diff options
Diffstat (limited to 'scripts/gcc-plugins')
| -rw-r--r-- | scripts/gcc-plugins/Kconfig | 4 | ||||
| -rw-r--r-- | scripts/gcc-plugins/arm_ssp_per_task_plugin.c | 103 | ||||
| -rw-r--r-- | scripts/gcc-plugins/stackleak_plugin.c | 8 |
3 files changed, 112 insertions, 3 deletions
diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig index 0d5c799688f0..d45f7f36b859 100644 --- a/scripts/gcc-plugins/Kconfig +++ b/scripts/gcc-plugins/Kconfig @@ -190,4 +190,8 @@ config STACKLEAK_RUNTIME_DISABLE runtime to control kernel stack erasing for kernels built with CONFIG_GCC_PLUGIN_STACKLEAK. +config GCC_PLUGIN_ARM_SSP_PER_TASK + bool + depends on GCC_PLUGINS && ARM + endif diff --git a/scripts/gcc-plugins/arm_ssp_per_task_plugin.c b/scripts/gcc-plugins/arm_ssp_per_task_plugin.c new file mode 100644 index 000000000000..de70b8470971 --- /dev/null +++ b/scripts/gcc-plugins/arm_ssp_per_task_plugin.c @@ -0,0 +1,103 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "gcc-common.h" + +__visible int plugin_is_GPL_compatible; + +static unsigned int sp_mask, canary_offset; + +static unsigned int arm_pertask_ssp_rtl_execute(void) +{ + rtx_insn *insn; + + for (insn = get_insns(); insn; insn = NEXT_INSN(insn)) { + const char *sym; + rtx body; + rtx masked_sp; + + /* + * Find a SET insn involving a SYMBOL_REF to __stack_chk_guard + */ + if (!INSN_P(insn)) + continue; + body = PATTERN(insn); + if (GET_CODE(body) != SET || + GET_CODE(SET_SRC(body)) != SYMBOL_REF) + continue; + sym = XSTR(SET_SRC(body), 0); + if (strcmp(sym, "__stack_chk_guard")) + continue; + + /* + * Replace the source of the SET insn with an expression that + * produces the address of the copy of the stack canary value + * stored in struct thread_info + */ + masked_sp = gen_reg_rtx(Pmode); + + emit_insn_before(gen_rtx_SET(masked_sp, + gen_rtx_AND(Pmode, + stack_pointer_rtx, + GEN_INT(sp_mask))), + insn); + + SET_SRC(body) = gen_rtx_PLUS(Pmode, masked_sp, + GEN_INT(canary_offset)); + } + return 0; +} + +#define PASS_NAME arm_pertask_ssp_rtl + +#define NO_GATE +#include "gcc-generate-rtl-pass.h" + +__visible int plugin_init(struct plugin_name_args *plugin_info, + struct plugin_gcc_version *version) +{ + const char * const plugin_name = plugin_info->base_name; + const int argc = plugin_info->argc; + const struct plugin_argument *argv = plugin_info->argv; + int tso = 0; + int i; + + if (!plugin_default_version_check(version, &gcc_version)) { + error(G_("incompatible gcc/plugin versions")); + return 1; + } + + for (i = 0; i < argc; ++i) { + if (!strcmp(argv[i].key, "disable")) + return 0; + + /* all remaining options require a value */ + if (!argv[i].value) { + error(G_("no value supplied for option '-fplugin-arg-%s-%s'"), + plugin_name, argv[i].key); + return 1; + } + + if (!strcmp(argv[i].key, "tso")) { + tso = atoi(argv[i].value); + continue; + } + + if (!strcmp(argv[i].key, "offset")) { + canary_offset = atoi(argv[i].value); + continue; + } + error(G_("unknown option '-fplugin-arg-%s-%s'"), + plugin_name, argv[i].key); + return 1; + } + + /* create the mask that produces the base of the stack */ + sp_mask = ~((1U << (12 + tso)) - 1); + + PASS_INFO(arm_pertask_ssp_rtl, "expand", 1, PASS_POS_INSERT_AFTER); + + register_callback(plugin_info->base_name, PLUGIN_PASS_MANAGER_SETUP, + NULL, &arm_pertask_ssp_rtl_pass_info); + + return 0; +} diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c index 2f48da98b5d4..dbd37460c573 100644 --- a/scripts/gcc-plugins/stackleak_plugin.c +++ b/scripts/gcc-plugins/stackleak_plugin.c @@ -363,10 +363,12 @@ __visible int plugin_init(struct plugin_name_args *plugin_info, PASS_POS_INSERT_BEFORE); /* - * The stackleak_cleanup pass should be executed after the - * "reload" pass, when the stack frame size is final. + * The stackleak_cleanup pass should be executed before the "*free_cfg" + * pass. It's the moment when the stack frame size is already final, + * function prologues and epilogues are generated, and the + * machine-dependent code transformations are not done. */ - PASS_INFO(stackleak_cleanup, "reload", 1, PASS_POS_INSERT_AFTER); + PASS_INFO(stackleak_cleanup, "*free_cfg", 1, PASS_POS_INSERT_BEFORE); if (!plugin_default_version_check(version, &gcc_version)) { error(G_("incompatible gcc/plugin versions")); |