This is in preparation for further re-factoring of the register API with the rest of the code. Theoretically the read register function could overwrite the MAX_PACKET_LENGTH buffer although currently all registers are well within the size range.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org> --- gdbstub.c | 52 +++++++++++++++++++++++++++++++--------------------- 1 file changed, 31 insertions(+), 21 deletions(-) diff --git a/gdbstub.c b/gdbstub.c index 528404c1953..4c3e211890f 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -366,6 +366,7 @@ typedef struct GDBState { char syscall_buf[256]; gdb_syscall_complete_cb current_syscall_cb; GString *str_buf; + GByteArray *mem_buf; } GDBState; /* By default use no IRQs and no timers while single stepping so as to @@ -380,6 +381,7 @@ static GDBState *gdb_allocate_state(void) g_assert(!gdbserver_state); gdbserver_state = g_new0(GDBState, 1); gdbserver_state->str_buf = g_string_new(NULL); + gdbserver_state->mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH); return gdbserver_state; } @@ -566,12 +568,13 @@ static void memtohex(GString *buf, const uint8_t *mem, int len) g_string_append_c(buf, '\0'); } -static void hextomem(uint8_t *mem, const char *buf, int len) +static void hextomem(GByteArray *mem, const char *buf, int len) { int i; for(i = 0; i < len; i++) { - mem[i] = (fromhex(buf[0]) << 4) | fromhex(buf[1]); + guint8 byte = fromhex(buf[0]) << 4 | fromhex(buf[1]); + g_byte_array_append(mem, &byte, 1); buf += 2; } } @@ -1396,7 +1399,6 @@ static int cmd_parse_params(const char *data, const char *schema, typedef struct GdbCmdContext { GdbCmdVariant *params; int num_params; - uint8_t mem_buf[MAX_PACKET_LENGTH]; } GdbCmdContext; typedef void (*GdbCmdHandler)(GdbCmdContext *gdb_ctx, void *user_ctx); @@ -1489,6 +1491,7 @@ static void run_cmd_parser(GDBState *s, const char *data, } g_string_set_size(s->str_buf, 0); + g_byte_array_set_size(s->mem_buf, 0); /* In case there was an error during the command parsing we must * send a NULL packet to indicate the command is not supported */ @@ -1710,8 +1713,8 @@ static void handle_set_reg(GdbCmdContext *gdb_ctx, void *user_ctx) } reg_size = strlen(gdb_ctx->params[1].data) / 2; - hextomem(gdb_ctx->mem_buf, gdb_ctx->params[1].data, reg_size); - gdb_write_register(s->g_cpu, gdb_ctx->mem_buf, + hextomem(s->mem_buf, gdb_ctx->params[1].data, reg_size); + gdb_write_register(s->g_cpu, s->mem_buf->data, gdb_ctx->params[0].val_ull); put_packet(s, "OK"); } @@ -1731,14 +1734,16 @@ static void handle_get_reg(GdbCmdContext *gdb_ctx, void *user_ctx) return; } - reg_size = gdb_read_register(s->g_cpu, gdb_ctx->mem_buf, + reg_size = gdb_read_register(s->g_cpu, s->mem_buf->data, gdb_ctx->params[0].val_ull); if (!reg_size) { put_packet(s, "E14"); return; + } else { + g_byte_array_set_size(s->mem_buf, reg_size); } - memtohex(s->str_buf, gdb_ctx->mem_buf, reg_size); + memtohex(s->str_buf, s->mem_buf->data, reg_size); put_packet(s, s->str_buf->str); } @@ -1757,11 +1762,11 @@ static void handle_write_mem(GdbCmdContext *gdb_ctx, void *user_ctx) return; } - hextomem(gdb_ctx->mem_buf, gdb_ctx->params[2].data, + hextomem(s->mem_buf, gdb_ctx->params[2].data, gdb_ctx->params[1].val_ull); if (target_memory_rw_debug(s->g_cpu, gdb_ctx->params[0].val_ull, - gdb_ctx->mem_buf, - gdb_ctx->params[1].val_ull, true)) { + s->mem_buf->data, + s->mem_buf->len, true)) { put_packet(s, "E14"); return; } @@ -1784,14 +1789,16 @@ static void handle_read_mem(GdbCmdContext *gdb_ctx, void *user_ctx) return; } + g_byte_array_set_size(s->mem_buf, gdb_ctx->params[1].val_ull); + if (target_memory_rw_debug(s->g_cpu, gdb_ctx->params[0].val_ull, - gdb_ctx->mem_buf, - gdb_ctx->params[1].val_ull, false)) { + s->mem_buf->data, + s->mem_buf->len, false)) { put_packet(s, "E14"); return; } - memtohex(s->str_buf, gdb_ctx->mem_buf, gdb_ctx->params[1].val_ull); + memtohex(s->str_buf, s->mem_buf->data, s->mem_buf->len); put_packet(s, s->str_buf->str); } @@ -1807,9 +1814,9 @@ static void handle_write_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx) } cpu_synchronize_state(s->g_cpu); - registers = gdb_ctx->mem_buf; len = strlen(gdb_ctx->params[0].data) / 2; - hextomem(registers, gdb_ctx->params[0].data, len); + hextomem(s->mem_buf, gdb_ctx->params[0].data, len); + registers = s->mem_buf->data; for (addr = 0; addr < s->g_cpu->gdb_num_g_regs && len > 0; addr++) { reg_size = gdb_write_register(s->g_cpu, registers, addr); @@ -1827,11 +1834,13 @@ static void handle_read_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx) cpu_synchronize_state(s->g_cpu); len = 0; for (addr = 0; addr < s->g_cpu->gdb_num_g_regs; addr++) { - len += gdb_read_register(s->g_cpu, gdb_ctx->mem_buf + len, + len += gdb_read_register(s->g_cpu, s->mem_buf->data + len, addr); } + /* FIXME: This is after the fact sizing */ + g_byte_array_set_size(s->mem_buf, len); - memtohex(s->str_buf, gdb_ctx->mem_buf, len); + memtohex(s->str_buf, s->mem_buf->data, len); put_packet(s, s->str_buf->str); } @@ -2102,6 +2111,7 @@ static void handle_query_offsets(GdbCmdContext *gdb_ctx, void *user_ctx) static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx) { GDBState *s = gdbserver_state; + const guint8 zero = 0; int len; if (!gdb_ctx->num_params) { @@ -2116,11 +2126,11 @@ static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx) } len = len / 2; - hextomem(gdb_ctx->mem_buf, gdb_ctx->params[0].data, len); - gdb_ctx->mem_buf[len++] = 0; - qemu_chr_be_write(s->mon_chr, gdb_ctx->mem_buf, len); + g_byte_array_set_size(s->mem_buf, len); + hextomem(s->mem_buf, gdb_ctx->params[0].data, len); + g_byte_array_append(s->mem_buf, &zero, 1); + qemu_chr_be_write(s->mon_chr, s->mem_buf->data, s->mem_buf->len); put_packet(s, "OK"); - } #endif -- 2.20.1