From: Michael Tremer <michael.tremer@ipfire.org>
Date: Tue, 2 Aug 2022 16:01:40 +0000 (+0000)
Subject: mount: Fix mounting any file systems from the host system
X-Git-Tag: 0.9.28~628
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9ab7dd216d46b2547ecc783719621cccc7144943;p=pakfire.git

mount: Fix mounting any file systems from the host system

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/mount.c b/src/libpakfire/mount.c
index bff245f97..5682b6c25 100644
--- a/src/libpakfire/mount.c
+++ b/src/libpakfire/mount.c
@@ -43,25 +43,43 @@ static const struct pakfire_mountpoint {
 	int flags;
 	const char* options;
 } mountpoints[] = {
-	{ "pakfire_proc",  "proc",         "proc",  MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL, },
-
-	// Bind mount /proc/sys as read-only with the following exceptions:
-	//  * /proc/sys/net
-	{ "/proc/sys",     "proc/sys",     "bind",  MS_BIND, NULL, },
-	{ "/proc/sys/net", "proc/sys/net", "bind",  MS_BIND, NULL, },
-	{ "/proc/sys",     "proc/sys",     "bind",  MS_BIND|MS_RDONLY|MS_REMOUNT, NULL, },
-
-	// Bind mount /sys as read-only
-	{ "/sys",          "sys",          "bind",  MS_BIND, NULL, },
-	{ "/sys",          "sys",          "bind",  MS_BIND|MS_RDONLY|MS_REMOUNT, NULL, },
+	// Mount a new instance of /proc
+	{ "pakfire_proc",        "proc",               "proc",
+		MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL, },
+
+	// Make /proc/sys read-only (except /proc/sys/net)
+	{ "/proc/sys",           "proc/sys",           "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/proc/sys/net",       "proc/sys/net",       "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/proc/sys",           "proc/sys",           "bind",
+		MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL, },
+
+	// Deny write access to /proc/sysrq-trigger (can be used to restart the host)
+	{ "/proc/sysrq-trigger", "proc/sysrq-trigger", "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/proc/sysrq-trigger", "proc/sysrq-trigger", "bind",
+		MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL, },
+
+	// Make /proc/irq read-only
+	{ "/proc/irq",           "proc/irq",           "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/proc/irq",           "proc/irq",           "bind",
+		MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL, },
+
+	// Make /proc/bus read-only
+	{ "/proc/bus",           "proc/bus",           "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/proc/bus",           "proc/bus",           "bind",
+		MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL, },
+
+	// Bind-Mount /sys ready-only
+	{ "/sys",                "sys",                "bind",  MS_BIND|MS_REC, NULL, },
+	{ "/sys",                "sys",                "bind",
+		MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL, },
 
 	// Create a new /dev
-	{ "pakfire_dev",   "dev",          "tmpfs", MS_NOSUID|MS_NOEXEC,
-		"mode=755,size=4m,nr_inodes=64k", },
-	{ "/dev/pts",      "dev/pts",      "bind",  MS_BIND, NULL, },
+	{ "pakfire_dev",         "dev",                "tmpfs", MS_NOSUID|MS_NOEXEC,
+		"mode=0755,size=4m,nr_inodes=64k", },
+	{ "/dev/pts",            "dev/pts",            "bind",  MS_BIND, NULL, },
 
 	// Create a new /run
-	{ "pakfire_tmpfs", "run",          "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+	{ "pakfire_tmpfs",       "run",                "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV,
 		"mode=755,size=4m,nr_inodes=1k", },
 
 	// The end