seccomp: Rename SECCOMP_RET_KILL to SECCOMP_RET_KILL_THREAD

In preparation for adding SECCOMP_RET_KILL_PROCESS, rename SECCOMP_RET_KILL
to the more accurate SECCOMP_RET_KILL_THREAD.

The existing selftest values are intentionally left as SECCOMP_RET_KILL
just to be sure we're exercising the alias.

Signed-off-by: Kees Cook <keescook@chromium.org>

7 files changed, 39 insertions, 32 deletions

diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt
index b69b205501de..73aa0f12156d 100644
--- a/Documentation/networking/filter.txt
+++ b/Documentation/networking/filter.txt
@@ -337,7 +337,7 @@ Examples for low-level BPF:
   jeq #14, good           /* __NR_rt_sigprocmask */
   jeq #13, good           /* __NR_rt_sigaction */
   jeq #35, good           /* __NR_nanosleep */
-  bad: ret #0             /* SECCOMP_RET_KILL */
+  bad: ret #0             /* SECCOMP_RET_KILL_THREAD */
   good: ret #0x7fff0000   /* SECCOMP_RET_ALLOW */
 
 The above example code can be placed into a file (here called "foo"), and
diff --git a/Documentation/userspace-api/seccomp_filter.rst b/Documentation/userspace-api/seccomp_filter.rst
index f4977357daf2..d76396f2d8ed 100644
--- a/Documentation/userspace-api/seccomp_filter.rst
+++ b/Documentation/userspace-api/seccomp_filter.rst
@@ -87,11 +87,11 @@ Return values
 A seccomp filter may return any of the following values. If multiple
 filters exist, the return value for the evaluation of a given system
 call will always use the highest precedent value. (For example,
-``SECCOMP_RET_KILL`` will always take precedence.)
+``SECCOMP_RET_KILL_THREAD`` will always take precedence.)
 
 In precedence order, they are:
 
-``SECCOMP_RET_KILL``:
+``SECCOMP_RET_KILL_THREAD``:
         Results in the task exiting immediately without executing the
         system call.  The exit status of the task (``status & 0x7f``) will
         be ``SIGSYS``, not ``SIGKILL``.
diff --git a/include/uapi/linux/seccomp.h b/include/uapi/linux/seccomp.h
index f94433263e4b..5a03f699eb17 100644
--- a/include/uapi/linux/seccomp.h
+++ b/include/uapi/linux/seccomp.h
@@ -27,7 +27,8 @@
  * The ordering ensures that a min_t() over composed return values always
  * selects the least permissive choice.
  */
-#define SECCOMP_RET_KILL        0x00000000U /* kill the task immediately */
+#define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
+#define SECCOMP_RET_KILL        SECCOMP_RET_KILL_THREAD
 #define SECCOMP_RET_TRAP        0x00030000U /* disallow and force a SIGSYS */
 #define SECCOMP_RET_ERRNO       0x00050000U /* returns an errno */
 #define SECCOMP_RET_TRACE       0x7ff00000U /* pass to a tracer or disallow */
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 59cde2ed3b92..95ac54cff00f 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -192,7 +192,7 @@ static u32 seccomp_run_filters(const struct seccomp_data *sd,
 
         /* Ensure unexpected behavior doesn't result in failing open. */
         if (unlikely(WARN_ON(f == NULL)))
-                return SECCOMP_RET_KILL;
+                return SECCOMP_RET_KILL_THREAD;
 
         if (!sd) {
                 populate_seccomp_data(&sd_local);
@@ -529,15 +529,17 @@ static void seccomp_send_sigsys(int syscall, int reason)
 #endif  /* CONFIG_SECCOMP_FILTER */
 
 /* For use with seccomp_actions_logged */
-#define SECCOMP_LOG_KILL                (1 << 0)
+#define SECCOMP_LOG_KILL_THREAD         (1 << 0)
 #define SECCOMP_LOG_TRAP                (1 << 2)
 #define SECCOMP_LOG_ERRNO               (1 << 3)
 #define SECCOMP_LOG_TRACE               (1 << 4)
 #define SECCOMP_LOG_LOG                 (1 << 5)
 #define SECCOMP_LOG_ALLOW               (1 << 6)
 
-static u32 seccomp_actions_logged = SECCOMP_LOG_KILL  | SECCOMP_LOG_TRAP  |
-                                    SECCOMP_LOG_ERRNO | SECCOMP_LOG_TRACE |
+static u32 seccomp_actions_logged = SECCOMP_LOG_KILL_THREAD |
+                                    SECCOMP_LOG_TRAP  |
+                                    SECCOMP_LOG_ERRNO |
+                                    SECCOMP_LOG_TRACE |
                                     SECCOMP_LOG_LOG;
 
 static inline void seccomp_log(unsigned long syscall, long signr, u32 action,
@@ -560,13 +562,13 @@ static inline void seccomp_log(unsigned long syscall, long signr, u32 action,
         case SECCOMP_RET_LOG:
                 log = seccomp_actions_logged & SECCOMP_LOG_LOG;
                 break;
-        case SECCOMP_RET_KILL:
+        case SECCOMP_RET_KILL_THREAD:
         default:
-                log = seccomp_actions_logged & SECCOMP_LOG_KILL;
+                log = seccomp_actions_logged & SECCOMP_LOG_KILL_THREAD;
         }
 
         /*
-         * Force an audit message to be emitted when the action is RET_KILL,
+         * Force an audit message to be emitted when the action is RET_KILL_*,
          * RET_LOG, or the FILTER_FLAG_LOG bit was set and the action is
          * allowed to be logged by the admin.
          */
@@ -605,7 +607,7 @@ static void __secure_computing_strict(int this_syscall)
 #ifdef SECCOMP_DEBUG
         dump_stack();
 #endif
-        seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL, true);
+        seccomp_log(this_syscall, SIGKILL, SECCOMP_RET_KILL_THREAD, true);
         do_exit(SIGKILL);
 }
 
@@ -716,7 +718,7 @@ static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd,
                  */
                 return 0;
 
-        case SECCOMP_RET_KILL:
+        case SECCOMP_RET_KILL_THREAD:
         default:
                 seccomp_log(this_syscall, SIGSYS, action, true);
                 /* Dump core only if this is the last remaining thread. */
@@ -878,7 +880,7 @@ static long seccomp_get_action_avail(const char __user *uaction)
                 return -EFAULT;
 
         switch (action) {
-        case SECCOMP_RET_KILL:
+        case SECCOMP_RET_KILL_THREAD:
         case SECCOMP_RET_TRAP:
         case SECCOMP_RET_ERRNO:
         case SECCOMP_RET_TRACE:
@@ -1029,19 +1031,20 @@ out:
 #ifdef CONFIG_SYSCTL
 
 /* Human readable action names for friendly sysctl interaction */
-#define SECCOMP_RET_KILL_NAME           "kill"
+#define SECCOMP_RET_KILL_THREAD_NAME    "kill_thread"
 #define SECCOMP_RET_TRAP_NAME           "trap"
 #define SECCOMP_RET_ERRNO_NAME          "errno"
 #define SECCOMP_RET_TRACE_NAME          "trace"
 #define SECCOMP_RET_LOG_NAME            "log"
 #define SECCOMP_RET_ALLOW_NAME          "allow"
 
-static const char seccomp_actions_avail[] = SECCOMP_RET_KILL_NAME       " "
-                                            SECCOMP_RET_TRAP_NAME       " "
-                                            SECCOMP_RET_ERRNO_NAME      " "
-                                            SECCOMP_RET_TRACE_NAME      " "
-                                            SECCOMP_RET_LOG_NAME        " "
-                                            SECCOMP_RET_ALLOW_NAME;
+static const char seccomp_actions_avail[] =
+                                SECCOMP_RET_KILL_THREAD_NAME    " "
+                                SECCOMP_RET_TRAP_NAME           " "
+                                SECCOMP_RET_ERRNO_NAME          " "
+                                SECCOMP_RET_TRACE_NAME          " "
+                                SECCOMP_RET_LOG_NAME            " "
+                                SECCOMP_RET_ALLOW_NAME;
 
 struct seccomp_log_name {
         u32             log;
@@ -1049,7 +1052,7 @@ struct seccomp_log_name {
 };
 
 static const struct seccomp_log_name seccomp_log_names[] = {
-        { SECCOMP_LOG_KILL, SECCOMP_RET_KILL_NAME },
+        { SECCOMP_LOG_KILL_THREAD, SECCOMP_RET_KILL_THREAD_NAME },
         { SECCOMP_LOG_TRAP, SECCOMP_RET_TRAP_NAME },
         { SECCOMP_LOG_ERRNO, SECCOMP_RET_ERRNO_NAME },
         { SECCOMP_LOG_TRACE, SECCOMP_RET_TRACE_NAME },
diff --git a/samples/seccomp/bpf-direct.c b/samples/seccomp/bpf-direct.c
index 151ec3f52189..235ce3c49ee9 100644
--- a/samples/seccomp/bpf-direct.c
+++ b/samples/seccomp/bpf-direct.c
@@ -129,7 +129,7 @@ static int install_filter(void)
                 /* Check that read is only using stdin. */
                 BPF_STMT(BPF_LD+BPF_W+BPF_ABS, syscall_arg(0)),
                 BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, STDIN_FILENO, 4, 0),
-                BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL),
+                BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL_THREAD),
 
                 /* Check that write is only using stdout */
                 BPF_STMT(BPF_LD+BPF_W+BPF_ABS, syscall_arg(0)),
@@ -139,7 +139,7 @@ static int install_filter(void)
 
                 BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
                 BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_TRAP),
-                BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL),
+                BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL_THREAD),
         };
         struct sock_fprog prog = {
                 .len = (unsigned short)(sizeof(filter)/sizeof(filter[0])),
diff --git a/samples/seccomp/bpf-helper.h b/samples/seccomp/bpf-helper.h
index 1d8de9edd858..83dbe79cbe2c 100644
--- a/samples/seccomp/bpf-helper.h
+++ b/samples/seccomp/bpf-helper.h
@@ -44,7 +44,7 @@ void seccomp_bpf_print(struct sock_filter *filter, size_t count);
 #define ALLOW \
         BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW)
 #define DENY \
-        BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL)
+        BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL_THREAD)
 #define JUMP(labels, label) \
         BPF_JUMP(BPF_JMP+BPF_JA, FIND_LABEL((labels), (label)), \
                  JUMP_JT, JUMP_JF)
diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 7372958eccb5..a3ba39a32449 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -68,15 +68,18 @@
 #define SECCOMP_MODE_FILTER 2
 #endif
 
+#ifndef SECCOMP_RET_KILL_THREAD
+#define SECCOMP_RET_KILL_THREAD  0x00000000U /* kill the thread */
+#endif
 #ifndef SECCOMP_RET_KILL
-#define SECCOMP_RET_KILL        0x00000000U /* kill the task immediately */
-#define SECCOMP_RET_TRAP        0x00030000U /* disallow and force a SIGSYS */
-#define SECCOMP_RET_ERRNO       0x00050000U /* returns an errno */
-#define SECCOMP_RET_TRACE       0x7ff00000U /* pass to a tracer or disallow */
-#define SECCOMP_RET_ALLOW       0x7fff0000U /* allow */
+#define SECCOMP_RET_KILL         SECCOMP_RET_KILL_THREAD
+#define SECCOMP_RET_TRAP         0x00030000U /* disallow and force a SIGSYS */
+#define SECCOMP_RET_ERRNO        0x00050000U /* returns an errno */
+#define SECCOMP_RET_TRACE        0x7ff00000U /* pass to a tracer or disallow */
+#define SECCOMP_RET_ALLOW        0x7fff0000U /* allow */
 #endif
 #ifndef SECCOMP_RET_LOG
-#define SECCOMP_RET_LOG       0x7ffc0000U /* allow after logging */
+#define SECCOMP_RET_LOG          0x7ffc0000U /* allow after logging */
 #endif
 
 #ifndef SECCOMP_RET_ACTION
@@ -2696,7 +2699,7 @@ TEST_SIGNAL(filter_flag_log, SIGSYS)
 
 TEST(get_action_avail)
 {
-        __u32 actions[] = { SECCOMP_RET_KILL,  SECCOMP_RET_TRAP,
+        __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
                             SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
                             SECCOMP_RET_LOG,   SECCOMP_RET_ALLOW };
         __u32 unknown_action = 0x10000000U;