From 4a25f1b97ac1fad8dca3bee5f1d22fc8cb582b37 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Mon, 16 Mar 2020 17:21:36 +0000 Subject: [PATCH] gdbstub: move mem_buf to GDBState and use GByteArray MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Richard Henderson Reviewed-by: Damien Hedde Tested-by: Damien Hedde Message-Id: <20200316172155.971-10-alex.bennee@linaro.org> --- gdbstub.c | 56 ++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 21 deletions(-) diff --git a/gdbstub.c b/gdbstub.c index f6b4282544..db537a712c 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -367,6 +367,7 @@ 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 @@ -382,6 +383,7 @@ static void init_gdbserver_state(void) memset(&gdbserver_state, 0, sizeof(GDBState)); gdbserver_state.init = true; gdbserver_state.str_buf = g_string_new(NULL); + gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH); } #ifndef CONFIG_USER_ONLY @@ -576,12 +578,13 @@ 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; } } @@ -1412,7 +1415,6 @@ 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); @@ -1503,6 +1505,7 @@ static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd) } g_string_set_size(gdbserver_state.str_buf, 0); + g_byte_array_set_size(gdbserver_state.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 */ @@ -1715,8 +1718,8 @@ 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(gdbserver_state.g_cpu, gdb_ctx->mem_buf, + hextomem(gdbserver_state.mem_buf, gdb_ctx->params[1].data, reg_size); + gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data, gdb_ctx->params[0].val_ull); put_packet("OK"); } @@ -1735,14 +1738,17 @@ static void handle_get_reg(GdbCmdContext *gdb_ctx, void *user_ctx) return; } - reg_size = gdb_read_register(gdbserver_state.g_cpu, gdb_ctx->mem_buf, + reg_size = gdb_read_register(gdbserver_state.g_cpu, + gdbserver_state.mem_buf->data, gdb_ctx->params[0].val_ull); if (!reg_size) { put_packet("E14"); return; + } else { + g_byte_array_set_size(gdbserver_state.mem_buf, reg_size); } - memtohex(gdbserver_state.str_buf, gdb_ctx->mem_buf, reg_size); + memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, reg_size); put_strbuf(); } @@ -1759,11 +1765,11 @@ static void handle_write_mem(GdbCmdContext *gdb_ctx, void *user_ctx) return; } - hextomem(gdb_ctx->mem_buf, gdb_ctx->params[2].data, + hextomem(gdbserver_state.mem_buf, gdb_ctx->params[2].data, gdb_ctx->params[1].val_ull); if (target_memory_rw_debug(gdbserver_state.g_cpu, gdb_ctx->params[0].val_ull, - gdb_ctx->mem_buf, - gdb_ctx->params[1].val_ull, true)) { + gdbserver_state.mem_buf->data, + gdbserver_state.mem_buf->len, true)) { put_packet("E14"); return; } @@ -1784,14 +1790,17 @@ static void handle_read_mem(GdbCmdContext *gdb_ctx, void *user_ctx) return; } + g_byte_array_set_size(gdbserver_state.mem_buf, gdb_ctx->params[1].val_ull); + if (target_memory_rw_debug(gdbserver_state.g_cpu, gdb_ctx->params[0].val_ull, - gdb_ctx->mem_buf, - gdb_ctx->params[1].val_ull, false)) { + gdbserver_state.mem_buf->data, + gdbserver_state.mem_buf->len, false)) { put_packet("E14"); return; } - memtohex(gdbserver_state.str_buf, gdb_ctx->mem_buf, gdb_ctx->params[1].val_ull); + memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, + gdbserver_state.mem_buf->len); put_strbuf(); } @@ -1806,9 +1815,9 @@ static void handle_write_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx) } cpu_synchronize_state(gdbserver_state.g_cpu); - registers = gdb_ctx->mem_buf; len = strlen(gdb_ctx->params[0].data) / 2; - hextomem(registers, gdb_ctx->params[0].data, len); + hextomem(gdbserver_state.mem_buf, gdb_ctx->params[0].data, len); + registers = gdbserver_state.mem_buf->data; for (addr = 0; addr < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0; addr++) { reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, addr); @@ -1825,11 +1834,14 @@ static void handle_read_all_regs(GdbCmdContext *gdb_ctx, void *user_ctx) cpu_synchronize_state(gdbserver_state.g_cpu); len = 0; for (addr = 0; addr < gdbserver_state.g_cpu->gdb_num_g_regs; addr++) { - len += gdb_read_register(gdbserver_state.g_cpu, gdb_ctx->mem_buf + len, + len += gdb_read_register(gdbserver_state.g_cpu, + gdbserver_state.mem_buf->data + len, addr); } + /* FIXME: This is after the fact sizing */ + g_byte_array_set_size(gdbserver_state.mem_buf, len); - memtohex(gdbserver_state.str_buf, gdb_ctx->mem_buf, len); + memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len); put_strbuf(); } @@ -2078,6 +2090,7 @@ static void handle_query_offsets(GdbCmdContext *gdb_ctx, void *user_ctx) #else static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx) { + const guint8 zero = 0; int len; if (!gdb_ctx->num_params) { @@ -2091,12 +2104,13 @@ static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx) return; } + g_assert(gdbserver_state.mem_buf->len == 0); len = len / 2; - hextomem(gdb_ctx->mem_buf, gdb_ctx->params[0].data, len); - gdb_ctx->mem_buf[len++] = 0; - qemu_chr_be_write(gdbserver_state.mon_chr, gdb_ctx->mem_buf, len); + hextomem(gdbserver_state.mem_buf, gdb_ctx->params[0].data, len); + g_byte_array_append(gdbserver_state.mem_buf, &zero, 1); + qemu_chr_be_write(gdbserver_state.mon_chr, gdbserver_state.mem_buf->data, + gdbserver_state.mem_buf->len); put_packet("OK"); - } #endif