From 94b18b8123b5d957ed84e4aa8e268b60f5427821 Mon Sep 17 00:00:00 2001

From: Filipe Brandenburger <filbranden@google.com>

Date: Tue, 17 Jul 2018 11:32:40 -0700

Subject: [PATCH] bus-socket: Fix line_begins() to accept word matching full

 string

The switch to memory_startswith() changed the logic to only look for a space or

NUL byte after the matched word, but matching the full size should also be

acceptable.

This changed the behavior of parsing of "AUTH\r\n", where m will be set to 4,

since even though the word will match, the check for it being followed by ' '

or NUL will make line_begins() return false.

Tested:

- Using netcat to connect to the private socket directly:

  $ echo -ne '\0AUTH\r\n' | sudo nc -U /run/systemd/private

  REJECTED EXTERNAL ANONYMOUS

- Running the Ignition blackbox test:

  $ sudo sh -c 'PATH=$PWD/bin/amd64:$PATH ./tests.test'

  PASS

Fixes: d27b725abf64a19a6b2f99332b663f17ad046771

(cherry picked from commit 3f10c66270b74530339b3f466c43874bb40c210f)

Resolves: #1692991

---

 src/libsystemd/sd-bus/bus-socket.c | 5 +----

 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/libsystemd/sd-bus/bus-socket.c b/src/libsystemd/sd-bus/bus-socket.c

index b147a3843a..a5513d1ab5 100644

--- a/src/libsystemd/sd-bus/bus-socket.c

+++ b/src/libsystemd/sd-bus/bus-socket.c

@@ -248,10 +248,7 @@ static bool line_begins(const char *s, size_t m, const char *word) {

         const char *p;

         p = memory_startswith(s, m, word);

-        if (!p)

-                return false;

-

-        return IN_SET(*p, 0, ' ');

+        return p && (p == (s + m) || *p == ' ');

 }

 static int verify_anonymous_token(sd_bus *b, const char *p, size_t l) {