Merge tag 'seccomp-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull seccomp updates from Kees Cook:
 "Major additions:

   - sysctl and seccomp operation to discover available actions
     (tyhicks)

   - new per-filter configurable logging infrastructure and sysctl
     (tyhicks)

   - SECCOMP_RET_LOG to log allowed syscalls (tyhicks)

   - SECCOMP_RET_KILL_PROCESS as the new strictest possible action

   - self-tests for new behaviors"

[ This is the seccomp part of the security pull request during the merge
  window that was nixed due to unrelated problems   - Linus ]

* tag 'seccomp-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  samples: Unrename SECCOMP_RET_KILL
  selftests/seccomp: Test thread vs process killing
  seccomp: Implement SECCOMP_RET_KILL_PROCESS action
  seccomp: Introduce SECCOMP_RET_KILL_PROCESS
  seccomp: Rename SECCOMP_RET_KILL to SECCOMP_RET_KILL_THREAD
  seccomp: Action to log before allowing
  seccomp: Filter flag to log all actions except SECCOMP_RET_ALLOW
  seccomp: Selftest for detection of filter flag support
  seccomp: Sysctl to configure actions that are allowed to be logged
  seccomp: Operation for checking if an action is available
  seccomp: Sysctl to display available actions
  seccomp: Provide matching filter for introspection
  selftests/seccomp: Refactor RET_ERRNO tests
  selftests/seccomp: Add simple seccomp overhead benchmark
  selftests/seccomp: Add tests for basic ptrace actions

3 files changed, 18 insertions, 14 deletions

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 74d4d4e8e3db..cb708eb8accc 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -314,11 +314,7 @@ void audit_core_dumps(long signr);
 
 static inline void audit_seccomp(unsigned long syscall, long signr, int code)
 {
-	if (!audit_enabled)
-		return;
-
-	/* Force a record to be reported if a signal was delivered. */
-	if (signr || unlikely(!audit_dummy_context()))
+	if (audit_enabled && unlikely(!audit_dummy_context()))
 		__audit_seccomp(syscall, signr, code);
 }
 
diff --git a/include/linux/seccomp.h b/include/linux/seccomp.h
index ecc296c137cd..c8bef436b61d 100644
--- a/include/linux/seccomp.h
+++ b/include/linux/seccomp.h
@@ -3,7 +3,8 @@
 
 #include <uapi/linux/seccomp.h>
 
-#define SECCOMP_FILTER_FLAG_MASK	(SECCOMP_FILTER_FLAG_TSYNC)
+#define SECCOMP_FILTER_FLAG_MASK	(SECCOMP_FILTER_FLAG_TSYNC | \
+					 SECCOMP_FILTER_FLAG_LOG)
 
 #ifdef CONFIG_SECCOMP
 
diff --git a/include/uapi/linux/seccomp.h b/include/uapi/linux/seccomp.h
index 0f238a43ff1e..f6bc1dea3247 100644
--- a/include/uapi/linux/seccomp.h
+++ b/include/uapi/linux/seccomp.h
@@ -11,27 +11,34 @@
 #define SECCOMP_MODE_FILTER	2 /* uses user-supplied filter. */
 
 /* Valid operations for seccomp syscall. */
-#define SECCOMP_SET_MODE_STRICT	0
-#define SECCOMP_SET_MODE_FILTER	1
+#define SECCOMP_SET_MODE_STRICT		0
+#define SECCOMP_SET_MODE_FILTER		1
+#define SECCOMP_GET_ACTION_AVAIL	2
 
 /* Valid flags for SECCOMP_SET_MODE_FILTER */
 #define SECCOMP_FILTER_FLAG_TSYNC	1
+#define SECCOMP_FILTER_FLAG_LOG		2
 
 /*
  * All BPF programs must return a 32-bit value.
  * The bottom 16-bits are for optional return data.
- * The upper 16-bits are ordered from least permissive values to most.
+ * The upper 16-bits are ordered from least permissive values to most,
+ * as a signed value (so 0x8000000 is negative).
  *
  * 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_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_PROCESS 0x80000000U /* kill the process */
+#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 */
+#define SECCOMP_RET_LOG		 0x7ffc0000U /* allow after logging */
+#define SECCOMP_RET_ALLOW	 0x7fff0000U /* allow */
 
 /* Masks for the return value sections. */
+#define SECCOMP_RET_ACTION_FULL	0xffff0000U
 #define SECCOMP_RET_ACTION	0x7fff0000U
 #define SECCOMP_RET_DATA	0x0000ffffU