| Message ID | 1557404498-3879-1-git-send-email-xuyang2018.jy@cn.fujitsu.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | syscalls/prctl06.c: New test for prctl() with PR_{SET, GET}_NO_NEW_PRIVS | expand |
Hi Ping.:-) > Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com> > --- > include/lapi/prctl.h | 5 + > runtest/syscalls | 1 + > testcases/kernel/syscalls/prctl/.gitignore | 1 + > testcases/kernel/syscalls/prctl/Makefile | 2 + > testcases/kernel/syscalls/prctl/prctl06.c | 117 ++++++++++++++++++ > .../kernel/syscalls/prctl/prctl06_execve.c | 46 +++++++ > 6 files changed, 172 insertions(+) > create mode 100644 testcases/kernel/syscalls/prctl/prctl06.c > create mode 100644 testcases/kernel/syscalls/prctl/prctl06_execve.c > > diff --git a/include/lapi/prctl.h b/include/lapi/prctl.h > index 91da9c2d6..663ce19e9 100644 > --- a/include/lapi/prctl.h > +++ b/include/lapi/prctl.h > @@ -24,4 +24,9 @@ > # define PR_SET_SECCOMP 22 > #endif > > +#ifndef PR_SET_NO_NEW_PRIVS > +# define PR_SET_NO_NEW_PRIVS 38 > +# define PR_GET_NO_NEW_PRIVS 39 > +#endif > + > #endif /* LAPI_PRCTL_H__ */ > diff --git a/runtest/syscalls b/runtest/syscalls > index 950615bef..a43bf5e4d 100644 > --- a/runtest/syscalls > +++ b/runtest/syscalls > @@ -865,6 +865,7 @@ prctl02 prctl02 > prctl03 prctl03 > prctl04 prctl04 > prctl05 prctl05 > +prctl06 prctl06 > > pread01 pread01 > pread01_64 pread01_64 > diff --git a/testcases/kernel/syscalls/prctl/.gitignore b/testcases/kernel/syscalls/prctl/.gitignore > index 9ecaf9854..f52f6f665 100644 > --- a/testcases/kernel/syscalls/prctl/.gitignore > +++ b/testcases/kernel/syscalls/prctl/.gitignore > @@ -3,3 +3,4 @@ > /prctl03 > /prctl04 > /prctl05 > +/prctl06 > diff --git a/testcases/kernel/syscalls/prctl/Makefile b/testcases/kernel/syscalls/prctl/Makefile > index bd617d806..99a9d42e7 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 += $(CAP_LIBS) > + > include $(top_srcdir)/include/mk/generic_leaf_target.mk > diff --git a/testcases/kernel/syscalls/prctl/prctl06.c b/testcases/kernel/syscalls/prctl/prctl06.c > new file mode 100644 > index 000000000..ba5c2bcfb > --- /dev/null > +++ b/testcases/kernel/syscalls/prctl/prctl06.c > @@ -0,0 +1,117 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. > + * Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com> > + * > + * Test PR_GET_NO_NEW_PRIVS and PR_SET_NO_NEW_PRIVS of prctl(2). > + * > + * 1)Return (as the function result) the value of the no_new_privs bit > + * for the calling thread. A value of 0 indicates the regular execve(2) > + * behavior. A value of 1 indicates execve(2) will operate in the > + * privilege-restricting mode. > + * 2)With no_new_privs set to 1, execve(2) promises not to grant privileges > + * to do anything that could not have been done without the execve(2) > + * call(for example, rendering the set-user-ID and set-group-ID mode bits) > + * 3)The setting of this bit is inherited by children created by fork(2) and > + * clone(2), and preserved across execve(2). > + */ > + > +#include <errno.h> > +#include <stdio.h> > +#include <stdlib.h> > +#include <sys/prctl.h> > +#include <pwd.h> > +#include <sys/types.h> > +#include <unistd.h> > +#include <sys/capability.h> > +#include <lapi/prctl.h> > +#include "tst_test.h" > + > +#define IPC_ENV_VAR "LTP_IPC_PATH" > + > +static void check_no_new_privs(int val) > +{ > + TEST(prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0)); > + if (TST_RET == val) > + tst_res(TPASS, > + "prctl(PR_GET_NO_NEW_PRIVS) got %d " > + "when no_new_privs was %d", val, val); > + else > + tst_res(TFAIL | TTERRNO, > + "prctl(PR_GET_NO_NEW_PRIVS) expected %d got %ld", > + val, TST_RET); > + return; > +} > + > +static void do_prctl(void) > +{ > + char path[4096]; > + char ipc_env_var[1024]; > + char *const argv[] = {"prctl06_execve", "parent process", NULL}; > + char *const childargv[] = {"prctl06_execve", "child process", NULL}; > + char *const envp[] = {"LTP_TEST_ENV_VAR=test", ipc_env_var, NULL }; > + cap_t caps = cap_init(); > + cap_value_t capList = CAP_SETGID; > + unsigned int num_caps = 1; > + int childpid; > + > + cap_set_flag(caps, CAP_EFFECTIVE, num_caps, &capList, CAP_SET); > + cap_set_flag(caps, CAP_INHERITABLE, num_caps, &capList, CAP_SET); > + cap_set_flag(caps, CAP_PERMITTED, num_caps, &capList, CAP_SET); > + > + if (cap_set_proc(caps)) > + tst_brk(TFAIL | TERRNO, > + "cap_set_flag(CAP_SETGID) failed"); > + tst_res(TINFO, "cap_set_flag(CAP_SETGID) succeeded"); > + > + check_no_new_privs(0); > + > + TEST(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); > + if (TST_RET == -1) { > + tst_res(TFAIL | TTERRNO, "prctl(PR_SET_NO_NEW_PRIVS) failed"); > + return; > + } > + tst_res(TPASS, "prctl(PR_SET_NO_NEW_PRIVS) succeeded"); > + > + check_no_new_privs(1); > + > + if (tst_get_path("prctl06_execve", path, sizeof(path))) > + tst_brk(TCONF, "Couldn't find prctl_execve in $PATH"); > + > + sprintf(ipc_env_var, IPC_ENV_VAR "=%s", getenv(IPC_ENV_VAR)); > + childpid = SAFE_FORK(); > + if (childpid == 0) { > + check_no_new_privs(1); > + execve(path, childargv, envp); > + tst_brk(TFAIL | TERRNO, > + "child process failed to execute prctl_execve"); > + > + } else { > + tst_reap_children(); > + execve(path, argv, envp); > + tst_brk(TFAIL | TERRNO, > + "parent process failed to execute prctl_execve"); > + } > + cap_free(caps); > + return; > +} > + > +static void verify_prctl(void) > +{ > + int pid; > + > + pid = SAFE_FORK(); > + if (pid == 0) { > + do_prctl(); > + exit(0); > + } > + tst_reap_children(); > + return; > +} > + > +static struct tst_test test = { > + .test_all = verify_prctl, > + .forks_child = 1, > + .needs_root = 1, > + .child_needs_reinit = 1, > +}; > diff --git a/testcases/kernel/syscalls/prctl/prctl06_execve.c b/testcases/kernel/syscalls/prctl/prctl06_execve.c > new file mode 100644 > index 000000000..84c28551c > --- /dev/null > +++ b/testcases/kernel/syscalls/prctl/prctl06_execve.c > @@ -0,0 +1,46 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. > + * Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com> > + * > + * dummy program which is used by prctl06 testcase > + */ > +#define TST_NO_DEFAULT_MAIN > +#include <stdlib.h> > +#include <sys/types.h> > +#include <unistd.h> > +#include <errno.h> > +#include <pwd.h> > +#include "tst_test.h" > + > +int main(int argc, char **argv) > +{ > + struct passwd *pw; > + uid_t nobody_uid; > + gid_t nobody_gid; > + > + tst_reinit(); > + if (argc != 2) > + tst_brk(TFAIL, "argc is %d, expected 2", argc); > + > + pw = SAFE_GETPWNAM("nobody"); > + nobody_uid = pw->pw_uid; > + nobody_gid = pw->pw_gid; > + /*positive check*/ > + TEST(setgid(nobody_gid)); > + if (TST_RET == -1) > + tst_res(TFAIL | TTERRNO, > + "%s setgid(%d) isn't permmit", argv[1], nobody_gid); > + else > + tst_res(TPASS, "%s setgid(%d) succeed expectedly", > + argv[1], nobody_gid); > + /*negative check*/ > + TEST(setuid(nobody_uid)); > + if (TST_RET == -1) > + tst_res(TPASS | TTERRNO, > + "%s setuid(%d) isn't permmit", argv[1], nobody_uid); > + else > + tst_res(TFAIL, " %s setuid(%d) succeed unexpectedly", > + argv[1], nobody_gid); > + return 0; > +}
Hi! > +#define IPC_ENV_VAR "LTP_IPC_PATH" > + > +static void check_no_new_privs(int val) > +{ > + TEST(prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0)); > + if (TST_RET == val) > + tst_res(TPASS, > + "prctl(PR_GET_NO_NEW_PRIVS) got %d " > + "when no_new_privs was %d", val, val); > + else > + tst_res(TFAIL | TTERRNO, > + "prctl(PR_GET_NO_NEW_PRIVS) expected %d got %ld", > + val, TST_RET); > + return; This return is useless. > +} > + > +static void do_prctl(void) > +{ > + char path[4096]; > + char ipc_env_var[1024]; > + char *const argv[] = {"prctl06_execve", "parent process", NULL}; > + char *const childargv[] = {"prctl06_execve", "child process", NULL}; > + char *const envp[] = {"LTP_TEST_ENV_VAR=test", ipc_env_var, NULL }; > + cap_t caps = cap_init(); > + cap_value_t capList = CAP_SETGID; > + unsigned int num_caps = 1; > + int childpid; > + > + cap_set_flag(caps, CAP_EFFECTIVE, num_caps, &capList, CAP_SET); > + cap_set_flag(caps, CAP_INHERITABLE, num_caps, &capList, CAP_SET); > + cap_set_flag(caps, CAP_PERMITTED, num_caps, &capList, CAP_SET); > + > + if (cap_set_proc(caps)) > + tst_brk(TFAIL | TERRNO, > + "cap_set_flag(CAP_SETGID) failed"); You cannot use tst_brk with TFAIL, the best you can do here is to use tst_ret(TFAIL ... ) then return; as you do below. > + tst_res(TINFO, "cap_set_flag(CAP_SETGID) succeeded"); > + > + check_no_new_privs(0); > + > + TEST(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); > + if (TST_RET == -1) { > + tst_res(TFAIL | TTERRNO, "prctl(PR_SET_NO_NEW_PRIVS) failed"); > + return; > + } > + tst_res(TPASS, "prctl(PR_SET_NO_NEW_PRIVS) succeeded"); > + > + check_no_new_privs(1); > + > + if (tst_get_path("prctl06_execve", path, sizeof(path))) > + tst_brk(TCONF, "Couldn't find prctl_execve in $PATH"); If the path to the binary is in $PATH you don't have to execute the binary by an absolute path, passing it's name to execve() should suffice. > + sprintf(ipc_env_var, IPC_ENV_VAR "=%s", getenv(IPC_ENV_VAR)); > + childpid = SAFE_FORK(); > + if (childpid == 0) { > + check_no_new_privs(1); Maybe we can pass a "child" string here and "parent" string in the cases above so that we can print if the check was done in child/parent in the tst_res() inside of this function. > + execve(path, childargv, envp); > + tst_brk(TFAIL | TERRNO, > + "child process failed to execute prctl_execve"); > + > + } else { > + tst_reap_children(); > + execve(path, argv, envp); > + tst_brk(TFAIL | TERRNO, > + "parent process failed to execute prctl_execve"); > + } > + cap_free(caps); > + return; > +} > + > +static void verify_prctl(void) > +{ > + int pid; > + > + pid = SAFE_FORK(); > + if (pid == 0) { > + do_prctl(); > + exit(0); > + } > + tst_reap_children(); > + return; > +} > + > +static struct tst_test test = { > + .test_all = verify_prctl, > + .forks_child = 1, > + .needs_root = 1, > + .child_needs_reinit = 1, > +}; > diff --git a/testcases/kernel/syscalls/prctl/prctl06_execve.c b/testcases/kernel/syscalls/prctl/prctl06_execve.c > new file mode 100644 > index 000000000..84c28551c > --- /dev/null > +++ b/testcases/kernel/syscalls/prctl/prctl06_execve.c > @@ -0,0 +1,46 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. > + * Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com> > + * > + * dummy program which is used by prctl06 testcase > + */ > +#define TST_NO_DEFAULT_MAIN > +#include <stdlib.h> > +#include <sys/types.h> > +#include <unistd.h> > +#include <errno.h> > +#include <pwd.h> > +#include "tst_test.h" > + > +int main(int argc, char **argv) > +{ > + struct passwd *pw; > + uid_t nobody_uid; > + gid_t nobody_gid; > + > + tst_reinit(); > + if (argc != 2) > + tst_brk(TFAIL, "argc is %d, expected 2", argc); > + > + pw = SAFE_GETPWNAM("nobody"); > + nobody_uid = pw->pw_uid; > + nobody_gid = pw->pw_gid; > + /*positive check*/ > + TEST(setgid(nobody_gid)); > + if (TST_RET == -1) > + tst_res(TFAIL | TTERRNO, > + "%s setgid(%d) isn't permmit", argv[1], nobody_gid); > + else > + tst_res(TPASS, "%s setgid(%d) succeed expectedly", > + argv[1], nobody_gid); > + /*negative check*/ > + TEST(setuid(nobody_uid)); > + if (TST_RET == -1) > + tst_res(TPASS | TTERRNO, > + "%s setuid(%d) isn't permmit", argv[1], nobody_uid); > + else > + tst_res(TFAIL, " %s setuid(%d) succeed unexpectedly", > + argv[1], nobody_gid); > + return 0; > +} I do not think that this is actually testing the prctl in question. Here we actually check that capabilities were inherited over fork() + exec(). As far as I understand the PR_SET_NO_NEW_PRIVS it has been designed expecially to avoid misuse of capabilities associated with a particular file. So the check would have to do: 1. copy the prctl06_execve binary to a $PWD 2. chmod it with S_ISUID, S_ISGID 3. the prct06_execve would be executed under user/group nobody 4. the prct06_execve itself would check if it gained root priviledges And we can do the same for capablities as well. I guess that we would have to format a device and mount it with support for capabilities for the test, since as far as I can tell you cannot usually do neither of set-usr-id or add capabilites to files in /tmp/.
Hi Cyril Sorry for the late reply. > Hi! >> +#define IPC_ENV_VAR "LTP_IPC_PATH" >> + >> +static void check_no_new_privs(int val) >> +{ >> + TEST(prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0)); >> + if (TST_RET == val) >> + tst_res(TPASS, >> + "prctl(PR_GET_NO_NEW_PRIVS) got %d " >> + "when no_new_privs was %d", val, val); >> + else >> + tst_res(TFAIL | TTERRNO, >> + "prctl(PR_GET_NO_NEW_PRIVS) expected %d got %ld", >> + val, TST_RET); >> + return; > This return is useless. OK. I will remove it and add check for /proc/[pid]/status for NoNewPrivs. >> +} >> + >> +static void do_prctl(void) >> +{ >> + char path[4096]; >> + char ipc_env_var[1024]; >> + char *const argv[] = {"prctl06_execve", "parent process", NULL}; >> + char *const childargv[] = {"prctl06_execve", "child process", NULL}; >> + char *const envp[] = {"LTP_TEST_ENV_VAR=test", ipc_env_var, NULL }; >> + cap_t caps = cap_init(); >> + cap_value_t capList = CAP_SETGID; >> + unsigned int num_caps = 1; >> + int childpid; >> + >> + cap_set_flag(caps, CAP_EFFECTIVE, num_caps,&capList, CAP_SET); >> + cap_set_flag(caps, CAP_INHERITABLE, num_caps,&capList, CAP_SET); >> + cap_set_flag(caps, CAP_PERMITTED, num_caps,&capList, CAP_SET); >> + >> + if (cap_set_proc(caps)) >> + tst_brk(TFAIL | TERRNO, >> + "cap_set_flag(CAP_SETGID) failed"); > You cannot use tst_brk with TFAIL, the best you can do here is to use > tst_ret(TFAIL ... ) then return; as you do below. > I got it. >> + tst_res(TINFO, "cap_set_flag(CAP_SETGID) succeeded"); >> + >> + check_no_new_privs(0); >> + >> + TEST(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); >> + if (TST_RET == -1) { >> + tst_res(TFAIL | TTERRNO, "prctl(PR_SET_NO_NEW_PRIVS) failed"); >> + return; >> + } >> + tst_res(TPASS, "prctl(PR_SET_NO_NEW_PRIVS) succeeded"); >> + >> + check_no_new_privs(1); >> + >> + if (tst_get_path("prctl06_execve", path, sizeof(path))) >> + tst_brk(TCONF, "Couldn't find prctl_execve in $PATH"); > If the path to the binary is in $PATH you don't have to execute the > binary by an absolute path, passing it's name to execve() should > suffice. > It sounds reasonable. I will pass binary_name directly. >> + sprintf(ipc_env_var, IPC_ENV_VAR "=%s", getenv(IPC_ENV_VAR)); >> + childpid = SAFE_FORK(); >> + if (childpid == 0) { >> + check_no_new_privs(1); > Maybe we can pass a "child" string here and "parent" > string in the cases above so that we can print if the > check was done in child/parent in the tst_res() inside > of this function. > Ok. Pass a "child" or "parent" string can make it more clear for user. >> + execve(path, childargv, envp); >> + tst_brk(TFAIL | TERRNO, >> + "child process failed to execute prctl_execve"); >> + >> + } else { >> + tst_reap_children(); >> + execve(path, argv, envp); >> + tst_brk(TFAIL | TERRNO, >> + "parent process failed to execute prctl_execve"); >> + } >> + cap_free(caps); >> + return; >> +} >> + >> +static void verify_prctl(void) >> +{ >> + int pid; >> + >> + pid = SAFE_FORK(); >> + if (pid == 0) { >> + do_prctl(); >> + exit(0); >> + } >> + tst_reap_children(); >> + return; >> +} >> + >> +static struct tst_test test = { >> + .test_all = verify_prctl, >> + .forks_child = 1, >> + .needs_root = 1, >> + .child_needs_reinit = 1, >> +}; >> diff --git a/testcases/kernel/syscalls/prctl/prctl06_execve.c b/testcases/kernel/syscalls/prctl/prctl06_execve.c >> new file mode 100644 >> index 000000000..84c28551c >> --- /dev/null >> +++ b/testcases/kernel/syscalls/prctl/prctl06_execve.c >> @@ -0,0 +1,46 @@ >> +// SPDX-License-Identifier: GPL-2.0-or-later >> +/* >> + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. >> + * Author: Yang Xu<xuyang2018.jy@cn.fujitsu.com> >> + * >> + * dummy program which is used by prctl06 testcase >> + */ >> +#define TST_NO_DEFAULT_MAIN >> +#include<stdlib.h> >> +#include<sys/types.h> >> +#include<unistd.h> >> +#include<errno.h> >> +#include<pwd.h> >> +#include "tst_test.h" >> + >> +int main(int argc, char **argv) >> +{ >> + struct passwd *pw; >> + uid_t nobody_uid; >> + gid_t nobody_gid; >> + >> + tst_reinit(); >> + if (argc != 2) >> + tst_brk(TFAIL, "argc is %d, expected 2", argc); >> + >> + pw = SAFE_GETPWNAM("nobody"); >> + nobody_uid = pw->pw_uid; >> + nobody_gid = pw->pw_gid; >> + /*positive check*/ >> + TEST(setgid(nobody_gid)); >> + if (TST_RET == -1) >> + tst_res(TFAIL | TTERRNO, >> + "%s setgid(%d) isn't permmit", argv[1], nobody_gid); >> + else >> + tst_res(TPASS, "%s setgid(%d) succeed expectedly", >> + argv[1], nobody_gid); >> + /*negative check*/ >> + TEST(setuid(nobody_uid)); >> + if (TST_RET == -1) >> + tst_res(TPASS | TTERRNO, >> + "%s setuid(%d) isn't permmit", argv[1], nobody_uid); >> + else >> + tst_res(TFAIL, " %s setuid(%d) succeed unexpectedly", >> + argv[1], nobody_gid); >> + return 0; >> +} > I do not think that this is actually testing the prctl in question. Here > we actually check that capabilities were inherited over fork() + exec(). > > As far as I understand the PR_SET_NO_NEW_PRIVS it has been designed > expecially to avoid misuse of capabilities associated with a particular > file. > > So the check would have to do: > > 1. copy the prctl06_execve binary to a $PWD > 2. chmod it with S_ISUID, S_ISGID > 3. the prct06_execve would be executed under user/group nobody > 4. the prct06_execve itself would check if it gained root priviledges > I have seen documention about PR_SET_NO_NEW_PRIVS. I think your way is right. But I have reset this capabilities and only keep CAP_SETGID, so when I set no_new_privs to 1, prctl06_execve inherits CAP_SETGID but not gain CAP_SETUID. > And we can do the same for capablities as well. > > I guess that we would have to format a device and mount it with support > for capabilities for the test, since as far as I can tell you cannot > usually do neither of set-usr-id or add capabilites to files in /tmp/. Yes. In /tmp, these make no sense. I will follow by your advise. Thanks Yang Xu
Hi! Can you pretty please resend the prctl06 v2 patch? I can see it in the patchwork at http://patchwork.ozlabs.org/patch/1118628/ but that email haven't made it to my mailbox.
> Hi! > Can you pretty please resend the prctl06 v2 patch? > > I can see it in the patchwork at > http://patchwork.ozlabs.org/patch/1118628/ > but that email haven't made it to my mailbox. > Hi cyril I have resent it again. ps:I sent it but email date is 2019/07/06 6:48 (my virtual machine date is incorrect I don't notice it ) Thanks Yang Xu
diff --git a/include/lapi/prctl.h b/include/lapi/prctl.h index 91da9c2d6..663ce19e9 100644 --- a/include/lapi/prctl.h +++ b/include/lapi/prctl.h @@ -24,4 +24,9 @@ # define PR_SET_SECCOMP 22 #endif +#ifndef PR_SET_NO_NEW_PRIVS +# define PR_SET_NO_NEW_PRIVS 38 +# define PR_GET_NO_NEW_PRIVS 39 +#endif + #endif /* LAPI_PRCTL_H__ */ diff --git a/runtest/syscalls b/runtest/syscalls index 950615bef..a43bf5e4d 100644 --- a/runtest/syscalls +++ b/runtest/syscalls @@ -865,6 +865,7 @@ prctl02 prctl02 prctl03 prctl03 prctl04 prctl04 prctl05 prctl05 +prctl06 prctl06 pread01 pread01 pread01_64 pread01_64 diff --git a/testcases/kernel/syscalls/prctl/.gitignore b/testcases/kernel/syscalls/prctl/.gitignore index 9ecaf9854..f52f6f665 100644 --- a/testcases/kernel/syscalls/prctl/.gitignore +++ b/testcases/kernel/syscalls/prctl/.gitignore @@ -3,3 +3,4 @@ /prctl03 /prctl04 /prctl05 +/prctl06 diff --git a/testcases/kernel/syscalls/prctl/Makefile b/testcases/kernel/syscalls/prctl/Makefile index bd617d806..99a9d42e7 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 += $(CAP_LIBS) + include $(top_srcdir)/include/mk/generic_leaf_target.mk diff --git a/testcases/kernel/syscalls/prctl/prctl06.c b/testcases/kernel/syscalls/prctl/prctl06.c new file mode 100644 index 000000000..ba5c2bcfb --- /dev/null +++ b/testcases/kernel/syscalls/prctl/prctl06.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. + * Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com> + * + * Test PR_GET_NO_NEW_PRIVS and PR_SET_NO_NEW_PRIVS of prctl(2). + * + * 1)Return (as the function result) the value of the no_new_privs bit + * for the calling thread. A value of 0 indicates the regular execve(2) + * behavior. A value of 1 indicates execve(2) will operate in the + * privilege-restricting mode. + * 2)With no_new_privs set to 1, execve(2) promises not to grant privileges + * to do anything that could not have been done without the execve(2) + * call(for example, rendering the set-user-ID and set-group-ID mode bits) + * 3)The setting of this bit is inherited by children created by fork(2) and + * clone(2), and preserved across execve(2). + */ + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/prctl.h> +#include <pwd.h> +#include <sys/types.h> +#include <unistd.h> +#include <sys/capability.h> +#include <lapi/prctl.h> +#include "tst_test.h" + +#define IPC_ENV_VAR "LTP_IPC_PATH" + +static void check_no_new_privs(int val) +{ + TEST(prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0)); + if (TST_RET == val) + tst_res(TPASS, + "prctl(PR_GET_NO_NEW_PRIVS) got %d " + "when no_new_privs was %d", val, val); + else + tst_res(TFAIL | TTERRNO, + "prctl(PR_GET_NO_NEW_PRIVS) expected %d got %ld", + val, TST_RET); + return; +} + +static void do_prctl(void) +{ + char path[4096]; + char ipc_env_var[1024]; + char *const argv[] = {"prctl06_execve", "parent process", NULL}; + char *const childargv[] = {"prctl06_execve", "child process", NULL}; + char *const envp[] = {"LTP_TEST_ENV_VAR=test", ipc_env_var, NULL }; + cap_t caps = cap_init(); + cap_value_t capList = CAP_SETGID; + unsigned int num_caps = 1; + int childpid; + + cap_set_flag(caps, CAP_EFFECTIVE, num_caps, &capList, CAP_SET); + cap_set_flag(caps, CAP_INHERITABLE, num_caps, &capList, CAP_SET); + cap_set_flag(caps, CAP_PERMITTED, num_caps, &capList, CAP_SET); + + if (cap_set_proc(caps)) + tst_brk(TFAIL | TERRNO, + "cap_set_flag(CAP_SETGID) failed"); + tst_res(TINFO, "cap_set_flag(CAP_SETGID) succeeded"); + + check_no_new_privs(0); + + TEST(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)); + if (TST_RET == -1) { + tst_res(TFAIL | TTERRNO, "prctl(PR_SET_NO_NEW_PRIVS) failed"); + return; + } + tst_res(TPASS, "prctl(PR_SET_NO_NEW_PRIVS) succeeded"); + + check_no_new_privs(1); + + if (tst_get_path("prctl06_execve", path, sizeof(path))) + tst_brk(TCONF, "Couldn't find prctl_execve in $PATH"); + + sprintf(ipc_env_var, IPC_ENV_VAR "=%s", getenv(IPC_ENV_VAR)); + childpid = SAFE_FORK(); + if (childpid == 0) { + check_no_new_privs(1); + execve(path, childargv, envp); + tst_brk(TFAIL | TERRNO, + "child process failed to execute prctl_execve"); + + } else { + tst_reap_children(); + execve(path, argv, envp); + tst_brk(TFAIL | TERRNO, + "parent process failed to execute prctl_execve"); + } + cap_free(caps); + return; +} + +static void verify_prctl(void) +{ + int pid; + + pid = SAFE_FORK(); + if (pid == 0) { + do_prctl(); + exit(0); + } + tst_reap_children(); + return; +} + +static struct tst_test test = { + .test_all = verify_prctl, + .forks_child = 1, + .needs_root = 1, + .child_needs_reinit = 1, +}; diff --git a/testcases/kernel/syscalls/prctl/prctl06_execve.c b/testcases/kernel/syscalls/prctl/prctl06_execve.c new file mode 100644 index 000000000..84c28551c --- /dev/null +++ b/testcases/kernel/syscalls/prctl/prctl06_execve.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2019 FUJITSU LIMITED. All rights reserved. + * Author: Yang Xu <xuyang2018.jy@cn.fujitsu.com> + * + * dummy program which is used by prctl06 testcase + */ +#define TST_NO_DEFAULT_MAIN +#include <stdlib.h> +#include <sys/types.h> +#include <unistd.h> +#include <errno.h> +#include <pwd.h> +#include "tst_test.h" + +int main(int argc, char **argv) +{ + struct passwd *pw; + uid_t nobody_uid; + gid_t nobody_gid; + + tst_reinit(); + if (argc != 2) + tst_brk(TFAIL, "argc is %d, expected 2", argc); + + pw = SAFE_GETPWNAM("nobody"); + nobody_uid = pw->pw_uid; + nobody_gid = pw->pw_gid; + /*positive check*/ + TEST(setgid(nobody_gid)); + if (TST_RET == -1) + tst_res(TFAIL | TTERRNO, + "%s setgid(%d) isn't permmit", argv[1], nobody_gid); + else + tst_res(TPASS, "%s setgid(%d) succeed expectedly", + argv[1], nobody_gid); + /*negative check*/ + TEST(setuid(nobody_uid)); + if (TST_RET == -1) + tst_res(TPASS | TTERRNO, + "%s setuid(%d) isn't permmit", argv[1], nobody_uid); + else + tst_res(TFAIL, " %s setuid(%d) succeed unexpectedly", + argv[1], nobody_gid); + return 0; +}
Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com> --- include/lapi/prctl.h | 5 + runtest/syscalls | 1 + testcases/kernel/syscalls/prctl/.gitignore | 1 + testcases/kernel/syscalls/prctl/Makefile | 2 + testcases/kernel/syscalls/prctl/prctl06.c | 117 ++++++++++++++++++ .../kernel/syscalls/prctl/prctl06_execve.c | 46 +++++++ 6 files changed, 172 insertions(+) create mode 100644 testcases/kernel/syscalls/prctl/prctl06.c create mode 100644 testcases/kernel/syscalls/prctl/prctl06_execve.c