qemu: Several CVE fixes

Source: qemu.org
MR: 97258, 97342, 97438, 97443
Type: Security Fix
Disposition: Backport from git.qemu.org/qemu.git
ChangeID: a5e9fd03ca5bebc880dcc3c4567e10a9ae47dba5
Description:

These issues affect qemu < 3.1.0

Fixes:
CVE-2018-16867
CVE-2018-16872
CVE-2018-18849
CVE-2018-19364

(From OE-Core rev: e3dfe53a334cd952cc2194fd3baad6d082659b7e)

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 89 insertions, 0 deletions

diff --git a/meta/recipes-devtools/qemu/qemu/CVE-2018-16872.patch b/meta/recipes-devtools/qemu/qemu/CVE-2018-16872.patch
new file mode 100644
index 0000000000..9f2c5d3ec1
--- /dev/null
+++ b/meta/recipes-devtools/qemu/qemu/CVE-2018-16872.patch
@@ -0,0 +1,89 @@
+From 7347a04da35ec6284ce83e8bcd72dc4177d17b10 Mon Sep 17 00:00:00 2001
+From: Gerd Hoffmann <kraxel@redhat.com>
+Date: Thu, 13 Dec 2018 13:25:11 +0100
+Subject: [PATCH] usb-mtp: use O_NOFOLLOW and O_CLOEXEC.
+
+Open files and directories with O_NOFOLLOW to avoid symlinks attacks.
+While being at it also add O_CLOEXEC.
+
+usb-mtp only handles regular files and directories and ignores
+everything else, so users should not see a difference.
+
+Because qemu ignores symlinks, carrying out a successful symlink attack
+requires swapping an existing file or directory below rootdir for a
+symlink and winning the race against the inotify notification to qemu.
+
+Fixes: CVE-2018-16872
+Cc: Prasad J Pandit <ppandit@redhat.com>
+Cc: Bandan Das <bsd@redhat.com>
+Reported-by: Michael Hanselmann <public@hansmi.ch>
+Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
+Reviewed-by: Michael Hanselmann <public@hansmi.ch>
+Message-id: 20181213122511.13853-1-kraxel@redhat.com
+(cherry picked from commit bab9df35ce73d1c8e19a37e2737717ea1c984dc1)
+Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
+
+Upstream-Status: Backport
+CVE: CVE-2018-16872
+Affects: < 3.1.0
+
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ hw/usb/dev-mtp.c | 13 +++++++++----
+ 1 file changed, 9 insertions(+), 4 deletions(-)
+
+diff --git a/hw/usb/dev-mtp.c b/hw/usb/dev-mtp.c
+index 899c8a3..f4223fb 100644
+--- a/hw/usb/dev-mtp.c
++++ b/hw/usb/dev-mtp.c
+@@ -649,13 +649,18 @@ static void usb_mtp_object_readdir(MTPState *s, MTPObject *o)
+ {
+     struct dirent *entry;
+     DIR *dir;
++    int fd;
+ 
+     if (o->have_children) {
+         return;
+     }
+     o->have_children = true;
+ 
+-    dir = opendir(o->path);
++    fd = open(o->path, O_DIRECTORY | O_CLOEXEC | O_NOFOLLOW);
++    if (fd < 0) {
++        return;
++    }
++    dir = fdopendir(fd);
+     if (!dir) {
+         return;
+     }
+@@ -1003,7 +1008,7 @@ static MTPData *usb_mtp_get_object(MTPState *s, MTPControl *c,
+ 
+     trace_usb_mtp_op_get_object(s->dev.addr, o->handle, o->path);
+ 
+-    d->fd = open(o->path, O_RDONLY);
++    d->fd = open(o->path, O_RDONLY | O_CLOEXEC | O_NOFOLLOW);
+     if (d->fd == -1) {
+         usb_mtp_data_free(d);
+         return NULL;
+@@ -1027,7 +1032,7 @@ static MTPData *usb_mtp_get_partial_object(MTPState *s, MTPControl *c,
+                                         c->argv[1], c->argv[2]);
+ 
+     d = usb_mtp_data_alloc(c);
+-    d->fd = open(o->path, O_RDONLY);
++    d->fd = open(o->path, O_RDONLY | O_CLOEXEC | O_NOFOLLOW);
+     if (d->fd == -1) {
+         usb_mtp_data_free(d);
+         return NULL;
+@@ -1608,7 +1613,7 @@ static void usb_mtp_write_data(MTPState *s)
+                                  0, 0, 0, 0);
+             goto done;
+         }
+-        d->fd = open(path, O_CREAT | O_WRONLY, mask);
++        d->fd = open(path, O_CREAT | O_WRONLY | O_CLOEXEC | O_NOFOLLOW, mask);
+         if (d->fd == -1) {
+             usb_mtp_queue_result(s, RES_STORE_FULL, d->trans,
+                                  0, 0, 0, 0);
+-- 
+2.7.4
+