[LTP] [PATCH v2] hugetlb: add new testcase hugeshmat05.c
Li Wang
liwang@redhat.com
Wed Dec 16 03:59:46 CET 2015
shmget()/shmat() fails to allocate huge pages shared memory segment
with EINVAL if its size is not in the range [ N*HUGE_PAGE_SIZE - 4095,
N*HUGE_PAGE_SIZE ]. This is a problem in the memory segment size round
up algorithm. The requested size is rounded up to PAGE_SIZE (4096), but
if this roundup does not match HUGE_PAGE_SIZE (2Mb) boundary - the
allocation fails.
This bug is present in all RHEL6 versions, but not in RHEL7. It looks
like this was fixed in mainstream kernel > v3.3 by the following patches:
091d0d5 shm: fix null pointer deref when userspace specifies invalid hugepage size
af73e4d hugetlbfs: fix mmap failure in unaligned size request
42d7395 mm: support more pagesizes for MAP_HUGETLB/SHM_HUGETLB
40716e2 hugetlbfs: fix alignment of huge page requests
Signed-off-by: Li Wang <liwang@redhat.com>
---
Notes:
v1 --> v2
a.remove the key value from shmget()
b.improve the brk messages
c.just use one loop in the main function
runtest/hugetlb | 1 +
testcases/kernel/mem/.gitignore | 1 +
.../kernel/mem/hugetlb/hugeshmat/hugeshmat05.c | 136 +++++++++++++++++++++
3 files changed, 138 insertions(+)
create mode 100644 testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
diff --git a/runtest/hugetlb b/runtest/hugetlb
index 2e9f215..75e6426 100644
--- a/runtest/hugetlb
+++ b/runtest/hugetlb
@@ -10,6 +10,7 @@ hugeshmat01 hugeshmat01 -i 5
hugeshmat02 hugeshmat02 -i 5
hugeshmat03 hugeshmat03 -i 5
hugeshmat04 hugeshmat04 -i 5
+hugeshmat05 hugeshmat05 -i 5
hugeshmctl01 hugeshmctl01 -i 5
hugeshmctl02 hugeshmctl02 -i 5
diff --git a/testcases/kernel/mem/.gitignore b/testcases/kernel/mem/.gitignore
index 4702377..46c2432 100644
--- a/testcases/kernel/mem/.gitignore
+++ b/testcases/kernel/mem/.gitignore
@@ -7,6 +7,7 @@
/hugetlb/hugeshmat/hugeshmat02
/hugetlb/hugeshmat/hugeshmat03
/hugetlb/hugeshmat/hugeshmat04
+/hugetlb/hugeshmat/hugeshmat05
/hugetlb/hugeshmctl/hugeshmctl01
/hugetlb/hugeshmctl/hugeshmctl02
/hugetlb/hugeshmctl/hugeshmctl03
diff --git a/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c b/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
new file mode 100644
index 0000000..10cadea
--- /dev/null
+++ b/testcases/kernel/mem/hugetlb/hugeshmat/hugeshmat05.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2015 Red Hat, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * DESCRIPTION
+ * shmget()/shmat() fails to allocate huge pages shared memory segment
+ * with EINVAL if its size is not in the range [ N*HUGE_PAGE_SIZE - 4095,
+ * N*HUGE_PAGE_SIZE ]. This is a problem in the memory segment size round
+ * up algorithm. The requested size is rounded up to PAGE_SIZE (4096), but
+ * if this roundup does not match HUGE_PAGE_SIZE (2Mb) boundary - the
+ * allocation fails.
+ *
+ * This bug is present in all RHEL6 versions, but not in RHEL7. It looks
+ * like this was fixed in mainstream kernel > v3.3 by the following patches:
+ *
+ * 091d0d5 (shm: fix null pointer deref when userspace specifies invalid hugepage size)
+ * af73e4d (hugetlbfs: fix mmap failure in unaligned size request)
+ * 42d7395 (mm: support more pagesizes for MAP_HUGETLB/SHM_HUGETLB)
+ * 40716e2 (hugetlbfs: fix alignment of huge page requests)
+ *
+ * AUTHORS
+ * Vladislav Dronov <vdronov@redhat.com>
+ * Li Wang <liwang@redhat.com>
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+#include "test.h"
+#include "mem.h"
+#include "hugetlb.h"
+
+char *TCID = "hugeshmat05";
+int TST_TOTAL = 1;
+
+static long page_size;
+static long hpage_size;
+static long hugepages;
+
+#define N 4
+
+void setup(void)
+{
+ tst_require_root();
+ check_hugepage();
+
+ orig_hugepages = get_sys_tune("nr_hugepages");
+ page_size = getpagesize();
+ hpage_size = read_meminfo("Hugepagesize:") * 1024;
+
+ hugepages = N + 1;
+ set_sys_tune("nr_hugepages", hugepages, 1);
+
+ TEST_PAUSE;
+}
+
+void cleanup(void)
+{
+ set_sys_tune("nr_hugepages", orig_hugepages, 0);
+}
+
+void shm_test(int size)
+{
+ int shmid;
+ char *shmaddr;
+
+ shmid = shmget(IPC_PRIVATE, size, 0600 | IPC_CREAT | SHM_HUGETLB);
+ if (shmid < 0)
+ tst_brkm(TBROK | TERRNO, cleanup, "shmget failed");
+
+ shmaddr = shmat(shmid, 0, 0);
+ if (shmaddr == (char *)-1) {
+ shmctl(shmid, IPC_RMID, NULL);
+ tst_brkm(TFAIL | TERRNO, cleanup, "Bug: shared memory attach failure.");
+ }
+
+ shmaddr[0] = 1;
+ tst_resm(TINFO, "allocated %d huge bytes", size);
+
+ if (shmdt((const void *)shmaddr) != 0) {
+ shmctl(shmid, IPC_RMID, NULL);
+ tst_brkm(TFAIL | TERRNO, cleanup, "Detach failure.");
+ }
+
+ shmctl(shmid, IPC_RMID, NULL);
+}
+
+int main(int ac, char **av)
+{
+ int lc;
+
+ tst_parse_opts(ac, av, NULL, NULL);
+
+ setup();
+
+ for (lc = 0; TEST_LOOPING(lc); lc++) {
+ tst_count = 0;
+
+ /* N*hpage_size - page_size FAIL */
+ shm_test(N * hpage_size - page_size);
+
+ /* N*hpage_size - page_size - 1 SUCCESS*/
+ shm_test(N * hpage_size - page_size - 1);
+
+ /* N*hpage_size SUCCESS */
+ shm_test(N * hpage_size);
+
+ /* N*hpage_size + 1 FAIL */
+ shm_test(N * hpage_size + 1);
+
+ tst_resm(TPASS, "No regression found.");
+ }
+
+ cleanup();
+ tst_exit();
+}
--
1.8.3.1
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