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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 07:27:36 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 07:27:36 +0400 |
commit | cb60e3e65c1b96a4d6444a7a13dc7dd48bc15a2b (patch) | |
tree | 4322be35db678f6299348a76ad60a2023954af7d /samples/seccomp/dropper.c | |
parent | 99262a3dafa3290866512ddfb32609198f8973e9 (diff) | |
parent | ff2bb047c4bce9742e94911eeb44b4d6ff4734ab (diff) | |
download | linux-cb60e3e65c1b96a4d6444a7a13dc7dd48bc15a2b.tar.xz |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"New notable features:
- The seccomp work from Will Drewry
- PR_{GET,SET}_NO_NEW_PRIVS from Andy Lutomirski
- Longer security labels for Smack from Casey Schaufler
- Additional ptrace restriction modes for Yama by Kees Cook"
Fix up trivial context conflicts in arch/x86/Kconfig and include/linux/filter.h
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (65 commits)
apparmor: fix long path failure due to disconnected path
apparmor: fix profile lookup for unconfined
ima: fix filename hint to reflect script interpreter name
KEYS: Don't check for NULL key pointer in key_validate()
Smack: allow for significantly longer Smack labels v4
gfp flags for security_inode_alloc()?
Smack: recursive tramsmute
Yama: replace capable() with ns_capable()
TOMOYO: Accept manager programs which do not start with / .
KEYS: Add invalidation support
KEYS: Do LRU discard in full keyrings
KEYS: Permit in-place link replacement in keyring list
KEYS: Perform RCU synchronisation on keys prior to key destruction
KEYS: Announce key type (un)registration
KEYS: Reorganise keys Makefile
KEYS: Move the key config into security/keys/Kconfig
KEYS: Use the compat keyctl() syscall wrapper on Sparc64 for Sparc32 compat
Yama: remove an unused variable
samples/seccomp: fix dependencies on arch macros
Yama: add additional ptrace scopes
...
Diffstat (limited to 'samples/seccomp/dropper.c')
-rw-r--r-- | samples/seccomp/dropper.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/samples/seccomp/dropper.c b/samples/seccomp/dropper.c new file mode 100644 index 000000000000..c69c347c7011 --- /dev/null +++ b/samples/seccomp/dropper.c @@ -0,0 +1,68 @@ +/* + * Naive system call dropper built on seccomp_filter. + * + * Copyright (c) 2012 The Chromium OS Authors <chromium-os-dev@chromium.org> + * Author: Will Drewry <wad@chromium.org> + * + * The code may be used by anyone for any purpose, + * and can serve as a starting point for developing + * applications using prctl(PR_SET_SECCOMP, 2, ...). + * + * When run, returns the specified errno for the specified + * system call number against the given architecture. + * + * Run this one as root as PR_SET_NO_NEW_PRIVS is not called. + */ + +#include <errno.h> +#include <linux/audit.h> +#include <linux/filter.h> +#include <linux/seccomp.h> +#include <linux/unistd.h> +#include <stdio.h> +#include <stddef.h> +#include <stdlib.h> +#include <sys/prctl.h> +#include <unistd.h> + +static int install_filter(int nr, int arch, int error) +{ + struct sock_filter filter[] = { + BPF_STMT(BPF_LD+BPF_W+BPF_ABS, + (offsetof(struct seccomp_data, arch))), + BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, arch, 0, 3), + BPF_STMT(BPF_LD+BPF_W+BPF_ABS, + (offsetof(struct seccomp_data, nr))), + BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, nr, 0, 1), + BPF_STMT(BPF_RET+BPF_K, + SECCOMP_RET_ERRNO|(error & SECCOMP_RET_DATA)), + BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW), + }; + struct sock_fprog prog = { + .len = (unsigned short)(sizeof(filter)/sizeof(filter[0])), + .filter = filter, + }; + if (prctl(PR_SET_SECCOMP, 2, &prog)) { + perror("prctl"); + return 1; + } + return 0; +} + +int main(int argc, char **argv) +{ + if (argc < 5) { + fprintf(stderr, "Usage:\n" + "dropper <syscall_nr> <arch> <errno> <prog> [<args>]\n" + "Hint: AUDIT_ARCH_I386: 0x%X\n" + " AUDIT_ARCH_X86_64: 0x%X\n" + "\n", AUDIT_ARCH_I386, AUDIT_ARCH_X86_64); + return 1; + } + if (install_filter(strtol(argv[1], NULL, 0), strtol(argv[2], NULL, 0), + strtol(argv[3], NULL, 0))) + return 1; + execv(argv[4], &argv[4]); + printf("Failed to execv\n"); + return 255; +} |