test_sysctl: test against int proc_dointvec() array support

Add a few initial respective tests for an array:

  o Echoing values separated by spaces works
  o Echoing only first elements will set first elements
  o Confirm PAGE_SIZE limit still applies even if an array is used

Link: http://lkml.kernel.org/r/20170630224431.17374-7-mcgrof@kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/lib/test_sysctl.c b/lib/test_sysctl.c
index 53db3513ab0829bb0f4d6a3901022bc387f5dff7..3dd801c1c85b3ce179b44968cb9fe33f5ee45c30 100644 (file)
--- a/lib/test_sysctl.c
+++ b/lib/test_sysctl.c
@@ -42,6 +42,7 @@ static int i_one_hundred = 100;
 struct test_sysctl_data {
        int int_0001;
        int int_0002;
+       int int_0003[4];
 
        unsigned int uint_0001;
 
@@ -52,6 +53,11 @@ static struct test_sysctl_data test_data = {
        .int_0001 = 60,
        .int_0002 = 1,
 
+       .int_0003[0] = 0,
+       .int_0003[1] = 1,
+       .int_0003[2] = 2,
+       .int_0003[3] = 3,
+
        .uint_0001 = 314,
 
        .string_0001 = "(none)",
@@ -75,6 +81,13 @@ static struct ctl_table test_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec,
        },
+       {
+               .procname       = "int_0003",
+               .data           = &test_data.int_0003,
+               .maxlen         = sizeof(test_data.int_0003),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec,
+       },
        {
                .procname       = "uint_0001",
                .data           = &test_data.uint_0001,

diff --git a/tools/testing/selftests/sysctl/sysctl.sh b/tools/testing/selftests/sysctl/sysctl.sh
index abeef675a8845f109fb4daec6afec966a76fa850..ec232c3cfcaac3b8f52936eabb908a0c316183f8 100644 (file)
--- a/tools/testing/selftests/sysctl/sysctl.sh
+++ b/tools/testing/selftests/sysctl/sysctl.sh
@@ -33,6 +33,7 @@ ALL_TESTS="0001:1:1"
 ALL_TESTS="$ALL_TESTS 0002:1:1"
 ALL_TESTS="$ALL_TESTS 0003:1:1"
 ALL_TESTS="$ALL_TESTS 0004:1:1"
+ALL_TESTS="$ALL_TESTS 0005:3:1"
 
 test_modprobe()
 {
@@ -108,6 +109,10 @@ test_reqs()
                echo "$0: You need getconf installed"
                exit 1
        fi
+       if ! which diff 2> /dev/null > /dev/null; then
+               echo "$0: You need diff installed"
+               exit 1
+       fi
 }
 
 function load_req_mod()
@@ -167,6 +172,12 @@ verify()
        return 0
 }
 
+verify_diff_w()
+{
+       echo "$TEST_STR" | diff -q -w -u - $1
+       return $?
+}
+
 test_rc()
 {
        if [[ $rc != 0 ]]; then
@@ -352,6 +363,74 @@ run_limit_digit_int()
        test_rc
 }
 
+# You used an int array
+run_limit_digit_int_array()
+{
+       echo -n "Testing array works as expected ... "
+       TEST_STR="4 3 2 1"
+       echo -n $TEST_STR > $TARGET
+
+       if ! verify_diff_w "${TARGET}"; then
+               echo "FAIL" >&2
+               rc=1
+       else
+               echo "ok"
+       fi
+       test_rc
+
+       echo -n "Testing skipping trailing array elements works ... "
+       # Do not reset_vals, carry on the values from the last test.
+       # If we only echo in two digits the last two are left intact
+       TEST_STR="100 101"
+       echo -n $TEST_STR > $TARGET
+       # After we echo in, to help diff we need to set on TEST_STR what
+       # we expect the result to be.
+       TEST_STR="100 101 2 1"
+
+       if ! verify_diff_w "${TARGET}"; then
+               echo "FAIL" >&2
+               rc=1
+       else
+               echo "ok"
+       fi
+       test_rc
+
+       echo -n "Testing PAGE_SIZE limit on array works ... "
+       # Do not reset_vals, carry on the values from the last test.
+       # Even if you use an int array, you are still restricted to
+       # MAX_DIGITS, this is a known limitation. Test limit works.
+       LIMIT=$((MAX_DIGITS -1))
+       TEST_STR="9"
+       (perl -e 'print " " x '$LIMIT';'; echo "${TEST_STR}") | \
+               dd of="${TARGET}" 2>/dev/null
+
+       TEST_STR="9 101 2 1"
+       if ! verify_diff_w "${TARGET}"; then
+               echo "FAIL" >&2
+               rc=1
+       else
+               echo "ok"
+       fi
+       test_rc
+
+       echo -n "Testing exceeding PAGE_SIZE limit fails as expected ... "
+       # Do not reset_vals, carry on the values from the last test.
+       # Now go over limit.
+       LIMIT=$((MAX_DIGITS))
+       TEST_STR="7"
+       (perl -e 'print " " x '$LIMIT';'; echo "${TEST_STR}") | \
+               dd of="${TARGET}" 2>/dev/null
+
+       TEST_STR="7 101 2 1"
+       if verify_diff_w "${TARGET}"; then
+               echo "FAIL" >&2
+               rc=1
+       else
+               echo "ok"
+       fi
+       test_rc
+}
+
 # You are using an unsigned int
 run_limit_digit_uint()
 {
@@ -512,6 +591,15 @@ sysctl_test_0004()
        run_limit_digit_uint
 }
 
+sysctl_test_0005()
+{
+       TARGET="${SYSCTL}/int_0003"
+       reset_vals
+       ORIG=$(cat "${TARGET}")
+
+       run_limit_digit_int_array
+}
+
 list_tests()
 {
        echo "Test ID list:"
@@ -524,6 +612,7 @@ list_tests()
        echo "0002 x $(get_test_count 0002) - tests proc_dostring()"
        echo "0003 x $(get_test_count 0003) - tests proc_dointvec()"
        echo "0004 x $(get_test_count 0004) - tests proc_douintvec()"
+       echo "0005 x $(get_test_count 0005) - tests proc_douintvec() array"
 }
 
 test_reqs