Add a new test get_next_tag_invalid_prop_len, which covers fdt_next_tag(), when it is passed an corrupted blob, with invalid property len values. The test runs twice, on a blob in sw and finished state. Signed-off-by: Tadeusz Struk <tadeusz.struk@xxxxxxxxxx> --- v6: * Remove RET_FAIL and call FAIL directly. * Fix typos v5: * Add back fdt_finish_reservemap() instead of directly calling fdt_set_off_dt_strings() * Call the test twice, on the blob in sw, and finished state * Use the new fdt_get_property_by_offset_w() helper to get the pointer to the property at a given address. v4: * I didn't keep track of the changes in the test code, but this version should have all the comments addressed. --- tests/.gitignore | 1 + tests/Makefile.tests | 2 +- tests/get_next_tag_invalid_prop_len.c | 100 ++++++++++++++++++++++++++ tests/meson.build | 1 + tests/run_tests.sh | 1 + 5 files changed, 104 insertions(+), 1 deletion(-) create mode 100644 tests/get_next_tag_invalid_prop_len.c diff --git a/tests/.gitignore b/tests/.gitignore index 03bdde2..3376ed9 100644 --- a/tests/.gitignore +++ b/tests/.gitignore @@ -74,3 +74,4 @@ tmp.* /truncated_memrsv /utilfdt_test /value-labels +/get_next_tag_invalid_prop_len diff --git a/tests/Makefile.tests b/tests/Makefile.tests index 2d36c5d..2c5b4c9 100644 --- a/tests/Makefile.tests +++ b/tests/Makefile.tests @@ -4,7 +4,7 @@ LIB_TESTS_L = get_mem_rsv \ get_path supernode_atdepth_offset parent_offset \ node_offset_by_prop_value node_offset_by_phandle \ node_check_compatible node_offset_by_compatible \ - get_alias \ + get_alias get_next_tag_invalid_prop_len \ char_literal \ sized_cells \ notfound \ diff --git a/tests/get_next_tag_invalid_prop_len.c b/tests/get_next_tag_invalid_prop_len.c new file mode 100644 index 0000000..25d57c3 --- /dev/null +++ b/tests/get_next_tag_invalid_prop_len.c @@ -0,0 +1,100 @@ +// SPDX-License-Identifier: LGPL-2.1-or-later +/* + * libfdt - Flat Device Tree manipulation + * Testcase for fdt_next_tag() + */ +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <stdint.h> + +#include <libfdt.h> +#include "tests.h" +#include "testdata.h" + +#define FDT_SIZE 65536 +#define CHECK_ERR(err) \ +({ if (err) \ + FAIL("%s: %d: %s", __FILE__, __LINE__, fdt_strerror(err)); \ +}) + +static void fdt_next_tag_test(bool fdt_finished) +{ + struct fdt_property *prp; + void *fdt; + int nextoff = 0, offset, err; + uint32_t tag; + + fdt = malloc(FDT_SIZE); + if (!fdt) + FAIL("Can't allocate memory"); + err = fdt_create(fdt, FDT_SIZE); + CHECK_ERR(err); + err = fdt_finish_reservemap(fdt); + CHECK_ERR(err); + /* Create a root node and add two properties */ + err = fdt_begin_node(fdt, ""); + CHECK_ERR(err); + err = fdt_property_u32(fdt, "prop-int-32", 0x1234); + CHECK_ERR(err); + err = fdt_property_u32(fdt, "prop2-int-32", 0x4321); + CHECK_ERR(err); + err = fdt_end_node(fdt); + CHECK_ERR(err); + if (fdt_finished) { + /* Call fdt_finish to set the correct fdt state. */ + err = fdt_finish(fdt); + CHECK_ERR(err); + } + + offset = fdt_first_property_offset(fdt, 0); + if (offset <= 0) + FAIL("Invalid offset %x, expected value greater than 0, finished=%d\n", + offset, fdt_finished); + + /* Normal case */ + tag = fdt_next_tag(fdt, offset, &nextoff); + if (tag != FDT_PROP) + FAIL("Invalid tag %x, expected FDT_PROP, finished=%d\n", + tag, fdt_finished); + if (nextoff <= 0) + FAIL("Invalid nextoff %d, expected value greater than 0, finished=%d", + nextoff, fdt_finished); + + /* Get a writable ptr to the first property and corrupt the length */ + prp = fdt_get_property_by_offset_w(fdt, offset, NULL); + if (!prp) + FAIL("Bad property pointer, finished=%d", fdt_finished); + + /* int overflow case */ + prp->len = cpu_to_fdt32(0xFFFFFFFA); + tag = fdt_next_tag(fdt, offset, &nextoff); + if (tag != FDT_END) + FAIL("Invalid tag %x, expected premature FDT_END, finished=%d", + tag, fdt_finished); + if (nextoff != -FDT_ERR_BADSTRUCTURE) + FAIL("Invalid nextoff, expected error -FDT_ERR_BADSTRUCTURE, finished=%d", + fdt_finished); + + /* negative offset case */ + prp->len = cpu_to_fdt32(0x7FFFFFFA); + tag = fdt_next_tag(fdt, offset, &nextoff); + if (tag != FDT_END) + FAIL("Invalid tag %x, expected premature FDT_END, finished=%d", + tag, fdt_finished); + if (nextoff != -FDT_ERR_BADSTRUCTURE) + FAIL("Invalid nextoff, expected -FDT_ERR_BADSTRUCTURE, finished=%d", + fdt_finished); + + free(fdt); +} + +int main(int argc, char *argv[]) +{ + test_init(argc, argv); + + fdt_next_tag_test(false); + fdt_next_tag_test(true); + + PASS(); +} diff --git a/tests/meson.build b/tests/meson.build index 4ac154a..29a42dd 100644 --- a/tests/meson.build +++ b/tests/meson.build @@ -47,6 +47,7 @@ tests = [ 'get_path', 'get_phandle', 'get_prop_offset', + 'get_next_tag_invalid_prop_len', 'getprop', 'incbin', 'integer-expressions', diff --git a/tests/run_tests.sh b/tests/run_tests.sh index 244df8a..46678cb 100755 --- a/tests/run_tests.sh +++ b/tests/run_tests.sh @@ -513,6 +513,7 @@ libfdt_tests () { run_dtc_test -I fs -O dts -o fs.test_tree1.test.dts $FSBASE/test_tree1 run_dtc_test -I fs -O dtb -o fs.test_tree1.test.dtb $FSBASE/test_tree1 run_test dtbs_equal_unordered -m fs.test_tree1.test.dtb test_tree1.dtb + run_test get_next_tag_invalid_prop_len ## https://github.com/dgibson/dtc/issues/64 check_tests "$SRCDIR/phandle-args-overflow.dts" clocks_property -- 2.37.3