package/systemd: add upstream security fixes

CVE-2019-6454: systemd (PID1) crash with specially crafted D-Bus message
from unprivileged user

Cc: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
Cc: Yann E. MORIN <yann.morin.1998@free.fr>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/package/systemd/0018-Refuse-dbus-message-paths-longer-than-BUS_PATH_SIZE_.patch b/package/systemd/0018-Refuse-dbus-message-paths-longer-than-BUS_PATH_SIZE_.patch
new file mode 100644
index 0000000000..2de3b71b5c
--- /dev/null
+++ b/package/systemd/0018-Refuse-dbus-message-paths-longer-than-BUS_PATH_SIZE_.patch
@@ -0,0 +1,53 @@
+From febef5e18558c114f4fb7c94f6c8ed3520c50cdf Mon Sep 17 00:00:00 2001
+From: Riccardo Schirone <rschiron@redhat.com>
+Date: Mon, 4 Feb 2019 14:29:09 +0100
+Subject: [PATCH] Refuse dbus message paths longer than BUS_PATH_SIZE_MAX
+ limit.
+
+Even though the dbus specification does not enforce any length limit on the
+path of a dbus message, having to analyze too long strings in PID1 may be
+time-consuming and it may have security impacts.
+
+In any case, the limit is set so high that real-life applications should not
+have a problem with it.
+
+(cherry picked from commit 61397a60d98e368a5720b37e83f3169e3eb511c4)
+Signed-off-by: Baruch Siach <baruch@tkos.co.il>
+---
+Upstream status: commit 61397a60d98
+
+ src/libsystemd/sd-bus/bus-internal.c | 2 +-
+ src/libsystemd/sd-bus/bus-internal.h | 4 ++++
+ 2 files changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/src/libsystemd/sd-bus/bus-internal.c b/src/libsystemd/sd-bus/bus-internal.c
+index 40acae213381..598b7f110c73 100644
+--- a/src/libsystemd/sd-bus/bus-internal.c
++++ b/src/libsystemd/sd-bus/bus-internal.c
+@@ -43,7 +43,7 @@ bool object_path_is_valid(const char *p) {
+         if (slash)
+                 return false;
+ 
+-        return true;
++        return (q - p) <= BUS_PATH_SIZE_MAX;
+ }
+ 
+ char* object_path_startswith(const char *a, const char *b) {
+diff --git a/src/libsystemd/sd-bus/bus-internal.h b/src/libsystemd/sd-bus/bus-internal.h
+index f208b294d8f1..a8d61bf72a4e 100644
+--- a/src/libsystemd/sd-bus/bus-internal.h
++++ b/src/libsystemd/sd-bus/bus-internal.h
+@@ -332,6 +332,10 @@ struct sd_bus {
+ 
+ #define BUS_MESSAGE_SIZE_MAX (128*1024*1024)
+ #define BUS_AUTH_SIZE_MAX (64*1024)
++/* Note that the D-Bus specification states that bus paths shall have no size limit. We enforce here one
++ * anyway, since truly unbounded strings are a security problem. The limit we pick is relatively large however,
++ * to not clash unnecessarily with real-life applications. */
++#define BUS_PATH_SIZE_MAX (64*1024)
+ 
+ #define BUS_CONTAINER_DEPTH 128
+ 
+-- 
+2.20.1
+