From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cyril Hrubis Date: Tue, 9 Jul 2019 13:20:46 +0200 Subject: [LTP] [PATCH] syscalls/prctl07.c: New test for prctl() with PR_CAP_AMBIENT In-Reply-To: <1561356551-2970-1-git-send-email-xuyang2018.jy@cn.fujitsu.com> References: <1561356551-2970-1-git-send-email-xuyang2018.jy@cn.fujitsu.com> Message-ID: <20190709112046.GC4914@rei.lan> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it Hi! > Since Linux 4.3, PR_CAP_AMBIENT has been supported. We can read or change > the ambient capability set of the calling thread by using the following > option: PR_CAP_AMBIENT_RAISE, PR_CAP_AMBIENT_LOWER,PR_CAP_AMBIENT_IS_SET, > PR_CAP_AMBIENT_CLEAR_ALL. > > links: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5831905 > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=32ae976 > > Signed-off-by: Yang Xu > --- > configure.ac | 2 + > include/lapi/prctl.h | 8 + > include/lapi/securebits.h | 15 ++ > runtest/syscalls | 1 + > testcases/kernel/syscalls/prctl/.gitignore | 1 + > testcases/kernel/syscalls/prctl/Makefile | 2 + > testcases/kernel/syscalls/prctl/prctl07.c | 196 +++++++++++++++++++++ > 7 files changed, 225 insertions(+) > create mode 100644 include/lapi/securebits.h > create mode 100644 testcases/kernel/syscalls/prctl/prctl07.c > > diff --git a/configure.ac b/configure.ac > index f78db90ce..cf1e121bd 100644 > --- a/configure.ac > +++ b/configure.ac > @@ -33,6 +33,7 @@ AC_PROG_YACC > AC_PREFIX_DEFAULT(/opt/ltp) > > AC_CHECK_HEADERS([ \ > + cap-ng.h \ > ifaddrs.h \ > keyutils.h \ > linux/can.h \ > @@ -47,6 +48,7 @@ AC_CHECK_HEADERS([ \ > linux/module.h \ > linux/netlink.h \ > linux/seccomp.h \ > + linux/securebits.h \ > linux/userfaultfd.h \ > mm.h \ > netinet/sctp.h \ > diff --git a/include/lapi/prctl.h b/include/lapi/prctl.h > index 54b3da20f..8ee492259 100644 > --- a/include/lapi/prctl.h > +++ b/include/lapi/prctl.h > @@ -29,4 +29,12 @@ > # define PR_GET_NO_NEW_PRIVS 39 > #endif > > +#ifndef PR_CAP_AMBIENT > +# define PR_CAP_AMBIENT 47 > +# define PR_CAP_AMBIENT_IS_SET 1 > +# define PR_CAP_AMBIENT_RAISE 2 > +# define PR_CAP_AMBIENT_LOWER 3 > +# define PR_CAP_AMBIENT_CLEAR_ALL 4 > +#endif > + > #endif /* LAPI_PRCTL_H__ */ > diff --git a/include/lapi/securebits.h b/include/lapi/securebits.h > new file mode 100644 > index 000000000..9c9216e13 > --- /dev/null > +++ b/include/lapi/securebits.h > @@ -0,0 +1,15 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. > + * Author: Yang Xu > + */ > +#ifndef LAPI_SECUREBITS_H > +#define LAPI_SECUREBITS_H > + > +# ifdef HAVE_LINUX_SECUREBITS_H > +# include > +# endif /* HAVE_LINUX_SECUREBITS_H*/ > +# ifndef SECBIT_NO_CAP_AMBIENT_RAISE > +# define SECBIT_NO_CAP_AMBIENT_RAISE 6 > +# endif > +#endif /* LAPI_SECUREBITS_H */ > diff --git a/runtest/syscalls b/runtest/syscalls > index 742739c2c..4a03c5818 100644 > --- a/runtest/syscalls > +++ b/runtest/syscalls > @@ -868,6 +868,7 @@ prctl03 prctl03 > prctl04 prctl04 > prctl05 prctl05 > prctl06 prctl06 > +prctl07 prctl07 > > pread01 pread01 > pread01_64 pread01_64 > diff --git a/testcases/kernel/syscalls/prctl/.gitignore b/testcases/kernel/syscalls/prctl/.gitignore > index f52f6f665..b913d1798 100644 > --- a/testcases/kernel/syscalls/prctl/.gitignore > +++ b/testcases/kernel/syscalls/prctl/.gitignore > @@ -4,3 +4,4 @@ > /prctl04 > /prctl05 > /prctl06 > +/prctl07 > diff --git a/testcases/kernel/syscalls/prctl/Makefile b/testcases/kernel/syscalls/prctl/Makefile > index bd617d806..6bb839a7d 100644 > --- a/testcases/kernel/syscalls/prctl/Makefile > +++ b/testcases/kernel/syscalls/prctl/Makefile > @@ -20,4 +20,6 @@ top_srcdir ?= ../../../.. > > include $(top_srcdir)/include/mk/testcases.mk > > +LDLIBS += -lcap-ng This will break the compilation without the cap-ng library, we have to check for the presence in the configure script. See for example m4/ltp-cap.m4 where we define a variable that is then used Makefiles e.g. in syscalls/pivot_root/Makefile. Also LTP depends on libcap already, so maybe it would be better to use the libcap instead of cap-ng in order to keep the number of libraries we depend on as small as possible. > include $(top_srcdir)/include/mk/generic_leaf_target.mk > diff --git a/testcases/kernel/syscalls/prctl/prctl07.c b/testcases/kernel/syscalls/prctl/prctl07.c > new file mode 100644 > index 000000000..a7c8596a3 > --- /dev/null > +++ b/testcases/kernel/syscalls/prctl/prctl07.c > @@ -0,0 +1,196 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. > + * Author: Yang Xu > + * > + * Test the PR_CAP_AMBIENT of prctl(2). > + * Reads or changes the ambient capability set of the calling thread, > + * according to the value of arg2, which must be one of the following: > + * 1)PR_CAP_AMBIENT_RAISE: > + * The capability specified in arg3 is added to the ambient set. > + * The specified capability must already be present in both pE and pI. > + * If we set SECBIT_NO_CAP_AMBIENT_RAISE bit, raise option will be rejected > + * and retrun EPERM. We also raise a CAP twice. > + * 2)PR_CAP_AMBIENT_LOWER: > + * The capability specified in arg3 is removed from the ambient set. > + * Even though this cap is not in set, it also should return 0. > + * 3)PR_CAP_AMBIENT_IS_SET: > + * Returns 1 if the capability in arg3 is in the ambient set and 0 if it > + * is not. > + * 4)PR_CAP_AMBIENT_CLEAR_ALL: > + * All capabilities will be removed from the ambient set. This operation > + * requires setting arg3 to zero. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include "config.h" > +#if HAVE_CAP_NG_H > +#include > +#endif > +#include "lapi/syscalls.h" > +#include "lapi/prctl.h" > +#include "lapi/securebits.h" > +#include "tst_test.h" > + > +#if HAVE_CAP_NG_H > +static void check_proc_capamb(char *message, char *path, int flag) > +{ > + unsigned int cap_num; > + char CapAmb[20]; > + > + SAFE_FILE_LINES_SCANF(path, "CapAmb:%s", CapAmb); > + cap_num = atoi(CapAmb); > + if (flag == 2) { > + if (cap_num == 0) > + tst_res(TPASS, > + "%s, %s CapAmb has been clear as %d", > + message, path, cap_num); > + else > + tst_res(TFAIL, > + "%s, %s CapAmb has been clear expect 0, got %d", > + message, path, cap_num); > + return; > + } > + > + if (cap_num == 400) > + tst_res(flag ? TPASS : TFAIL, > + "%s, CapAmb in %s has CAP_NET_BIND_SERVICE", > + message, path); > + else > + tst_res(flag ? TFAIL : TPASS, > + "%s, CapAmb in %s doesn't have CAP_NET_BIND_SERVICE", > + message, path); > +} > + > +static void check_cap_raise(unsigned int cap, char *message, int fail_flag) > +{ > + TEST(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, cap, 0, 0, 0)); > + switch (fail_flag) { > + case 0: > + if (TST_RET == 0) > + tst_res(TPASS, "PR_CAP_AMBIENT_RAISE %s succeeded", message); > + else > + tst_res(TFAIL, "PR_CAP_AMBIENT_RAISE %s failed unexpectedly", > + message); > + break; > + case 1: > + if (TST_RET == 0) > + tst_res(TFAIL, > + "PR_CAP_AMBIENT_RAISE succeeded unexpectedly %s", > + message); > + else if (TST_ERR == EPERM) > + tst_res(TPASS, > + "PR_CAP_AMBIENT_RAISE failed with EPERM %s", message); > + else > + tst_res(TFAIL | TERRNO, > + "PR_CAP_AMBIENT_RAISE failed %s", message); > + break; > + } > +} > + > +static void check_cap_is_set(unsigned int cap, char *message, int val) > +{ > + TEST(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_IS_SET, cap, 0, 0, 0)); > + if (TST_RET == 1) > + tst_res(val ? TPASS : TFAIL, > + "PR_CAP_AMBIENT_IS_SET %s in AmbientCap", message); > + else if (TST_RET == 0) > + tst_res(val ? TFAIL : TPASS, > + "PR_CAP_AMBIENT_IS_SET %s not in AmbientCap", message); > + else > + tst_res(TFAIL | TERRNO, "PR_CAP_AMBIENT_IS_SET failed"); > +} > + > +static void check_cap_lower(unsigned int cap, char *message) > +{ > + TEST(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_LOWER, cap, 0, 0, 0)); > + if (TST_RET == -1) > + tst_res(TFAIL | TERRNO, > + "PR_CAP_AMBIENT_LOWER %s failed", message); > + else > + tst_res(TPASS, "PR_CAP_AMBIENT_LOWER %s succeeded", message); > +} > +#endif > + > +static void verify_prctl(void) > +{ > +#if HAVE_CAP_NG_H > + pid_t pid; > + char path[50]; > + > + pid = getpid(); > + sprintf(path, "/proc/%d/status", pid); ^ Why not just /proc/self/status ? > + check_proc_capamb("At the beginning", path, 0); > + > + capng_get_caps_process(); > + capng_update(CAPNG_DROP, CAPNG_INHERITABLE, CAP_NET_BIND_SERVICE); > + if (capng_apply(CAPNG_SELECT_CAPS) != 0) > + return; > + check_cap_raise(CAP_NET_BIND_SERVICE, "on non-inheritable cap", 1); > + > + capng_update(CAPNG_ADD, CAPNG_INHERITABLE, CAP_NET_RAW); > + capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_NET_RAW); > + capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_NET_RAW); > + if (capng_apply(CAPNG_SELECT_CAPS) != 0) > + return; > + check_cap_raise(CAP_NET_RAW, "on non-permitted cap", 1); > + > + capng_update(CAPNG_ADD, CAPNG_INHERITABLE, CAP_NET_BIND_SERVICE); > + if (capng_apply(CAPNG_SELECT_CAPS) != 0) > + return; > + prctl(PR_SET_SECUREBITS, SECBIT_NO_CAP_AMBIENT_RAISE); > + check_cap_raise(CAP_NET_BIND_SERVICE, "because of NO_RAISE_SECBIT set", 1); > + prctl(PR_SET_SECUREBITS, 0); > + > + check_cap_raise(CAP_NET_BIND_SERVICE, "CAP_NET_BIND_SERVICE", 0); > + /*Even this cap has been in ambient set, raise succeeds and return 0*/ > + check_cap_raise(CAP_NET_BIND_SERVICE, "CAP_NET_BIND_SERIVCE twice", 0); > + > + check_proc_capamb("After PR_CAP_AMBIENT_RAISE", path, 1); > + > + check_cap_is_set(CAP_NET_BIND_SERVICE, "CAP_NET_BIND_SERVICE was", 1); > + check_cap_is_set(CAP_NET_RAW, "CAP_NET_RAW was", 0); > + /*move a cap what was not in ambient set, it also return 0*/ > + check_cap_lower(CAP_NET_RAW, "CAP_NET_RAW(it wasn't in ambient set)"); > + check_cap_lower(CAP_NET_BIND_SERVICE, "CAP_NET_BIND_SERVICE(it was in ambient set)"); > + check_proc_capamb("After PR_CAP_AMBIENT_LORWER", path, 0); > + > + prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, CAP_NET_BIND_SERVICE, 0, 0, 0); > + tst_res(TINFO, "raise cap for clear"); > + TEST(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_CLEAR_ALL, 0, 0, 0, 0)); > + if (TST_RET == 0) > + tst_res(TPASS, "PR_CAP_AMBIENT_CLEAR ALL succeeded"); > + else > + tst_res(TFAIL | TERRNO, "PR_AMBIENT_CLEAR_ALL failed"); > + > + check_proc_capamb("After PR_CAP_AMBIENT_CLEAN_ALL", path, 2); > +#else > + tst_res(TCONF, "system doesn't have cap-ng library"); > +#endif > +} > + > +static void setup(void) > +{ > + TEST(prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_CLEAR_ALL, 0, 0, 0, 0)); > + if (TST_RET == 0) { > + tst_res(TINFO, "kernel supports PR_CAP_AMBIENT"); > + return; > + } > + > + if (TST_ERR == EINVAL) > + tst_brk(TCONF, "kernel doesn't support PR_CAP_AMBIENT"); > + > + tst_brk(TBROK | TERRNO, > + "current environment doesn't permit PR_CAP_AMBIENT"); > +} > + > +static struct tst_test test = { > + .setup = setup, > + .test_all = verify_prctl, > + .needs_root = 1, > +}; > -- > 2.18.1 > > > > > -- > Mailing list info: https://lists.linux.it/listinfo/ltp -- Cyril Hrubis chrubis@suse.cz