[LTP] [PATCH] Added new_behavior flag to detect kernel version Kernel >= 6.11: Tests that creat() succeeds (write to executed file allowed)

[lepillai@linux.ibm.com]

From: lekshmi-cpillai <lekshmi@ktes.isst.tadn.ibm.com>

Signed-off-by: lekshmi-cpillai <lepillai@linux.ibm.com>
---
 testcases/kernel/syscalls/creat/creat07.c | 38 ++++++++++++++++-------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/testcases/kernel/syscalls/creat/creat07.c b/testcases/kernel/syscalls/creat/creat07.c
index c7b85ee69..762022301 100644
--- a/testcases/kernel/syscalls/creat/creat07.c
+++ b/testcases/kernel/syscalls/creat/creat07.c
@@ -19,6 +19,8 @@
 
 #define TEST_APP "creat07_child"
 
+static int new_behavior;
+
 static void verify_creat(void)
 {
 	pid_t pid;
@@ -33,16 +35,26 @@ static void verify_creat(void)
 
 	TEST(creat(TEST_APP, O_WRONLY));
 
-	if (TST_RET != -1) {
-		tst_res(TFAIL, "creat() succeeded unexpectedly");
-		return;
+	if (new_behavior) {
+		/* Kernel >= 6.11: write to executed file is allowed */
+		if (TST_RET != -1) {
+			SAFE_CLOSE(TST_RET);
+			tst_res(TPASS, "creat() succeeded as expected (new behavior)");
+		} else {
+			tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
+		}
+	} else {
+		/* Kernel < 6.11: write to executed file returns ETXTBSY */
+		if (TST_RET != -1) {
+			tst_res(TFAIL, "creat() succeeded unexpectedly");
+			SAFE_CLOSE(TST_RET);
+		} else if (TST_ERR == ETXTBSY) {
+			tst_res(TPASS, "creat() received ETXTBSY");
+		} else {
+			tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
+		}
 	}
 
-	if (TST_ERR == ETXTBSY)
-		tst_res(TPASS, "creat() received EXTBSY");
-	else
-		tst_res(TFAIL | TTERRNO, "creat() failed unexpectedly");
-
 	SAFE_KILL(pid, SIGKILL);
 	SAFE_WAITPID(pid, NULL, 0);
 }
@@ -50,9 +62,13 @@ static void verify_creat(void)
 static void setup(void)
 {
 	if ((tst_kvercmp(6, 11, 0)) >= 0) {
-		tst_brk(TCONF, "Skipping test, write to executed file is "
-			"allowed since 6.11-rc1.\n"
-			"2a010c412853 (\"fs: don't block i_writecount during exec\")");
+		new_behavior = 1;
+		tst_res(TINFO, "Testing new behavior: write to executed file is "
+			"allowed since 6.11-rc1 (2a010c412853)");
+	} else {
+		new_behavior = 0;
+		tst_res(TINFO, "Testing old behavior: write to executed file "
+			"returns ETXTBSY");
 	}
 }
 
-- 
2.39.1