Merge tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull syscall entry fixes from Borislav Petkov:

 - For syscall user dispatch, separate prctl operation from syscall
   redirection range specification before the API has been made official
   in 5.11.

 - Ensure tasks using the generic syscall code do trap after returning
   from a syscall when single-stepping is requested.

* tag 'core_urgent_for_v5.11_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry: Use different define for selector variable in SUD
  entry: Ensure trap after single-step on system call return

2 files changed, 13 insertions, 9 deletions

diff --git a/tools/testing/selftests/syscall_user_dispatch/sud_benchmark.c b/tools/testing/selftests/syscall_user_dispatch/sud_benchmark.c
index 6689f1183dbf..073a03702ff5 100644
--- a/tools/testing/selftests/syscall_user_dispatch/sud_benchmark.c
+++ b/tools/testing/selftests/syscall_user_dispatch/sud_benchmark.c
@@ -22,6 +22,8 @@
 # define PR_SET_SYSCALL_USER_DISPATCH	59
 # define PR_SYS_DISPATCH_OFF	0
 # define PR_SYS_DISPATCH_ON	1
+# define SYSCALL_DISPATCH_FILTER_ALLOW	0
+# define SYSCALL_DISPATCH_FILTER_BLOCK	1
 #endif
 
 #ifdef __NR_syscalls
@@ -55,8 +57,8 @@ unsigned long trapped_call_count = 0;
 unsigned long native_call_count = 0;
 
 char selector;
-#define SYSCALL_BLOCK   (selector = PR_SYS_DISPATCH_ON)
-#define SYSCALL_UNBLOCK (selector = PR_SYS_DISPATCH_OFF)
+#define SYSCALL_BLOCK   (selector = SYSCALL_DISPATCH_FILTER_BLOCK)
+#define SYSCALL_UNBLOCK (selector = SYSCALL_DISPATCH_FILTER_ALLOW)
 
 #define CALIBRATION_STEP 100000
 #define CALIBRATE_TO_SECS 5
@@ -170,7 +172,7 @@ int main(void)
 	syscall(MAGIC_SYSCALL_1);
 
 #ifdef TEST_BLOCKED_RETURN
-	if (selector == PR_SYS_DISPATCH_OFF) {
+	if (selector == SYSCALL_DISPATCH_FILTER_ALLOW) {
 		fprintf(stderr, "Failed to return with selector blocked.\n");
 		exit(-1);
 	}
diff --git a/tools/testing/selftests/syscall_user_dispatch/sud_test.c b/tools/testing/selftests/syscall_user_dispatch/sud_test.c
index 6498b050ef89..b5d592d4099e 100644
--- a/tools/testing/selftests/syscall_user_dispatch/sud_test.c
+++ b/tools/testing/selftests/syscall_user_dispatch/sud_test.c
@@ -18,6 +18,8 @@
 # define PR_SET_SYSCALL_USER_DISPATCH	59
 # define PR_SYS_DISPATCH_OFF	0
 # define PR_SYS_DISPATCH_ON	1
+# define SYSCALL_DISPATCH_FILTER_ALLOW	0
+# define SYSCALL_DISPATCH_FILTER_BLOCK	1
 #endif
 
 #ifndef SYS_USER_DISPATCH
@@ -30,8 +32,8 @@
 # define MAGIC_SYSCALL_1 (0xff00)  /* Bad Linux syscall number */
 #endif
 
-#define SYSCALL_DISPATCH_ON(x) ((x) = 1)
-#define SYSCALL_DISPATCH_OFF(x) ((x) = 0)
+#define SYSCALL_DISPATCH_ON(x) ((x) = SYSCALL_DISPATCH_FILTER_BLOCK)
+#define SYSCALL_DISPATCH_OFF(x) ((x) = SYSCALL_DISPATCH_FILTER_ALLOW)
 
 /* Test Summary:
  *
@@ -56,7 +58,7 @@
 
 TEST_SIGNAL(dispatch_trigger_sigsys, SIGSYS)
 {
-	char sel = 0;
+	char sel = SYSCALL_DISPATCH_FILTER_ALLOW;
 	struct sysinfo info;
 	int ret;
 
@@ -79,7 +81,7 @@ TEST_SIGNAL(dispatch_trigger_sigsys, SIGSYS)
 
 TEST(bad_prctl_param)
 {
-	char sel = 0;
+	char sel = SYSCALL_DISPATCH_FILTER_ALLOW;
 	int op;
 
 	/* Invalid op */
@@ -220,7 +222,7 @@ TEST_SIGNAL(bad_selector, SIGSYS)
 	sigset_t mask;
 	struct sysinfo info;
 
-	glob_sel = 0;
+	glob_sel = SYSCALL_DISPATCH_FILTER_ALLOW;
 	nr_syscalls_emulated = 0;
 	si_code = 0;
 	si_errno = 0;
@@ -288,7 +290,7 @@ TEST(direct_dispatch_range)
 {
 	int ret = 0;
 	struct sysinfo info;
-	char sel = 0;
+	char sel = SYSCALL_DISPATCH_FILTER_ALLOW;
 
 	/*
 	 * Instead of calculating libc addresses; allow the entire