[igt-dev] [PATCH igt 2/2] msm: Add test for kernel buffer permissions
Rob Clark
robdclark at gmail.com
Tue Nov 30 00:43:24 UTC 2021
From: Rob Clark <robdclark at chromium.org>
Tests that reads and/or writes to kernel managed buffers which should be
inaccessible to userspace controlled cmdstream, are indeed inaccessible.
Signed-off-by: Rob Clark <robdclark at chromium.org>
---
lib/igt_msm.h | 1 +
tests/meson.build | 1 +
tests/msm_mapping.c | 257 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 259 insertions(+)
create mode 100644 tests/msm_mapping.c
diff --git a/lib/igt_msm.h b/lib/igt_msm.h
index 421d23ed..6008020b 100644
--- a/lib/igt_msm.h
+++ b/lib/igt_msm.h
@@ -100,6 +100,7 @@ enum adreno_pm4_type3_packets {
CP_WAIT_MEM_GTE = 20,
CP_WAIT_REG_MEM = 60,
CP_MEM_WRITE = 61,
+ CP_MEM_TO_MEM = 115,
};
static inline unsigned
diff --git a/tests/meson.build b/tests/meson.build
index 7b7d6bf8..c14acf99 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -60,6 +60,7 @@ test_progs = [
'kms_vrr',
'kms_writeback',
'meta_test',
+ 'msm_mapping',
'msm_recovery',
'msm_submit',
'panfrost_get_param',
diff --git a/tests/msm_mapping.c b/tests/msm_mapping.c
new file mode 100644
index 00000000..e1474f9f
--- /dev/null
+++ b/tests/msm_mapping.c
@@ -0,0 +1,257 @@
+/*
+ * Copyright © 2021 Google, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <glob.h>
+#include <string.h>
+#include <sys/poll.h>
+#include <sys/stat.h>
+
+#include "igt.h"
+#include "igt_msm.h"
+#include "igt_io.h"
+
+/*
+ * Tests to ensure various kernel controlled buffers are mapped with the
+ * appropriate permissions (either read-only or not-accessible to userspace
+ * controlled cmdstream)
+ */
+
+/*
+ * Helper to get and clear devcore dumps
+ */
+
+static char *
+get_and_clear_devcore(void)
+{
+ glob_t glob_buf = {0};
+ char *buf = NULL;
+ int ret, fd;
+
+ ret = glob("/sys/class/devcoredump/devcd*/data", GLOB_NOSORT, NULL, &glob_buf);
+ if ((ret == GLOB_NOMATCH) || !glob_buf.gl_pathc)
+ return NULL;
+
+ fd = open(glob_buf.gl_pathv[0], O_RDWR);
+
+ if (fd >= 0) {
+ /* We don't need to read the entire devcore, the first bit is
+ * sufficient for our purposes:
+ */
+ buf = calloc(1, 0x1000);
+ igt_readn(fd, buf, 0x1000);
+
+ /* Clear the devcore: */
+ igt_writen(fd, "1", 1);
+ }
+
+ globfree(&glob_buf);
+
+ return buf;
+}
+
+/*
+ * Helper to find named buffer address
+ */
+
+static const char *
+get_line(char **buf)
+{
+ char *ret, *eol;
+
+ ret = *buf;
+ eol = strstr(*buf, "\n");
+
+ if (!eol) {
+ /* could be last line in file: */
+ *buf = NULL;
+ return ret;
+ }
+
+ *eol = '\0';
+ *buf += 1 + strlen(ret);
+
+ return ret;
+}
+
+static bool
+endswith(const char *str, const char *end)
+{
+ char *p = strstr(str, end);
+
+ /* Trim trailing whitespace: */
+ if (p) {
+ char *c = p;
+ while (c) {
+ if (isspace(*c)) {
+ *c = '\0';
+ break;
+ }
+ c++;
+ }
+ }
+
+ return p && (strlen(p) == strlen(end));
+}
+
+static uint64_t
+get_bo_addr(int drm_fd, const char *name)
+{
+ char buf[0x4000];
+ char *p = buf;
+
+ igt_debugfs_read(drm_fd, "gem", buf);
+
+ /* NOTE: the contents of the debugfs file look like:
+ *
+ * flags id ref offset kaddr size madv name
+ * 00040000: I 0 ( 1) 00000000 ffffffc0104b9000 00004096 memptrs
+ * vmas: [gpu: aspace=ffffff808bf03e00, 1000000000000,mapped,inuse=1]
+ * 00020002: I 0 ( 1) 00000000 ffffffc012001000 00032768 ring0
+ * vmas: [gpu: aspace=ffffff808bf03e00, 1000000001000,mapped,inuse=1]
+ *
+ * There can be potentially multiple vma's per bo, listed on the lines
+ * following the line for the buffer (which ends in the buffer name),
+ * but this should not be the case for any kernel controlled buffers.
+ */
+
+ while (*p) {
+ const char *line = get_line(&p);
+
+ if (endswith(line, name)) {
+ uint64_t addr, dummy;
+ int ret;
+
+ line = get_line(&p);
+
+ igt_fail_on(!line);
+
+ ret = sscanf(line, " vmas: [gpu: aspace=%"PRIx64", %"PRIx64",mapped,inuse=1]",
+ &dummy, &addr);
+ igt_fail_on(ret != 2);
+
+ return addr;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Helper for testing access to the named buffer
+ */
+static void
+do_mapping_test(struct msm_pipe *pipe, const char *buffername, bool write)
+{
+ struct msm_bo *scratch_bo = NULL;
+ struct msm_cmd *cmd;
+ char *devcore, *s;
+ uint64_t addr, fault_addr;
+ int fence_fd, ret;
+
+ /* Clear any existing devcore's: */
+ while ((devcore = get_and_clear_devcore())) {
+ free(devcore);
+ }
+
+ addr = get_bo_addr(pipe->dev->fd, buffername);
+ igt_skip_on(addr == 0);
+
+ cmd = igt_msm_cmd_new(pipe, 0x1000);
+
+ if (write) {
+ msm_cmd_pkt7(cmd, CP_MEM_WRITE, 3);
+ msm_cmd_emit(cmd, lower_32_bits(addr)); /* ADDR_LO */
+ msm_cmd_emit(cmd, upper_32_bits(addr)); /* ADDR_HI */
+ msm_cmd_emit(cmd, 0x123); /* VAL */
+ } else {
+ scratch_bo = igt_msm_bo_new(pipe->dev, 0x1000, MSM_BO_WC);
+ msm_cmd_pkt7(cmd, CP_MEM_TO_MEM, 5);
+ msm_cmd_emit(cmd, 0);
+ msm_cmd_bo (cmd, scratch_bo, 0); /* DEST_ADDR_LO/HI */
+ msm_cmd_emit(cmd, lower_32_bits(addr)); /* SRC_A_ADDR_LO */
+ msm_cmd_emit(cmd, upper_32_bits(addr)); /* SRC_A_ADDR_HI */
+ }
+
+ fence_fd = igt_msm_cmd_submit(cmd);
+
+ /* Wait for submit to complete: */
+ poll(&(struct pollfd){fence_fd, POLLIN}, 1, -1);
+ close(fence_fd);
+
+ igt_msm_bo_free(scratch_bo);
+
+ /* And now we should have gotten a devcore from the iova fault
+ * triggered by the read or write:
+ */
+ devcore = get_and_clear_devcore();
+ igt_fail_on(!devcore);
+
+ /* Make sure the devcore is from iova fault: */
+ igt_fail_on(!strstr(devcore, "fault-info"));
+
+ s = strstr(devcore, " - far: ");
+ igt_fail_on(!s);
+
+ ret = sscanf(s, " - far: %"PRIx64, &fault_addr);
+ igt_fail_on(ret != 1);
+ igt_fail_on(addr != fault_addr);
+}
+
+/*
+ * Tests for drm/msm hangcheck, recovery, and fault handling
+ */
+
+igt_main
+{
+ struct msm_device *dev = NULL;
+ struct msm_pipe *pipe = NULL;
+
+ igt_fixture {
+ dev = igt_msm_dev_open();
+ pipe = igt_msm_pipe_open(dev, 0);
+ }
+
+ igt_describe("Test ringbuffer mapping, should be read-only");
+ igt_subtest("ring") {
+ do_mapping_test(pipe, "ring0", true);
+ }
+
+ igt_describe("Test sqefw mapping, should be read-only");
+ igt_subtest("sqefw") {
+ igt_require(dev->gen >= 6);
+ do_mapping_test(pipe, "sqefw", true);
+ }
+
+ igt_describe("Test shadow mapping, should be inaccessible");
+ igt_subtest("shadow") {
+ do_mapping_test(pipe, "shadow", true);
+ do_mapping_test(pipe, "shadow", false);
+ }
+
+ igt_fixture {
+ igt_msm_pipe_close(pipe);
+ igt_msm_dev_close(dev);
+ }
+}
--
2.33.1
More information about the igt-dev
mailing list