From eed09ad261822a7bdc441ed192c6f444375e5527 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 7 Feb 2022 20:53:34 -0800 Subject: samples/seccomp: Adjust sample to also provide kill option As a quick way to test SECCOMP_RET_KILL, have a negative errno mean to kill the process. While we're in here, also swap the arch and syscall arguments so they're ordered more like how seccomp filters order them. Signed-off-by: Kees Cook --- samples/seccomp/dropper.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'samples') diff --git a/samples/seccomp/dropper.c b/samples/seccomp/dropper.c index cc0648eb389e..4bca4b70f665 100644 --- a/samples/seccomp/dropper.c +++ b/samples/seccomp/dropper.c @@ -25,7 +25,7 @@ #include #include -static int install_filter(int nr, int arch, int error) +static int install_filter(int arch, int nr, int error) { struct sock_filter filter[] = { BPF_STMT(BPF_LD+BPF_W+BPF_ABS, @@ -42,6 +42,10 @@ static int install_filter(int nr, int arch, int error) .len = (unsigned short)(sizeof(filter)/sizeof(filter[0])), .filter = filter, }; + if (error == -1) { + struct sock_filter kill = BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL); + filter[4] = kill; + } if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) { perror("prctl(NO_NEW_PRIVS)"); return 1; @@ -57,9 +61,10 @@ int main(int argc, char **argv) { if (argc < 5) { fprintf(stderr, "Usage:\n" - "dropper []\n" + "dropper []\n" "Hint: AUDIT_ARCH_I386: 0x%X\n" " AUDIT_ARCH_X86_64: 0x%X\n" + " errno == -1 means SECCOMP_RET_KILL\n" "\n", AUDIT_ARCH_I386, AUDIT_ARCH_X86_64); return 1; } -- cgit v1.2.3-59-g8ed1b