| Message ID | 20190306214226.14598-8-tobin@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | lib/string: Add strscpy_pad() function | expand |
On Wed, Mar 6, 2019 at 1:43 PM Tobin C. Harding <tobin@kernel.org> wrote: > > Add a test module for the new strscpy_pad() function. Tie it into the > kselftest infrastructure for lib/ tests. > > Signed-off-by: Tobin C. Harding <tobin@kernel.org> Yay! :) Acked-by: Kees Cook <keescook@chromium.org> -Kees > --- > lib/Kconfig.debug | 3 + > lib/Makefile | 1 + > lib/test_strscpy.c | 150 +++++++++++++++++++++++++ > tools/testing/selftests/lib/Makefile | 2 +- > tools/testing/selftests/lib/config | 1 + > tools/testing/selftests/lib/strscpy.sh | 17 +++ > 6 files changed, 173 insertions(+), 1 deletion(-) > create mode 100644 lib/test_strscpy.c > create mode 100755 tools/testing/selftests/lib/strscpy.sh > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index d4df5b24d75e..441c1571495c 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1805,6 +1805,9 @@ config TEST_HEXDUMP > config TEST_STRING_HELPERS > tristate "Test functions located in the string_helpers module at runtime" > > +config TEST_STRSCPY > + tristate "Test strscpy*() family of functions at runtime" > + > config TEST_KSTRTOX > tristate "Test kstrto*() family of functions at runtime" > > diff --git a/lib/Makefile b/lib/Makefile > index e1b59da71418..82e027f73a3e 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -68,6 +68,7 @@ obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o > obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o > obj-$(CONFIG_TEST_PRINTF) += test_printf.o > obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o > +obj-$(CONFIG_TEST_STRSCPY) += test_strscpy.o > obj-$(CONFIG_TEST_BITFIELD) += test_bitfield.o > obj-$(CONFIG_TEST_UUID) += test_uuid.o > obj-$(CONFIG_TEST_XARRAY) += test_xarray.o > diff --git a/lib/test_strscpy.c b/lib/test_strscpy.c > new file mode 100644 > index 000000000000..95665e8a0f97 > --- /dev/null > +++ b/lib/test_strscpy.c > @@ -0,0 +1,150 @@ > +// SPDX-License-Identifier: GPL-2.0+ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > +#include <linux/string.h> > + > +#include "../tools/testing/selftests/kselftest_module.h" > + > +/* > + * Kernel module for testing 'strscpy' family of functions. > + */ > + > +KSTM_MODULE_GLOBALS(); > + > +/* > + * tc() - Run a specific test case. > + * @src: Source string, argument to strscpy_pad() > + * @count: Size of destination buffer, argument to strscpy_pad() > + * @expected: Expected return value from call to strscpy_pad() > + * @terminator: 1 if there should be a terminating null byte 0 otherwise. > + * @chars: Number of characters from the src string expected to be > + * written to the dst buffer. > + * @pad: Number of pad characters expected (in the tail of dst buffer). > + * (@pad does not include the null terminator byte.) > + * > + * Calls strscpy_pad() and verifies the return value and state of the > + * destination buffer after the call returns. > + */ > +static int __init tc(char *src, int count, int expected, > + int chars, int terminator, int pad) > +{ > + int nr_bytes_poison; > + int max_expected; > + int max_count; > + int written; > + char buf[6]; > + int index, i; > + const char POISON = 'z'; > + > + total_tests++; > + > + if (!src) { > + pr_err("null source string not supported\n"); > + return -1; > + } > + > + memset(buf, POISON, sizeof(buf)); > + /* Future proofing test suite, validate args */ > + max_count = sizeof(buf) - 2; /* Space for null and to verify overflow */ > + max_expected = count - 1; /* Space for the null */ > + if (count > max_count) { > + pr_err("count (%d) is too big (%d) ... aborting", count, max_count); > + return -1; > + } > + if (expected > max_expected) { > + pr_warn("expected (%d) is bigger than can possibly be returned (%d)", > + expected, max_expected); > + } > + > + written = strscpy_pad(buf, src, count); > + if ((written) != (expected)) { > + pr_err("%d != %d (written, expected)\n", written, expected); > + goto fail; > + } > + > + if (count && written == -E2BIG) { > + if (strncmp(buf, src, count - 1) != 0) { > + pr_err("buffer state invalid for -E2BIG\n"); > + goto fail; > + } > + if (buf[count - 1] != '\0') { > + pr_err("too big string is not null terminated correctly\n"); > + goto fail; > + } > + } > + > + for (i = 0; i < chars; i++) { > + if (buf[i] != src[i]) { > + pr_err("buf[i]==%c != src[i]==%c\n", buf[i], src[i]); > + goto fail; > + } > + } > + > + if (terminator) { > + if (buf[count - 1] != '\0') { > + pr_err("string is not null terminated correctly\n"); > + goto fail; > + } > + } > + > + for (i = 0; i < pad; i++) { > + index = chars + terminator + i; > + if (buf[index] != '\0') { > + pr_err("padding missing at index: %d\n", i); > + goto fail; > + } > + } > + > + nr_bytes_poison = sizeof(buf) - chars - terminator - pad; > + for (i = 0; i < nr_bytes_poison; i++) { > + index = sizeof(buf) - 1 - i; /* Check from the end back */ > + if (buf[index] != POISON) { > + pr_err("poison value missing at index: %d\n", i); > + goto fail; > + } > + } > + > + return 0; > +fail: > + failed_tests++; > + return -1; > +} > + > +static void __init selftest(void) > +{ > + /* > + * tc() uses a destination buffer of size 6 and needs at > + * least 2 characters spare (one for null and one to check for > + * overflow). This means we should only call tc() with > + * strings up to a maximum of 4 characters long and 'count' > + * should not exceed 4. To test with longer strings increase > + * the buffer size in tc(). > + */ > + > + /* tc(src, count, expected, chars, terminator, pad) */ > + KSTM_CHECK_ZERO(tc("a", 0, -E2BIG, 0, 0, 0)); > + KSTM_CHECK_ZERO(tc("", 0, -E2BIG, 0, 0, 0)); > + > + KSTM_CHECK_ZERO(tc("a", 1, -E2BIG, 0, 1, 0)); > + KSTM_CHECK_ZERO(tc("", 1, 0, 0, 1, 0)); > + > + KSTM_CHECK_ZERO(tc("ab", 2, -E2BIG, 1, 1, 0)); > + KSTM_CHECK_ZERO(tc("a", 2, 1, 1, 1, 0)); > + KSTM_CHECK_ZERO(tc("", 2, 0, 0, 1, 1)); > + > + KSTM_CHECK_ZERO(tc("abc", 3, -E2BIG, 2, 1, 0)); > + KSTM_CHECK_ZERO(tc("ab", 3, 2, 2, 1, 0)); > + KSTM_CHECK_ZERO(tc("a", 3, 1, 1, 1, 1)); > + KSTM_CHECK_ZERO(tc("", 3, 0, 0, 1, 2)); > + > + KSTM_CHECK_ZERO(tc("abcd", 4, -E2BIG, 3, 1, 0)); > + KSTM_CHECK_ZERO(tc("abc", 4, 3, 3, 1, 0)); > + KSTM_CHECK_ZERO(tc("ab", 4, 2, 2, 1, 1)); > + KSTM_CHECK_ZERO(tc("a", 4, 1, 1, 1, 2)); > + KSTM_CHECK_ZERO(tc("", 4, 0, 0, 1, 3)); > +} > + > +KSTM_MODULE_LOADERS(test_strscpy); > +MODULE_AUTHOR("Tobin C. Harding <tobin@kernel.org>"); > +MODULE_LICENSE("GPL"); > diff --git a/tools/testing/selftests/lib/Makefile b/tools/testing/selftests/lib/Makefile > index 70d5711e3ac8..9f26635f3e57 100644 > --- a/tools/testing/selftests/lib/Makefile > +++ b/tools/testing/selftests/lib/Makefile > @@ -3,6 +3,6 @@ > # No binaries, but make sure arg-less "make" doesn't trigger "run_tests" > all: > > -TEST_PROGS := printf.sh bitmap.sh prime_numbers.sh > +TEST_PROGS := printf.sh bitmap.sh prime_numbers.sh strscpy.sh > > include ../lib.mk > diff --git a/tools/testing/selftests/lib/config b/tools/testing/selftests/lib/config > index 126933bcc950..14a77ea4a8da 100644 > --- a/tools/testing/selftests/lib/config > +++ b/tools/testing/selftests/lib/config > @@ -1,3 +1,4 @@ > CONFIG_TEST_PRINTF=m > CONFIG_TEST_BITMAP=m > CONFIG_PRIME_NUMBERS=m > +CONFIG_TEST_STRSCPY=m > diff --git a/tools/testing/selftests/lib/strscpy.sh b/tools/testing/selftests/lib/strscpy.sh > new file mode 100755 > index 000000000000..f3ba4b90e602 > --- /dev/null > +++ b/tools/testing/selftests/lib/strscpy.sh > @@ -0,0 +1,17 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0+ > + > +module=test_strscpy > +description="strscpy" > + > +# > +# Shouldn't need to edit anything below here. > +# > + > +file="kselftest_module.sh" > +path="../$file" > +if [[ ! $KBUILD_SRC == "" ]]; then > + path="${KBUILD_SRC}/tools/testing/selftests/$file" > +fi > + > +$path $module $description > -- > 2.20.1 >
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index d4df5b24d75e..441c1571495c 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1805,6 +1805,9 @@ config TEST_HEXDUMP config TEST_STRING_HELPERS tristate "Test functions located in the string_helpers module at runtime" +config TEST_STRSCPY + tristate "Test strscpy*() family of functions at runtime" + config TEST_KSTRTOX tristate "Test kstrto*() family of functions at runtime" diff --git a/lib/Makefile b/lib/Makefile index e1b59da71418..82e027f73a3e 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -68,6 +68,7 @@ obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o obj-$(CONFIG_TEST_PRINTF) += test_printf.o obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o +obj-$(CONFIG_TEST_STRSCPY) += test_strscpy.o obj-$(CONFIG_TEST_BITFIELD) += test_bitfield.o obj-$(CONFIG_TEST_UUID) += test_uuid.o obj-$(CONFIG_TEST_XARRAY) += test_xarray.o diff --git a/lib/test_strscpy.c b/lib/test_strscpy.c new file mode 100644 index 000000000000..95665e8a0f97 --- /dev/null +++ b/lib/test_strscpy.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0+ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/string.h> + +#include "../tools/testing/selftests/kselftest_module.h" + +/* + * Kernel module for testing 'strscpy' family of functions. + */ + +KSTM_MODULE_GLOBALS(); + +/* + * tc() - Run a specific test case. + * @src: Source string, argument to strscpy_pad() + * @count: Size of destination buffer, argument to strscpy_pad() + * @expected: Expected return value from call to strscpy_pad() + * @terminator: 1 if there should be a terminating null byte 0 otherwise. + * @chars: Number of characters from the src string expected to be + * written to the dst buffer. + * @pad: Number of pad characters expected (in the tail of dst buffer). + * (@pad does not include the null terminator byte.) + * + * Calls strscpy_pad() and verifies the return value and state of the + * destination buffer after the call returns. + */ +static int __init tc(char *src, int count, int expected, + int chars, int terminator, int pad) +{ + int nr_bytes_poison; + int max_expected; + int max_count; + int written; + char buf[6]; + int index, i; + const char POISON = 'z'; + + total_tests++; + + if (!src) { + pr_err("null source string not supported\n"); + return -1; + } + + memset(buf, POISON, sizeof(buf)); + /* Future proofing test suite, validate args */ + max_count = sizeof(buf) - 2; /* Space for null and to verify overflow */ + max_expected = count - 1; /* Space for the null */ + if (count > max_count) { + pr_err("count (%d) is too big (%d) ... aborting", count, max_count); + return -1; + } + if (expected > max_expected) { + pr_warn("expected (%d) is bigger than can possibly be returned (%d)", + expected, max_expected); + } + + written = strscpy_pad(buf, src, count); + if ((written) != (expected)) { + pr_err("%d != %d (written, expected)\n", written, expected); + goto fail; + } + + if (count && written == -E2BIG) { + if (strncmp(buf, src, count - 1) != 0) { + pr_err("buffer state invalid for -E2BIG\n"); + goto fail; + } + if (buf[count - 1] != '\0') { + pr_err("too big string is not null terminated correctly\n"); + goto fail; + } + } + + for (i = 0; i < chars; i++) { + if (buf[i] != src[i]) { + pr_err("buf[i]==%c != src[i]==%c\n", buf[i], src[i]); + goto fail; + } + } + + if (terminator) { + if (buf[count - 1] != '\0') { + pr_err("string is not null terminated correctly\n"); + goto fail; + } + } + + for (i = 0; i < pad; i++) { + index = chars + terminator + i; + if (buf[index] != '\0') { + pr_err("padding missing at index: %d\n", i); + goto fail; + } + } + + nr_bytes_poison = sizeof(buf) - chars - terminator - pad; + for (i = 0; i < nr_bytes_poison; i++) { + index = sizeof(buf) - 1 - i; /* Check from the end back */ + if (buf[index] != POISON) { + pr_err("poison value missing at index: %d\n", i); + goto fail; + } + } + + return 0; +fail: + failed_tests++; + return -1; +} + +static void __init selftest(void) +{ + /* + * tc() uses a destination buffer of size 6 and needs at + * least 2 characters spare (one for null and one to check for + * overflow). This means we should only call tc() with + * strings up to a maximum of 4 characters long and 'count' + * should not exceed 4. To test with longer strings increase + * the buffer size in tc(). + */ + + /* tc(src, count, expected, chars, terminator, pad) */ + KSTM_CHECK_ZERO(tc("a", 0, -E2BIG, 0, 0, 0)); + KSTM_CHECK_ZERO(tc("", 0, -E2BIG, 0, 0, 0)); + + KSTM_CHECK_ZERO(tc("a", 1, -E2BIG, 0, 1, 0)); + KSTM_CHECK_ZERO(tc("", 1, 0, 0, 1, 0)); + + KSTM_CHECK_ZERO(tc("ab", 2, -E2BIG, 1, 1, 0)); + KSTM_CHECK_ZERO(tc("a", 2, 1, 1, 1, 0)); + KSTM_CHECK_ZERO(tc("", 2, 0, 0, 1, 1)); + + KSTM_CHECK_ZERO(tc("abc", 3, -E2BIG, 2, 1, 0)); + KSTM_CHECK_ZERO(tc("ab", 3, 2, 2, 1, 0)); + KSTM_CHECK_ZERO(tc("a", 3, 1, 1, 1, 1)); + KSTM_CHECK_ZERO(tc("", 3, 0, 0, 1, 2)); + + KSTM_CHECK_ZERO(tc("abcd", 4, -E2BIG, 3, 1, 0)); + KSTM_CHECK_ZERO(tc("abc", 4, 3, 3, 1, 0)); + KSTM_CHECK_ZERO(tc("ab", 4, 2, 2, 1, 1)); + KSTM_CHECK_ZERO(tc("a", 4, 1, 1, 1, 2)); + KSTM_CHECK_ZERO(tc("", 4, 0, 0, 1, 3)); +} + +KSTM_MODULE_LOADERS(test_strscpy); +MODULE_AUTHOR("Tobin C. Harding <tobin@kernel.org>"); +MODULE_LICENSE("GPL"); diff --git a/tools/testing/selftests/lib/Makefile b/tools/testing/selftests/lib/Makefile index 70d5711e3ac8..9f26635f3e57 100644 --- a/tools/testing/selftests/lib/Makefile +++ b/tools/testing/selftests/lib/Makefile @@ -3,6 +3,6 @@ # No binaries, but make sure arg-less "make" doesn't trigger "run_tests" all: -TEST_PROGS := printf.sh bitmap.sh prime_numbers.sh +TEST_PROGS := printf.sh bitmap.sh prime_numbers.sh strscpy.sh include ../lib.mk diff --git a/tools/testing/selftests/lib/config b/tools/testing/selftests/lib/config index 126933bcc950..14a77ea4a8da 100644 --- a/tools/testing/selftests/lib/config +++ b/tools/testing/selftests/lib/config @@ -1,3 +1,4 @@ CONFIG_TEST_PRINTF=m CONFIG_TEST_BITMAP=m CONFIG_PRIME_NUMBERS=m +CONFIG_TEST_STRSCPY=m diff --git a/tools/testing/selftests/lib/strscpy.sh b/tools/testing/selftests/lib/strscpy.sh new file mode 100755 index 000000000000..f3ba4b90e602 --- /dev/null +++ b/tools/testing/selftests/lib/strscpy.sh @@ -0,0 +1,17 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0+ + +module=test_strscpy +description="strscpy" + +# +# Shouldn't need to edit anything below here. +# + +file="kselftest_module.sh" +path="../$file" +if [[ ! $KBUILD_SRC == "" ]]; then + path="${KBUILD_SRC}/tools/testing/selftests/$file" +fi + +$path $module $description
Add a test module for the new strscpy_pad() function. Tie it into the kselftest infrastructure for lib/ tests. Signed-off-by: Tobin C. Harding <tobin@kernel.org> --- lib/Kconfig.debug | 3 + lib/Makefile | 1 + lib/test_strscpy.c | 150 +++++++++++++++++++++++++ tools/testing/selftests/lib/Makefile | 2 +- tools/testing/selftests/lib/config | 1 + tools/testing/selftests/lib/strscpy.sh | 17 +++ 6 files changed, 173 insertions(+), 1 deletion(-) create mode 100644 lib/test_strscpy.c create mode 100755 tools/testing/selftests/lib/strscpy.sh