diff options
author | Xin Li <delphij@google.com> | 2023-08-14 15:37:25 -0700 |
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committer | Xin Li <delphij@google.com> | 2023-08-14 15:37:25 -0700 |
commit | 94ac09491592cdd6bb278dd14387abfaa883e7da (patch) | |
tree | 8b0a33cf8947283abdba0d74b104f2400fc6ac45 | |
parent | 11c0b06b54e0492b7fec14aede564f0034b7b975 (diff) | |
parent | d1f37c215b0d3083f2467b7dd24a697789c0bcca (diff) | |
download | dtc-94ac09491592cdd6bb278dd14387abfaa883e7da.tar.gz |
Merge Android U (ab/10368041)tmp_amf_298295554
Bug: 291102124
Merged-In: I40f39f20268fa51c3f5c690e89f8853a5aff0566
Change-Id: Ic2996360fe99f05286bbe22c375053e2c249a762
-rw-r--r-- | fuzzing/Android.bp | 1 | ||||
-rw-r--r-- | fuzzing/corpus/crash-a5b94d95681291f3057eea7f0233c8f1529b2f59 | bin | 0 -> 1369 bytes | |||
-rw-r--r-- | fuzzing/corpus/hardy-octopus | bin | 0 -> 1171 bytes | |||
-rw-r--r-- | fuzzing/corpus/header-truncated | bin | 0 -> 40 bytes | |||
-rw-r--r-- | fuzzing/corpus/header-v-1 | bin | 0 -> 40 bytes | |||
-rw-r--r-- | fuzzing/corpus/header-v0 | bin | 0 -> 40 bytes | |||
-rw-r--r-- | fuzzing/corpus/meson-g12a-sei510-android.dtb | bin | 0 -> 1363 bytes | |||
-rw-r--r-- | fuzzing/corpus/oob_by_one | bin | 0 -> 256 bytes | |||
-rw-r--r-- | fuzzing/corpus/quirks.dtb | bin | 0 -> 327 bytes | |||
-rw-r--r-- | fuzzing/libfdt_fuzzer.c | 78 | ||||
-rw-r--r-- | libfdt/fdt_ro.c | 24 |
11 files changed, 101 insertions, 2 deletions
diff --git a/fuzzing/Android.bp b/fuzzing/Android.bp index 5c22cb4..857c611 100644 --- a/fuzzing/Android.bp +++ b/fuzzing/Android.bp @@ -19,3 +19,4 @@ cc_fuzz { }, host_supported: true, } + diff --git a/fuzzing/corpus/crash-a5b94d95681291f3057eea7f0233c8f1529b2f59 b/fuzzing/corpus/crash-a5b94d95681291f3057eea7f0233c8f1529b2f59 Binary files differnew file mode 100644 index 0000000..dbab42e --- /dev/null +++ b/fuzzing/corpus/crash-a5b94d95681291f3057eea7f0233c8f1529b2f59 diff --git a/fuzzing/corpus/hardy-octopus b/fuzzing/corpus/hardy-octopus Binary files differnew file mode 100644 index 0000000..81615e9 --- /dev/null +++ b/fuzzing/corpus/hardy-octopus diff --git a/fuzzing/corpus/header-truncated b/fuzzing/corpus/header-truncated Binary files differnew file mode 100644 index 0000000..1db29d8 --- /dev/null +++ b/fuzzing/corpus/header-truncated diff --git a/fuzzing/corpus/header-v-1 b/fuzzing/corpus/header-v-1 Binary files differnew file mode 100644 index 0000000..a773d07 --- /dev/null +++ b/fuzzing/corpus/header-v-1 diff --git a/fuzzing/corpus/header-v0 b/fuzzing/corpus/header-v0 Binary files differnew file mode 100644 index 0000000..f22ec6a --- /dev/null +++ b/fuzzing/corpus/header-v0 diff --git a/fuzzing/corpus/meson-g12a-sei510-android.dtb b/fuzzing/corpus/meson-g12a-sei510-android.dtb Binary files differnew file mode 100644 index 0000000..317175d --- /dev/null +++ b/fuzzing/corpus/meson-g12a-sei510-android.dtb diff --git a/fuzzing/corpus/oob_by_one b/fuzzing/corpus/oob_by_one Binary files differnew file mode 100644 index 0000000..216523c --- /dev/null +++ b/fuzzing/corpus/oob_by_one diff --git a/fuzzing/corpus/quirks.dtb b/fuzzing/corpus/quirks.dtb Binary files differnew file mode 100644 index 0000000..676024a --- /dev/null +++ b/fuzzing/corpus/quirks.dtb diff --git a/fuzzing/libfdt_fuzzer.c b/fuzzing/libfdt_fuzzer.c index 89fe3c2..b271714 100644 --- a/fuzzing/libfdt_fuzzer.c +++ b/fuzzing/libfdt_fuzzer.c @@ -59,6 +59,24 @@ static bool phandle_is_valid(uint32_t phandle) { return phandle != 0 && phandle != UINT32_MAX; } +static void walk_node_properties(const void *device_tree, int node) { + int property, len = 0; + + fdt_for_each_property_offset(property, device_tree, node) { + const struct fdt_property *prop = fdt_get_property_by_offset(device_tree, + property, &len); + if (!prop) + continue; + check_mem(prop->data, fdt32_to_cpu(prop->len)); + + const char *prop_name = fdt_string(device_tree, prop->nameoff); + if (prop_name != NULL) { + check_mem(prop_name, strlen(prop_name)); + } + } +} + + static void walk_device_tree(const void *device_tree, int parent_node) { int len = 0; const char *node_name = fdt_get_name(device_tree, parent_node, &len); @@ -72,6 +90,30 @@ static void walk_device_tree(const void *device_tree, int parent_node) { assert(node >= 0); // it should at least find parent_node } + char path_buf[64]; + if(fdt_get_path(device_tree, parent_node, path_buf, sizeof(path_buf)) == 0) { + fdt_path_offset(device_tree, path_buf); + } + + fdt_parent_offset(device_tree, parent_node); + + // Exercise sub-node search string functions + fdt_subnode_offset(device_tree, parent_node, "a"); + fdt_get_property(device_tree, parent_node, "reg", &len); + + // Check for a stringlist node called 'stringlist' (added to corpus) + const int sl_count = fdt_stringlist_count(device_tree, + parent_node, "stringlist"); + if (sl_count > 0) { + for (int i = 0; i < sl_count; i++) { + fdt_stringlist_get(device_tree, parent_node, "stringlist", i, &len); + } + + fdt_stringlist_search(device_tree, parent_node, "stringlist", "a"); + } + + walk_node_properties(device_tree, parent_node); + // recursively walk the node's children for (int node = fdt_first_subnode(device_tree, parent_node); node >= 0; node = fdt_next_subnode(device_tree, node)) { @@ -80,15 +122,49 @@ static void walk_device_tree(const void *device_tree, int parent_node) { } +static void walk_mem_rsv(const void *device_tree) { + const int n = fdt_num_mem_rsv(device_tree); + uint64_t address, size; + + for (int i = 0; i < n; i++) { + fdt_get_mem_rsv(device_tree, i, &address, &size); + } +} + + // Information on device tree is available in external/dtc/Documentation/ // folder. int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { + int rc; + // Non-zero return values are reserved for future use. if (size < FDT_V17_SIZE) return 0; - if (fdt_check_full(data, size) != 0) return 0; + // Produce coverage of checking function + rc = fdt_check_full(data, size); + fdt_strerror(rc); + // Don't continue if the library rejected the input + if (rc != 0) return 0; + + // Cover reading functions walk_device_tree(data, /* parent_node */ 0); + walk_mem_rsv(data); + + // Cover phandle functions + uint32_t phandle; + fdt_generate_phandle(data, &phandle); + + // Try and get a path by alias + fdt_path_offset(data, "a"); + + // Try to get an alias + fdt_get_alias(data, "a"); + + // Exercise common search functions + fdt_node_offset_by_compatible(data, 0, "a"); + fdt_node_offset_by_prop_value(data, 0, "x", "42", 3); return 0; } + diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c index 87d736b..a62ec78 100644 --- a/libfdt/fdt_ro.c +++ b/libfdt/fdt_ro.c @@ -10,6 +10,14 @@ #include "libfdt_internal.h" +/* Check if a buffer contains a nul-terminated string. + * Used for checking property values which should be strings. + */ +static bool is_nul_string(const char *buf, const size_t buf_len) { + return buf_len > 0 && buf[buf_len - 1] == '\0' && + strnlen(buf, buf_len) == buf_len - 1; +} + static int fdt_nodename_eq_(const void *fdt, int offset, const char *s, int len) { @@ -531,13 +539,27 @@ uint32_t fdt_get_phandle(const void *fdt, int nodeoffset) const char *fdt_get_alias_namelen(const void *fdt, const char *name, int namelen) { + const char *prop; int aliasoffset; + int prop_len; aliasoffset = fdt_path_offset(fdt, "/aliases"); if (aliasoffset < 0) return NULL; - return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL); + prop = fdt_getprop_namelen(fdt, aliasoffset, name, namelen, &prop_len); + if (prop && !can_assume(VALID_INPUT)) { + /* Validate the alias value. From the devicetree spec v0.3: + * "An alias value is a device path and is encoded as a string. + * The value representes the full path to a node, ..." + * A full path must start at the root to prevent recursion. + */ + if (prop_len == 0 || *prop != '/' || !is_nul_string(prop, prop_len)) { + prop = NULL; + } + } + + return prop; } const char *fdt_get_alias(const void *fdt, const char *name) |