[LTP] [PATCH v2 2/3] shmctl03: Fix shmmax clamped to INT_MAX in 32bit compat mode

[Petr Vorel]

From: Andrea Cervesato <andrea.cervesato@suse.com>

Kernel clamped /proc/sys/kernel/shmmax in 32bit compat mode
to INT_MAX due change in kernel v2.6.22 in commit
af7c693f14606 ("Cap shmmax at INT_MAX in compat shminfo").
Reflect that.

Reported-by: Wei Gao <wegao@suse.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Andrea Cervesato <andrea.cervesato@suse.com>
[ pvorel: check PATH_KERN_SHMMAX >= INT_MAX, separate into its own
commit, write the commit message ]
Co-developed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
 testcases/kernel/syscalls/shmctl/shmctl03.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/testcases/kernel/syscalls/shmctl/shmctl03.c b/testcases/kernel/syscalls/shmctl/shmctl03.c
index 9e1c2f0990..0a4e27ce98 100644
--- a/testcases/kernel/syscalls/shmctl/shmctl03.c
+++ b/testcases/kernel/syscalls/shmctl/shmctl03.c
@@ -30,7 +30,14 @@ static void verify_ipcinfo(void)
 	else
 		tst_res(TPASS, "shmmin = 1");
 
-	TST_ASSERT_ULONG(PATH_KERN_SHMMAX, info.shmmax);
+	if (tst_is_compat_mode() && info.shmmax == INT_MAX) {
+		unsigned long long shmmax;
+		SAFE_FILE_SCANF(PATH_KERN_SHMMAX, "%llu", &shmmax);
+		TST_EXP_LE_LU(INT_MAX, shmmax);
+	} else {
+		TST_ASSERT_ULONG(PATH_KERN_SHMMAX, info.shmmax);
+	}
+
 	TST_ASSERT_ULONG(PATH_KERN_SHMMNI, info.shmmni);
 	TST_ASSERT_ULONG(PATH_KERN_SHMALL, info.shmall);
 }
-- 
2.55.0