diff options
Diffstat (limited to 'src/core/execute.c')
-rw-r--r-- | src/core/execute.c | 53 |
1 files changed, 51 insertions, 2 deletions
diff --git a/src/core/execute.c b/src/core/execute.c index 5eb3f13695..2cef70e668 100644 --- a/src/core/execute.c +++ b/src/core/execute.c @@ -25,6 +25,7 @@ #include <signal.h> #include <string.h> #include <sys/capability.h> +#include <sys/mman.h> #include <sys/personality.h> #include <sys/prctl.h> #include <sys/socket.h> @@ -1190,6 +1191,45 @@ finish: return r; } +static int apply_memory_deny_write_execute(const ExecContext *c) { + scmp_filter_ctx *seccomp; + int r; + + assert(c); + + seccomp = seccomp_init(SCMP_ACT_ALLOW); + if (!seccomp) + return -ENOMEM; + + r = seccomp_rule_add( + seccomp, + SCMP_ACT_KILL, + SCMP_SYS(mmap), + 1, + SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC|PROT_WRITE, PROT_EXEC|PROT_WRITE)); + if (r < 0) + goto finish; + + r = seccomp_rule_add( + seccomp, + SCMP_ACT_KILL, + SCMP_SYS(mprotect), + 1, + SCMP_A2(SCMP_CMP_MASKED_EQ, PROT_EXEC, PROT_EXEC)); + if (r < 0) + goto finish; + + r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); + if (r < 0) + goto finish; + + r = seccomp_load(seccomp); + +finish: + seccomp_release(seccomp); + return r; +} + #endif static void do_idle_pipe_dance(int idle_pipe[4]) { @@ -1912,6 +1952,13 @@ static int exec_child( } } + if (context->memory_deny_write_execute) { + r = apply_memory_deny_write_execute(context); + if (r < 0) { + *exit_status = EXIT_SECCOMP; + return r; + } + } if (use_syscall_filter) { r = apply_seccomp(context); if (r < 0) { @@ -2371,7 +2418,8 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) { "%sPrivateDevices: %s\n" "%sProtectHome: %s\n" "%sProtectSystem: %s\n" - "%sIgnoreSIGPIPE: %s\n", + "%sIgnoreSIGPIPE: %s\n" + "%sMemoryDenyWriteExecute: %s\n", prefix, c->umask, prefix, c->working_directory ? c->working_directory : "/", prefix, c->root_directory ? c->root_directory : "/", @@ -2381,7 +2429,8 @@ void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) { prefix, yes_no(c->private_devices), prefix, protect_home_to_string(c->protect_home), prefix, protect_system_to_string(c->protect_system), - prefix, yes_no(c->ignore_sigpipe)); + prefix, yes_no(c->ignore_sigpipe), + prefix, yes_no(c->memory_deny_write_execute)); STRV_FOREACH(e, c->environment) fprintf(f, "%sEnvironment: %s\n", prefix, *e); |