commit 55b5a6d8e39c4f3474a8033c4b9af5244cd68384
Author: Kamil Rytarowski <n54@gmx.com>
Date:   Fri May 22 18:48:40 2020 +0200

    Cherry-pick:
    
    Module Name:    src
    Committed By:   kamil
    Date:           Mon May 11 20:58:48 UTC 2020
    
    Modified Files:
            src/tests/lib/libc/sys: t_ptrace_fork_wait.h
    
    Log Message:
    Fix race in fork_singalmasked
    
    ELF RTLD after rtld.c r. 1.204 introduced locking that wraps the fork
    syscall. This locking changes signal mask of the calling process during
    the forking process.
    
    Instead of comparing old and new signal mask, just after the forking
    operation, check whether the expected signal is still masked and in
    another test whether it is still ignored.
    
    To generate a diff of this commit:
    cvs rdiff -u -r1.1 -r1.2 src/tests/lib/libc/sys/t_ptrace_fork_wait.h
    
    Please note that diffs are not public domain; they are subject to the
    copyright notices on the relevant files.

diff --git a/tests/lib/libc/sys/t_ptrace_wait.c b/tests/lib/libc/sys/t_ptrace_wait.c
index 931cd96093b7..44ea33a51111 100644
--- a/tests/lib/libc/sys/t_ptrace_wait.c
+++ b/tests/lib/libc/sys/t_ptrace_wait.c
@@ -5824,11 +5824,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 
 	FORKEE_ASSERT_EQ(sysctl(name, namelen, &kp, &len, NULL, 0), 0);
 
-	if (masked)
-		kp_sigmask = kp.p_sigmask;
-
-	if (ignored)
-		kp_sigignore = kp.p_sigignore;
+	kp_sigmask = kp.p_sigmask;
+	kp_sigignore = kp.p_sigignore;
 
 	DPRINTF("Set 0%s%s%s%s in EVENT_MASK for the child %d\n",
 	    strcmp(fn, "spawn") == 0 ? "|PTRACE_POSIX_SPAWN" : "",
@@ -5874,8 +5871,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigmask.__bits[0], kp.p_sigmask.__bits[1],
 			    kp.p_sigmask.__bits[2], kp.p_sigmask.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigmask, &kp.p_sigmask,
-			    sizeof(kp_sigmask)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigmask,
+			    SIGTRAP));
 		}
 
 		if (ignored) {
@@ -5891,8 +5888,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigignore.__bits[0], kp.p_sigignore.__bits[1],
 			    kp.p_sigignore.__bits[2], kp.p_sigignore.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigignore, &kp.p_sigignore,
-			    sizeof(kp_sigignore)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigignore,
+			    SIGTRAP));
 		}
 
 		SYSCALL_REQUIRE(
@@ -5937,8 +5934,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigmask.__bits[0], kp.p_sigmask.__bits[1],
 			    kp.p_sigmask.__bits[2], kp.p_sigmask.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigmask, &kp.p_sigmask,
-			    sizeof(kp_sigmask)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigmask,
+			    SIGTRAP));
 		}
 
 		if (ignored) {
@@ -5954,8 +5951,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigignore.__bits[0], kp.p_sigignore.__bits[1],
 			    kp.p_sigignore.__bits[2], kp.p_sigignore.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigignore, &kp.p_sigignore,
-			    sizeof(kp_sigignore)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigignore,
+			    SIGTRAP));
 		}
 
 		SYSCALL_REQUIRE(
@@ -6016,8 +6013,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigmask.__bits[0], kp.p_sigmask.__bits[1],
 			    kp.p_sigmask.__bits[2], kp.p_sigmask.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigmask, &kp.p_sigmask,
-			    sizeof(kp_sigmask)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigmask,
+			    SIGTRAP));
 		}
 
 		if (ignored) {
@@ -6033,8 +6030,8 @@ fork2_body(const char *fn, bool masked, bool ignored)
 			    kp.p_sigignore.__bits[0], kp.p_sigignore.__bits[1],
 			    kp.p_sigignore.__bits[2], kp.p_sigignore.__bits[3]);
 
-			ATF_REQUIRE(!memcmp(&kp_sigignore, &kp.p_sigignore,
-			    sizeof(kp_sigignore)));
+			ATF_REQUIRE(sigismember((sigset_t *)&kp.p_sigignore,
+			    SIGTRAP));
 		}
 
 		SYSCALL_REQUIRE(