_abort);
-                qemu_opt_set(fsdev, "security_model",
-                             qemu_opt_get(opts, "security_model"),
-                             &error_abort);
+                path = qemu_opt_get(opts, "path");
+                if (path) {
+                    qemu_opt_set(fsdev, "path", path, &error_abort);
+                }
+                security_model = qemu_opt_get(opts, "security_model");
+                if (security_model) {
+                    qemu_opt_set(fsdev, "security_model", security_model,
+                                 &error_abort);
+                }
                 socket = qemu_opt_get(opts, "socket");
                 if (socket) {
                     qemu_opt_set(fsdev, "socket", socket, &error_abort);