From e3d4c6f38d1a531b2d9826ea50c9ff7f6ce1b301 Mon Sep 17 00:00:00 2001 From: David Michael Date: Fri, 8 Feb 2019 21:38:49 +0000 Subject: [PATCH] app-emulation/runc: Fix CVE-2019-5736 for Docker 1.12 --- .../docker/docker-1.12.6-r8.ebuild | 2 +- ...lf-exe-to-avoid-exposing-host-b_1.12.patch | 290 ++++++++++++++++++ ..._p9.ebuild => runc-1.0.0_rc2_p9-r1.ebuild} | 1 + .../app-torcx/docker/docker-1.12.ebuild | 4 +- .../md5-cache/app-emulation/docker-1.12.6-r8 | 4 +- ...runc-1.0.0_rc2_p9 => runc-1.0.0_rc2_p9-r1} | 2 +- .../metadata/md5-cache/app-torcx/docker-1.12 | 4 +- 7 files changed, 299 insertions(+), 8 deletions(-) create mode 100644 sdk_container/src/third_party/coreos-overlay/app-emulation/runc/files/0001-nsenter-clone-proc-self-exe-to-avoid-exposing-host-b_1.12.patch rename sdk_container/src/third_party/coreos-overlay/app-emulation/runc/{runc-1.0.0_rc2_p9.ebuild => runc-1.0.0_rc2_p9-r1.ebuild} (94%) rename sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/{runc-1.0.0_rc2_p9 => runc-1.0.0_rc2_p9-r1} (96%) diff --git a/sdk_container/src/third_party/coreos-overlay/app-emulation/docker/docker-1.12.6-r8.ebuild b/sdk_container/src/third_party/coreos-overlay/app-emulation/docker/docker-1.12.6-r8.ebuild index 634c1590fb..cc65d78483 100644 --- a/sdk_container/src/third_party/coreos-overlay/app-emulation/docker/docker-1.12.6-r8.ebuild +++ b/sdk_container/src/third_party/coreos-overlay/app-emulation/docker/docker-1.12.6-r8.ebuild @@ -62,7 +62,7 @@ RDEPEND=" >=sys-apps/shadow-4.4 =app-emulation/containerd-0.2.5-r3[seccomp?] - =app-emulation/runc-1.0.0_rc2_p9[apparmor?,seccomp?] + =app-emulation/runc-1.0.0_rc2_p9-r1[apparmor?,seccomp?] " RESTRICT="installsources strip" diff --git a/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/files/0001-nsenter-clone-proc-self-exe-to-avoid-exposing-host-b_1.12.patch b/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/files/0001-nsenter-clone-proc-self-exe-to-avoid-exposing-host-b_1.12.patch new file mode 100644 index 0000000000..6d85b3dcca --- /dev/null +++ b/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/files/0001-nsenter-clone-proc-self-exe-to-avoid-exposing-host-b_1.12.patch @@ -0,0 +1,290 @@ +From 122c65bee886dda4d7bcb0512816b65fc878dacb Mon Sep 17 00:00:00 2001 +From: Aleksa Sarai +Date: Wed, 9 Jan 2019 13:40:01 +1100 +Subject: [PATCH 1/1] nsenter: clone /proc/self/exe to avoid exposing host + binary to container + +There are quite a few circumstances where /proc/self/exe pointing to a +pretty important container binary is a _bad_ thing, so to avoid this we +have to make a copy (preferably doing self-clean-up and not being +writeable). + +As a hotfix we require memfd_create(2), but we can always extend this to +use a scratch MNT_DETACH overlayfs or tmpfs. The main downside to this +approach is no page-cache sharing for the runc binary (which overlayfs +would give us) but this is far less complicated. + +This is only done during nsenter so that it happens transparently to the +Go code, and any libcontainer users benefit from it. This also makes +ExtraFiles and --preserve-fds handling trivial (because we don't need to +worry about it). + +Fixes: CVE-2019-5736 +Co-developed-by: Christian Brauner +Signed-off-by: Aleksa Sarai +Signed-off-by: Mrunal Patel +--- + libcontainer/nsenter/cloned_binary.c | 221 +++++++++++++++++++++++++++ + libcontainer/nsenter/nsexec.c | 11 ++ + 2 files changed, 232 insertions(+) + create mode 100644 libcontainer/nsenter/cloned_binary.c + +diff --git a/libcontainer/nsenter/cloned_binary.c b/libcontainer/nsenter/cloned_binary.c +new file mode 100644 +index 00000000..d9f6093a +--- /dev/null ++++ b/libcontainer/nsenter/cloned_binary.c +@@ -0,0 +1,221 @@ ++#define _GNU_SOURCE ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++#include ++ ++/* Use our own wrapper for memfd_create. */ ++#if !defined(SYS_memfd_create) && defined(__NR_memfd_create) ++# define SYS_memfd_create __NR_memfd_create ++#endif ++#ifndef SYS_memfd_create ++# error "memfd_create(2) syscall not supported by this glibc version" ++#endif ++int memfd_create(const char *name, unsigned int flags) ++{ ++ return syscall(SYS_memfd_create, name, flags); ++} ++ ++/* This comes directly from . */ ++#ifndef F_LINUX_SPECIFIC_BASE ++# define F_LINUX_SPECIFIC_BASE 1024 ++#endif ++#ifndef F_ADD_SEALS ++# define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9) ++# define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10) ++#endif ++#ifndef F_SEAL_SEAL ++# define F_SEAL_SEAL 0x0001 /* prevent further seals from being set */ ++# define F_SEAL_SHRINK 0x0002 /* prevent file from shrinking */ ++# define F_SEAL_GROW 0x0004 /* prevent file from growing */ ++# define F_SEAL_WRITE 0x0008 /* prevent writes */ ++#endif ++ ++ ++#define OUR_MEMFD_COMMENT "runc_cloned:/proc/self/exe" ++#define OUR_MEMFD_SEALS \ ++ (F_SEAL_SEAL | F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE) ++ ++static void *must_realloc(void *ptr, size_t size) ++{ ++ void *old = ptr; ++ do { ++ ptr = realloc(old, size); ++ } while(!ptr); ++ return ptr; ++} ++ ++/* ++ * Verify whether we are currently in a self-cloned program (namely, is ++ * /proc/self/exe a memfd). F_GET_SEALS will only succeed for memfds (or rather ++ * for shmem files), and we want to be sure it's actually sealed. ++ */ ++static int is_self_cloned(void) ++{ ++ int fd, seals; ++ ++ fd = open("/proc/self/exe", O_RDONLY|O_CLOEXEC); ++ if (fd < 0) ++ return -ENOTRECOVERABLE; ++ ++ seals = fcntl(fd, F_GET_SEALS); ++ close(fd); ++ return seals == OUR_MEMFD_SEALS; ++} ++ ++/* ++ * Basic wrapper around mmap(2) that gives you the file length so you can ++ * safely treat it as an ordinary buffer. Only gives you read access. ++ */ ++static char *read_file(char *path, size_t *length) ++{ ++ int fd; ++ char buf[4096], *copy = NULL; ++ ++ if (!length) ++ return NULL; ++ ++ fd = open(path, O_RDONLY | O_CLOEXEC); ++ if (fd < 0) ++ return NULL; ++ ++ *length = 0; ++ for (;;) { ++ int n; ++ ++ n = read(fd, buf, sizeof(buf)); ++ if (n < 0) ++ goto error; ++ if (!n) ++ break; ++ ++ copy = must_realloc(copy, (*length + n) * sizeof(*copy)); ++ memcpy(copy + *length, buf, n); ++ *length += n; ++ } ++ close(fd); ++ return copy; ++ ++error: ++ close(fd); ++ free(copy); ++ return NULL; ++} ++ ++/* ++ * A poor-man's version of "xargs -0". Basically parses a given block of ++ * NUL-delimited data, within the given length and adds a pointer to each entry ++ * to the array of pointers. ++ */ ++static int parse_xargs(char *data, int data_length, char ***output) ++{ ++ int num = 0; ++ char *cur = data; ++ ++ if (!data || *output != NULL) ++ return -1; ++ ++ while (cur < data + data_length) { ++ num++; ++ *output = must_realloc(*output, (num + 1) * sizeof(**output)); ++ (*output)[num - 1] = cur; ++ cur += strlen(cur) + 1; ++ } ++ (*output)[num] = NULL; ++ return num; ++} ++ ++/* ++ * "Parse" out argv and envp from /proc/self/cmdline and /proc/self/environ. ++ * This is necessary because we are running in a context where we don't have a ++ * main() that we can just get the arguments from. ++ */ ++static int fetchve(char ***argv, char ***envp) ++{ ++ char *cmdline = NULL, *environ = NULL; ++ size_t cmdline_size, environ_size; ++ ++ cmdline = read_file("/proc/self/cmdline", &cmdline_size); ++ if (!cmdline) ++ goto error; ++ environ = read_file("/proc/self/environ", &environ_size); ++ if (!environ) ++ goto error; ++ ++ if (parse_xargs(cmdline, cmdline_size, argv) <= 0) ++ goto error; ++ if (parse_xargs(environ, environ_size, envp) <= 0) ++ goto error; ++ ++ return 0; ++ ++error: ++ free(environ); ++ free(cmdline); ++ return -EINVAL; ++} ++ ++#define SENDFILE_MAX 0x7FFFF000 /* sendfile(2) is limited to 2GB. */ ++static int clone_binary(void) ++{ ++ int binfd, memfd, err; ++ ssize_t sent = 0; ++ ++ memfd = memfd_create(OUR_MEMFD_COMMENT, MFD_CLOEXEC | MFD_ALLOW_SEALING); ++ if (memfd < 0) ++ return -ENOTRECOVERABLE; ++ ++ binfd = open("/proc/self/exe", O_RDONLY | O_CLOEXEC); ++ if (binfd < 0) ++ goto error; ++ ++ sent = sendfile(memfd, binfd, NULL, SENDFILE_MAX); ++ close(binfd); ++ if (sent < 0) ++ goto error; ++ ++ err = fcntl(memfd, F_ADD_SEALS, OUR_MEMFD_SEALS); ++ if (err < 0) ++ goto error; ++ ++ return memfd; ++ ++error: ++ close(memfd); ++ return -EIO; ++} ++ ++int ensure_cloned_binary(void) ++{ ++ int execfd; ++ char **argv = NULL, **envp = NULL; ++ ++ /* Check that we're not self-cloned, and if we are then bail. */ ++ int cloned = is_self_cloned(); ++ if (cloned > 0 || cloned == -ENOTRECOVERABLE) ++ return cloned; ++ ++ if (fetchve(&argv, &envp) < 0) ++ return -EINVAL; ++ ++ execfd = clone_binary(); ++ if (execfd < 0) ++ return -EIO; ++ ++ fexecve(execfd, argv, envp); ++ return -ENOEXEC; ++} +diff --git a/libcontainer/nsenter/nsexec.c b/libcontainer/nsenter/nsexec.c +index 30d5d594..0019dd9a 100644 +--- a/libcontainer/nsenter/nsexec.c ++++ b/libcontainer/nsenter/nsexec.c +@@ -399,6 +399,9 @@ void nl_free(struct nlconfig_t *config) + free(config->data); + } + ++/* Defined in cloned_binary.c. */ ++int ensure_cloned_binary(void); ++ + void nsexec(void) + { + int pipenum; +@@ -414,6 +417,14 @@ void nsexec(void) + if (pipenum == -1) + return; + ++ /* ++ * We need to re-exec if we are not in a cloned binary. This is necessary ++ * to ensure that containers won't be able to access the host binary ++ * through /proc/self/exe. See CVE-2019-5736. ++ */ ++ if (ensure_cloned_binary() < 0) ++ bail("could not ensure we are a cloned binary"); ++ + /* make the process non-dumpable */ + if (prctl(PR_SET_DUMPABLE, 0, 0, 0, 0) != 0) { + bail("failed to set process as non-dumpable"); +-- +2.20.1 + diff --git a/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9.ebuild b/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9-r1.ebuild similarity index 94% rename from sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9.ebuild rename to sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9-r1.ebuild index 5fd9b610fc..6b0c2c5c6c 100644 --- a/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9.ebuild +++ b/sdk_container/src/third_party/coreos-overlay/app-emulation/runc/runc-1.0.0_rc2_p9-r1.ebuild @@ -38,6 +38,7 @@ RDEPEND=" src_prepare() { epatch "${FILESDIR}/0001-Makefile-do-not-install-dependencies-of-target.patch" epatch "${FILESDIR}/0002-${PV}-Fix-setting-selinux-label-for-mqueue-under-userns.patch" + epatch "${FILESDIR}/0001-nsenter-clone-proc-self-exe-to-avoid-exposing-host-b_1.12.patch" # Work around https://github.com/golang/go/issues/14669 # Remove after updating to go1.7 diff --git a/sdk_container/src/third_party/coreos-overlay/app-torcx/docker/docker-1.12.ebuild b/sdk_container/src/third_party/coreos-overlay/app-torcx/docker/docker-1.12.ebuild index 26bb7c73cd..13ddffa942 100644 --- a/sdk_container/src/third_party/coreos-overlay/app-torcx/docker/docker-1.12.ebuild +++ b/sdk_container/src/third_party/coreos-overlay/app-torcx/docker/docker-1.12.ebuild @@ -13,12 +13,12 @@ KEYWORDS="amd64 arm64" RDEPEND=" =app-emulation/docker-1.12.6-r8 =app-emulation/containerd-0.2.5-r3 - =app-emulation/runc-1.0.0_rc2_p9 + =app-emulation/runc-1.0.0_rc2_p9-r1 " src_install() { insinto /.torcx - newins "${FILESDIR}/${PN}-${PV}-manifest.json" manifest.json + newins "${FILESDIR}/${P}-manifest.json" manifest.json # Enable the Docker socket by default. local unitdir=/usr/lib/systemd/system diff --git a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/docker-1.12.6-r8 b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/docker-1.12.6-r8 index fd2a70abc9..58cdf11ea2 100644 --- a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/docker-1.12.6-r8 +++ b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/docker-1.12.6-r8 @@ -6,9 +6,9 @@ HOMEPAGE=https://dockerproject.org IUSE=apparmor aufs +btrfs contrib +device-mapper experimental +overlay seccomp +selinux vim-syntax zsh-completion +journald kernel_linux cros_workon_tree_ profiling +go_version_go1_7 KEYWORDS=amd64 arm64 LICENSE=Apache-2.0 -RDEPEND=>=dev-db/sqlite-3.7.9:3 device-mapper? ( >=sys-fs/lvm2-2.02.89[thin] ) seccomp? ( >=sys-libs/libseccomp-2.2.1[static-libs] ) journald? ( >=sys-apps/systemd-225 ) !app-emulation/docker-bin >=net-firewall/iptables-1.4 sys-process/procps >=dev-vcs/git-1.7 >=app-arch/xz-utils-4.9 >=sys-apps/shadow-4.4 =app-emulation/containerd-0.2.5-r3[seccomp?] =app-emulation/runc-1.0.0_rc2_p9[apparmor?,seccomp?] +RDEPEND=>=dev-db/sqlite-3.7.9:3 device-mapper? ( >=sys-fs/lvm2-2.02.89[thin] ) seccomp? ( >=sys-libs/libseccomp-2.2.1[static-libs] ) journald? ( >=sys-apps/systemd-225 ) !app-emulation/docker-bin >=net-firewall/iptables-1.4 sys-process/procps >=dev-vcs/git-1.7 >=app-arch/xz-utils-4.9 >=sys-apps/shadow-4.4 =app-emulation/containerd-0.2.5-r3[seccomp?] =app-emulation/runc-1.0.0_rc2_p9-r1[apparmor?,seccomp?] REQUIRED_USE=go_version_go1_7 RESTRICT=installsources strip SLOT=0 _eclasses_=bash-completion-r1 47a7402d95930413ce25ba8d857339bb coreos-go-depend cec6567f1c69a9b3e529a49eedaeed55 coreos-go-utils 67004337b6f831adc5f1ff107ee2f157 cros-workon 4ad6e6491a1010ad7c875302b3be18ba desktop b1d22ac8bdd4679ab79c71aca235009d eapi7-ver 756b3f27d8e46131d5cf3c51bd876446 epatch a1bf4756dba418a7238f3be0cb010c54 estack 43ddf5aaffa7a8d0482df54d25a66a1f eutils 6e6c2737b59a4b982de6fb3ecefd87f8 flag-o-matic 55aaa148741116aa54ad0d80e361818e git-r3 0d4635eeb5a96cd5315597a47eba25c9 linux-info 953c3b1c472dcadbf62098a9301327f2 ltprune 08f9e1d9ee0af8f5d9a7854efbcd8c0e multilib b2f01ad412baf81650c23fcf0975fa33 preserve-libs ef207dc62baddfddfd39a164d9797648 systemd 71fd8d2065d102753fb9e4d20eaf3e9f toolchain-funcs f164325a2cdb5b3ea39311d483988861 udev 7752f306eec7b286d00bdb47b763e7ac user 8bc2845510e2109af75e3eeac607ec81 vcs-clean 2a0f74a496fa2b1552c4f3398258b7bf -_md5_=1848ce560a3c7caf7f7ec9ac3bfee7c8 +_md5_=f7c19a1a2d89d4770384d51d45912045 diff --git a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9 b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9-r1 similarity index 96% rename from sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9 rename to sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9-r1 index 4c08b5b63a..fd5d99ddce 100644 --- a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9 +++ b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-emulation/runc-1.0.0_rc2_p9-r1 @@ -11,4 +11,4 @@ REQUIRED_USE=go_version_go1_6 SLOT=0 SRC_URI=https://github.com/opencontainers/runc/archive/50a19c6ff828c58e5dab13830bd3dacde268afe5.tar.gz -> runc-1.0.0_rc2_p9.tar.gz _eclasses_=coreos-go-depend cec6567f1c69a9b3e529a49eedaeed55 coreos-go-utils 67004337b6f831adc5f1ff107ee2f157 desktop b1d22ac8bdd4679ab79c71aca235009d epatch a1bf4756dba418a7238f3be0cb010c54 estack 43ddf5aaffa7a8d0482df54d25a66a1f eutils 6e6c2737b59a4b982de6fb3ecefd87f8 flag-o-matic 55aaa148741116aa54ad0d80e361818e ltprune 08f9e1d9ee0af8f5d9a7854efbcd8c0e multilib b2f01ad412baf81650c23fcf0975fa33 preserve-libs ef207dc62baddfddfd39a164d9797648 toolchain-funcs f164325a2cdb5b3ea39311d483988861 vcs-clean 2a0f74a496fa2b1552c4f3398258b7bf vcs-snapshot b77011b62e2053c646ad720defe6d921 -_md5_=5de83c00406eeda34385ddaad1de177f +_md5_=27e67f37add371c41c3db53b0e90a9dd diff --git a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-torcx/docker-1.12 b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-torcx/docker-1.12 index 1520cda454..68b18fdf58 100644 --- a/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-torcx/docker-1.12 +++ b/sdk_container/src/third_party/coreos-overlay/metadata/md5-cache/app-torcx/docker-1.12 @@ -3,6 +3,6 @@ DESCRIPTION=Packages to be installed in a torcx image for Docker EAPI=2 KEYWORDS=amd64 arm64 LICENSE=GPL-2 -RDEPEND==app-emulation/docker-1.12.6-r8 =app-emulation/containerd-0.2.5-r3 =app-emulation/runc-1.0.0_rc2_p9 +RDEPEND==app-emulation/docker-1.12.6-r8 =app-emulation/containerd-0.2.5-r3 =app-emulation/runc-1.0.0_rc2_p9-r1 SLOT=0 -_md5_=0173a03ae53389ae2fcf96fa36f2ccd1 +_md5_=efe1b9c718e9b537247c3d67b65380ea