File 0003-tools-Run-as-FRR_USER-install-chown-comman... of Package frr

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File 0003-tools-Run-as-FRR_USER-install-chown-commands-to-avoi.patch of Package frr

From 401053f3ccc7be3a6a976f6f7f1674bdeb3c983e Mon Sep 17 00:00:00 2001
From: Donatas Abraitis <donatas@opensourcerouting.org>
Date: Thu, 20 Oct 2022 09:10:22 +0300
References: bsc#1204124,CVE-2022-42917,https://github.com/FRRouting/frr/pull/12157
Upstream: submitted
Subject: [PATCH] tools: Run as FRR_USER `install/chown` commands to avoid race
 conditions

This is due to CVE-2022-42917: https://bugzilla.suse.com/show_bug.cgi?id=1204124

install/chown is in most cases (as I tested) is enough, but still, can be racy.

Tested on Linux/OpenBSD/NetBSD/FreeBSD, seems a unified way to do this.

For Linux `runuser` can be used, but *BSD do not have this command.

Proof of concept:

```
% sudo su - frr
[sudo] password for donatas:
su: warning: cannot change directory to /nonexistent: No such file or directory
frr@donatas-laptop:/home/donatas$ cd /etc/frr/
frr@donatas-laptop:/etc/frr$ rm -f zebra.conf; inotifywait -e CREATE .; rm -f zebra.conf; ln -s /etc/shadow zebra.conf
Setting up watches.
Watches established.
./ CREATE zebra.conf
frr@donatas-laptop:/etc/frr$ ls -la zebra.conf
lrwxrwxrwx 1 frr frr 11 spal.  20 09:25 zebra.conf -> /etc/shadow
frr@donatas-laptop:/etc/frr$ cat zebra.conf
cat: zebra.conf: Permission denied
frr@donatas-laptop:/etc/frr$
```

On the other terminal do:

```
/usr/lib/frr/frrinit.sh restart
```

Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>

diff --git a/tools/frr.in b/tools/frr.in
index e9f1122834..5f3f425a1e 100755
--- a/tools/frr.in
+++ b/tools/frr.in
@@ -96,10 +96,10 @@ check_daemon()
 		# check for config file
 		if [ -n "$2" ]; then
 			if [ ! -r "$C_PATH/$1-$2.conf" ]; then
-				install -g "$FRR_GROUP" -o "$FRR_USER" -m "$FRR_CONFIG_MODE" /dev/null "$C_PATH/$1-$2.conf"
+				su - "${FRR_USER}" -c "install -g \"$FRR_GROUP\" -o \"$FRR_USER\" -m \"$FRR_CONFIG_MODE\" /dev/null \"$C_PATH/$1-$2.conf\""
 			fi
 		elif [ ! -r "$C_PATH/$1.conf" ]; then
-			install -g "$FRR_GROUP" -o "$FRR_USER" -m "$FRR_CONFIG_MODE" /dev/null "$C_PATH/$1.conf"
+			su - "${FRR_USER}" -c "install -g \"$FRR_GROUP\" -o \"$FRR_USER\" -m \"$FRR_CONFIG_MODE\" /dev/null \"$C_PATH/$1.conf\""
 		fi
 	fi
 	return 0
@@ -524,7 +524,7 @@ convert_daemon_prios
 
 if [ ! -d $V_PATH ]; then
 	echo "Creating $V_PATH"
-	install -g "$FRR_GROUP" -o "$FRR_USER" -m "$FRR_CONFIG_MODE" -d "$V_PATH"
+	su - "${FRR_USER}" -c "install -g \"$FRR_GROUP\" -o \"$FRR_USER\" -m \"$FRR_CONFIG_MODE\" -d \"$V_PATH\""
 	chmod gu+x "${V_PATH}"
 fi
 
diff --git a/tools/frrcommon.sh.in b/tools/frrcommon.sh.in
index 61f1abb378..4d5d688d57 100755
--- a/tools/frrcommon.sh.in
+++ b/tools/frrcommon.sh.in
@@ -143,7 +143,7 @@ daemon_prep() {
 
 	cfg="$C_PATH/$daemon${inst:+-$inst}.conf"
 	if [ ! -r "$cfg" ]; then
-		install -g "$FRR_GROUP" -o "$FRR_USER" -m "$FRR_CONFIG_MODE" /dev/null "$cfg"
+		su - "${FRR_USER}" -c "install -g \"$FRR_GROUP\" -o \"$FRR_USER\" -m \"$FRR_CONFIG_MODE\" /dev/null \"$cfg\""
 	fi
 	return 0
 }
@@ -161,7 +161,7 @@ daemon_start() {
 	[ "$MAX_FDS" != "" ] && ulimit -n "$MAX_FDS" > /dev/null 2> /dev/null
 	daemon_prep "$daemon" "$inst" || return 1
 	if test ! -d "$V_PATH"; then
-		install -g "$FRR_GROUP" -o "$FRR_USER" -m "$FRR_CONFIG_MODE" -d "$V_PATH"
+		su - "${FRR_USER}" -c "install -g \"$FRR_GROUP\" -o \"$FRR_USER\" -m \"$FRR_CONFIG_MODE\" -d \"$V_PATH\""
 		chmod gu+x "${V_PATH}"
 	fi
 
-- 
2.35.3

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File 0003-tools-Run-as-FRR_USER-install-chown-commands-to-avoi.patch of Package frr

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