From: Tudor Florea <[email protected]> fusermount in FUSE before 2.9.3-15 does not properly clear the environment before invoking (1) mount or (2) umount as root, which allows local users to write to arbitrary files via a crafted LIBMOUNT_MTAB environment variable that is used by mount's debugging feature.
References: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-3202 http://www.openwall.com/lists/oss-security/2015/05/21/9 Signed-off-by: Tudor Florea <[email protected]> Signed-off-by: Martin Jansa <[email protected]> Signed-off-by: Armin Kuster <[email protected]> --- ...fix_exec_environment_for_mount_and_umount.patch | 63 ++++++++++++++++++++++ .../recipes-support/fuse/fuse_2.9.3.bb | 1 + 2 files changed, 64 insertions(+) create mode 100644 meta-filesystems/recipes-support/fuse/files/001-fix_exec_environment_for_mount_and_umount.patch diff --git a/meta-filesystems/recipes-support/fuse/files/001-fix_exec_environment_for_mount_and_umount.patch b/meta-filesystems/recipes-support/fuse/files/001-fix_exec_environment_for_mount_and_umount.patch new file mode 100644 index 0000000..8332bfb --- /dev/null +++ b/meta-filesystems/recipes-support/fuse/files/001-fix_exec_environment_for_mount_and_umount.patch @@ -0,0 +1,63 @@ +From cfe13b7a217075ae741c018da50cd600e5330de2 Mon Sep 17 00:00:00 2001 +From: Miklos Szeredi <[email protected]> +Date: Fri, 22 May 2015 10:58:43 +0200 +Subject: [PATCH] libfuse: fix exec environment for mount and umount + +Found by Tavis Ormandy (CVE-2015-3202). + +Upstream-Status: Submitted +Signed-off-by: Tudor Florea <[email protected]> + +--- +--- a/lib/mount_util.c ++++ b/lib/mount_util.c +@@ -95,10 +95,12 @@ static int add_mount(const char *prognam + goto out_restore; + } + if (res == 0) { ++ char *env = NULL; ++ + sigprocmask(SIG_SETMASK, &oldmask, NULL); + setuid(geteuid()); +- execl("/bin/mount", "/bin/mount", "--no-canonicalize", "-i", +- "-f", "-t", type, "-o", opts, fsname, mnt, NULL); ++ execle("/bin/mount", "/bin/mount", "--no-canonicalize", "-i", ++ "-f", "-t", type, "-o", opts, fsname, mnt, NULL, &env); + fprintf(stderr, "%s: failed to execute /bin/mount: %s\n", + progname, strerror(errno)); + exit(1); +@@ -146,10 +148,17 @@ static int exec_umount(const char *progn + goto out_restore; + } + if (res == 0) { ++ char *env = NULL; ++ + sigprocmask(SIG_SETMASK, &oldmask, NULL); + setuid(geteuid()); +- execl("/bin/umount", "/bin/umount", "-i", rel_mnt, +- lazy ? "-l" : NULL, NULL); ++ if (lazy) { ++ execle("/bin/umount", "/bin/umount", "-i", rel_mnt, ++ "-l", NULL, &env); ++ } else { ++ execle("/bin/umount", "/bin/umount", "-i", rel_mnt, ++ NULL, &env); ++ } + fprintf(stderr, "%s: failed to execute /bin/umount: %s\n", + progname, strerror(errno)); + exit(1); +@@ -205,10 +214,12 @@ static int remove_mount(const char *prog + goto out_restore; + } + if (res == 0) { ++ char *env = NULL; ++ + sigprocmask(SIG_SETMASK, &oldmask, NULL); + setuid(geteuid()); +- execl("/bin/umount", "/bin/umount", "--no-canonicalize", "-i", +- "--fake", mnt, NULL); ++ execle("/bin/umount", "/bin/umount", "--no-canonicalize", "-i", ++ "--fake", mnt, NULL, &env); + fprintf(stderr, "%s: failed to execute /bin/umount: %s\n", + progname, strerror(errno)); + exit(1); diff --git a/meta-filesystems/recipes-support/fuse/fuse_2.9.3.bb b/meta-filesystems/recipes-support/fuse/fuse_2.9.3.bb index 60fea87..2e2f7a1 100644 --- a/meta-filesystems/recipes-support/fuse/fuse_2.9.3.bb +++ b/meta-filesystems/recipes-support/fuse/fuse_2.9.3.bb @@ -13,6 +13,7 @@ LIC_FILES_CHKSUM = "file://COPYING;md5=b234ee4d69f5fce4486a80fdaf4a4263 \ SRC_URI = "${SOURCEFORGE_MIRROR}/fuse/fuse-${PV}.tar.gz \ file://gold-unversioned-symbol.patch \ file://aarch64.patch \ + file://001-fix_exec_environment_for_mount_and_umount.patch \ " SRC_URI[md5sum] = "33cae22ca50311446400daf8a6255c6a" SRC_URI[sha256sum] = "0beb83eaf2c5e50730fc553406ef124d77bc02c64854631bdfc86bfd6437391c" -- 1.9.1 -- _______________________________________________ Openembedded-devel mailing list [email protected] http://lists.openembedded.org/mailman/listinfo/openembedded-devel
