From e44465d2599d5fc4bf66a6469202898c32b75edf Mon Sep 17 00:00:00 2001 From: Wenyong Huang Date: Thu, 25 Apr 2024 20:07:57 +0800 Subject: [PATCH] Enhance wasm loader checks for opcode br_table (#3352) Fix the integer overflow issue when checking target branch depth in opcode br_table, and fix is_32bit_type not check VALUE_TYPE_ANY issue, which may cause wasm_loader_push_frame_offset push extra unneeded offset. --- core/iwasm/interpreter/wasm_loader.c | 29 +++++++++----------- core/iwasm/interpreter/wasm_mini_loader.c | 32 +++++++++++++++-------- 2 files changed, 34 insertions(+), 27 deletions(-) diff --git a/core/iwasm/interpreter/wasm_loader.c b/core/iwasm/interpreter/wasm_loader.c index 9aab9febd..1bc51d7b9 100644 --- a/core/iwasm/interpreter/wasm_loader.c +++ b/core/iwasm/interpreter/wasm_loader.c @@ -293,7 +293,10 @@ type2str(uint8 type) static bool is_32bit_type(uint8 type) { - if (type == VALUE_TYPE_I32 || type == VALUE_TYPE_F32 + if (type == VALUE_TYPE_I32 + || type == VALUE_TYPE_F32 + /* the operand stack is in polymorphic state */ + || type == VALUE_TYPE_ANY #if WASM_ENABLE_GC != 0 || (sizeof(uintptr_t) == 4 && wasm_is_type_reftype(type)) #elif WASM_ENABLE_REF_TYPES != 0 @@ -11533,16 +11536,17 @@ re_scan: #endif POP_I32(); - /* Get the default depth and check it */ + /* Get each depth and check it */ p_org = p; for (i = 0; i <= count; i++) { read_leb_uint32(p, p_end, depth); - } - if (loader_ctx->csp_num < depth + 1) { - set_error_buf(error_buf, error_buf_size, - "unknown label, " - "unexpected end of section or function"); - goto fail; + bh_assert(loader_ctx->csp_num > 0); + if (loader_ctx->csp_num - 1 < depth) { + set_error_buf(error_buf, error_buf_size, + "unknown label, " + "unexpected end of section or function"); + goto fail; + } } p = p_org; @@ -11558,12 +11562,6 @@ re_scan: for (i = 0; i <= count; i++) { p_org = p; read_leb_uint32(p, p_end, depth); - if (loader_ctx->csp_num < depth + 1) { - set_error_buf(error_buf, error_buf_size, - "unknown label, " - "unexpected end of section or function"); - goto fail; - } p = p_org; /* Get the target block's arity and check it */ @@ -11965,8 +11963,7 @@ re_scan: loader_ctx->reftype_map_num--; } #endif - if (is_32bit_type(*(loader_ctx->frame_ref - 1)) - || *(loader_ctx->frame_ref - 1) == VALUE_TYPE_ANY) { + if (is_32bit_type(*(loader_ctx->frame_ref - 1))) { loader_ctx->frame_ref--; loader_ctx->stack_cell_num--; #if WASM_ENABLE_FAST_INTERP != 0 diff --git a/core/iwasm/interpreter/wasm_mini_loader.c b/core/iwasm/interpreter/wasm_mini_loader.c index d5282c675..20084e146 100644 --- a/core/iwasm/interpreter/wasm_mini_loader.c +++ b/core/iwasm/interpreter/wasm_mini_loader.c @@ -67,7 +67,10 @@ set_error_buf(char *error_buf, uint32 error_buf_size, const char *string) static bool is_32bit_type(uint8 type) { - if (type == VALUE_TYPE_I32 || type == VALUE_TYPE_F32 + if (type == VALUE_TYPE_I32 + || type == VALUE_TYPE_F32 + /* the operand stack is in polymorphic state */ + || type == VALUE_TYPE_ANY #if WASM_ENABLE_REF_TYPES != 0 || type == VALUE_TYPE_FUNCREF || type == VALUE_TYPE_EXTERNREF #endif @@ -4237,7 +4240,7 @@ wasm_loader_pop_frame_ref(WASMLoaderContext *ctx, uint8 type, char *error_buf, ctx->frame_ref--; ctx->stack_cell_num--; - if (is_32bit_type(type) || *ctx->frame_ref == VALUE_TYPE_ANY) + if (is_32bit_type(type)) return true; ctx->frame_ref--; @@ -6351,13 +6354,11 @@ re_scan: case WASM_OP_BR_TABLE: { uint8 *ret_types = NULL; - uint32 ret_count = 0; + uint32 ret_count = 0, depth = 0; #if WASM_ENABLE_FAST_INTERP == 0 - uint8 *p_depth_begin, *p_depth; - uint32 depth, j; BrTableCache *br_table_cache = NULL; - - p_org = p - 1; + uint8 *p_depth_begin, *p_depth, *p_opcode = p - 1; + uint32 j; #endif read_leb_uint32(p, p_end, count); @@ -6366,6 +6367,16 @@ re_scan: #endif POP_I32(); + /* Get each depth and check it */ + p_org = p; + for (i = 0; i <= count; i++) { + read_leb_uint32(p, p_end, depth); + bh_assert(loader_ctx->csp_num > 0); + bh_assert(loader_ctx->csp_num - 1 >= depth); + (void)depth; + } + p = p_org; + #if WASM_ENABLE_FAST_INTERP == 0 p_depth_begin = p_depth = p; #endif @@ -6391,8 +6402,8 @@ re_scan: error_buf, error_buf_size))) { goto fail; } - *p_org = EXT_OP_BR_TABLE_CACHE; - br_table_cache->br_table_op_addr = p_org; + *p_opcode = EXT_OP_BR_TABLE_CACHE; + br_table_cache->br_table_op_addr = p_opcode; br_table_cache->br_count = count; /* Copy previous depths which are one byte */ for (j = 0; j < i; j++) { @@ -6623,8 +6634,7 @@ re_scan: && !cur_block->is_stack_polymorphic)); if (available_stack_cell > 0) { - if (is_32bit_type(*(loader_ctx->frame_ref - 1)) - || *(loader_ctx->frame_ref - 1) == VALUE_TYPE_ANY) { + if (is_32bit_type(*(loader_ctx->frame_ref - 1))) { loader_ctx->frame_ref--; loader_ctx->stack_cell_num--; #if WASM_ENABLE_FAST_INTERP != 0