From feee1b8c490821f29aae416a5422795f5a29263d Mon Sep 17 00:00:00 2001 From: Alexander Popov Date: Wed, 24 Jun 2020 15:33:29 +0300 Subject: gcc-plugins/stackleak: Use asm instrumentation to avoid useless register saving The kernel code instrumentation in stackleak gcc plugin works in two stages. At first, stack tracking is added to GIMPLE representation of every function (except some special cases). And later, when stack frame size info is available, stack tracking is removed from the RTL representation of the functions with small stack frame. There is an unwanted side-effect for these functions: some of them do useless work with caller-saved registers. As an example of such case, proc_sys_write without() instrumentation: 55 push %rbp 41 b8 01 00 00 00 mov $0x1,%r8d 48 89 e5 mov %rsp,%rbp e8 11 ff ff ff callq ffffffff81284610 5d pop %rbp c3 retq 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 00 00 00 proc_sys_write() with instrumentation: 55 push %rbp 48 89 e5 mov %rsp,%rbp 41 56 push %r14 41 55 push %r13 41 54 push %r12 53 push %rbx 49 89 f4 mov %rsi,%r12 48 89 fb mov %rdi,%rbx 49 89 d5 mov %rdx,%r13 49 89 ce mov %rcx,%r14 4c 89 f1 mov %r14,%rcx 4c 89 ea mov %r13,%rdx 4c 89 e6 mov %r12,%rsi 48 89 df mov %rbx,%rdi 41 b8 01 00 00 00 mov $0x1,%r8d e8 f2 fe ff ff callq ffffffff81298e80 5b pop %rbx 41 5c pop %r12 41 5d pop %r13 41 5e pop %r14 5d pop %rbp c3 retq 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1) 00 00 Let's improve the instrumentation to avoid this: 1. Make stackleak_track_stack() save all register that it works with. Use no_caller_saved_registers attribute for that function. This attribute is available for x86_64 and i386 starting from gcc-7. 2. Insert calling stackleak_track_stack() in asm: asm volatile("call stackleak_track_stack" :: "r" (current_stack_pointer)) Here we use ASM_CALL_CONSTRAINT trick from arch/x86/include/asm/asm.h. The input constraint is taken into account during gcc shrink-wrapping optimization. It is needed to be sure that stackleak_track_stack() call is inserted after the prologue of the containing function, when the stack frame is prepared. This work is a deep reengineering of the idea described on grsecurity blog https://grsecurity.net/resolving_an_unfortunate_stackleak_interaction Signed-off-by: Alexander Popov Acked-by: Miguel Ojeda Link: https://lore.kernel.org/r/20200624123330.83226-5-alex.popov@linux.com Signed-off-by: Kees Cook --- scripts/gcc-plugins/stackleak_plugin.c | 205 ++++++++++++++++++++++++++++----- 1 file changed, 177 insertions(+), 28 deletions(-) (limited to 'scripts/gcc-plugins') diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c index cc75eeba0be1..a18b0d4af456 100644 --- a/scripts/gcc-plugins/stackleak_plugin.c +++ b/scripts/gcc-plugins/stackleak_plugin.c @@ -20,7 +20,7 @@ * * Debugging: * - use fprintf() to stderr, debug_generic_expr(), debug_gimple_stmt(), - * print_rtl() and print_simple_rtl(); + * print_rtl_single() and debug_rtx(); * - add "-fdump-tree-all -fdump-rtl-all" to the plugin CFLAGS in * Makefile.gcc-plugins to see the verbose dumps of the gcc passes; * - use gcc -E to understand the preprocessing shenanigans; @@ -32,6 +32,7 @@ __visible int plugin_is_GPL_compatible; static int track_frame_size = -1; +static bool build_for_x86 = false; static const char track_function[] = "stackleak_track_stack"; /* @@ -43,32 +44,31 @@ static GTY(()) tree track_function_decl; static struct plugin_info stackleak_plugin_info = { .version = "201707101337", .help = "track-min-size=nn\ttrack stack for functions with a stack frame size >= nn bytes\n" + "arch=target_arch\tspecify target build arch\n" "disable\t\tdo not activate the plugin\n" }; -static void stackleak_add_track_stack(gimple_stmt_iterator *gsi, bool after) +static void add_stack_tracking_gcall(gimple_stmt_iterator *gsi, bool after) { gimple stmt; - gcall *stackleak_track_stack; + gcall *gimple_call; cgraph_node_ptr node; basic_block bb; - /* Insert call to void stackleak_track_stack(void) */ + /* Insert calling stackleak_track_stack() */ stmt = gimple_build_call(track_function_decl, 0); - stackleak_track_stack = as_a_gcall(stmt); - if (after) { - gsi_insert_after(gsi, stackleak_track_stack, - GSI_CONTINUE_LINKING); - } else { - gsi_insert_before(gsi, stackleak_track_stack, GSI_SAME_STMT); - } + gimple_call = as_a_gcall(stmt); + if (after) + gsi_insert_after(gsi, gimple_call, GSI_CONTINUE_LINKING); + else + gsi_insert_before(gsi, gimple_call, GSI_SAME_STMT); /* Update the cgraph */ - bb = gimple_bb(stackleak_track_stack); + bb = gimple_bb(gimple_call); node = cgraph_get_create_node(track_function_decl); gcc_assert(node); cgraph_create_edge(cgraph_get_node(current_function_decl), node, - stackleak_track_stack, bb->count, + gimple_call, bb->count, compute_call_stmt_bb_frequency(current_function_decl, bb)); } @@ -85,6 +85,79 @@ static bool is_alloca(gimple stmt) return false; } +static tree get_current_stack_pointer_decl(void) +{ + varpool_node_ptr node; + + FOR_EACH_VARIABLE(node) { + tree var = NODE_DECL(node); + tree name = DECL_NAME(var); + + if (DECL_NAME_LENGTH(var) != sizeof("current_stack_pointer") - 1) + continue; + + if (strcmp(IDENTIFIER_POINTER(name), "current_stack_pointer")) + continue; + + return var; + } + + return NULL_TREE; +} + +static void add_stack_tracking_gasm(gimple_stmt_iterator *gsi, bool after) +{ + gasm *asm_call = NULL; + tree sp_decl, input; + vec *inputs = NULL; + + /* 'no_caller_saved_registers' is currently supported only for x86 */ + gcc_assert(build_for_x86); + + /* + * Insert calling stackleak_track_stack() in asm: + * asm volatile("call stackleak_track_stack" + * :: "r" (current_stack_pointer)) + * Use ASM_CALL_CONSTRAINT trick from arch/x86/include/asm/asm.h. + * This constraint is taken into account during gcc shrink-wrapping + * optimization. It is needed to be sure that stackleak_track_stack() + * call is inserted after the prologue of the containing function, + * when the stack frame is prepared. + */ + sp_decl = get_current_stack_pointer_decl(); + if (sp_decl == NULL_TREE) { + add_stack_tracking_gcall(gsi, after); + return; + } + input = build_tree_list(NULL_TREE, build_const_char_string(2, "r")); + input = chainon(NULL_TREE, build_tree_list(input, sp_decl)); + vec_safe_push(inputs, input); + asm_call = gimple_build_asm_vec("call stackleak_track_stack", + inputs, NULL, NULL, NULL); + gimple_asm_set_volatile(asm_call, true); + if (after) + gsi_insert_after(gsi, asm_call, GSI_CONTINUE_LINKING); + else + gsi_insert_before(gsi, asm_call, GSI_SAME_STMT); + update_stmt(asm_call); +} + +static void add_stack_tracking(gimple_stmt_iterator *gsi, bool after) +{ + /* + * The 'no_caller_saved_registers' attribute is used for + * stackleak_track_stack(). If the compiler supports this attribute for + * the target arch, we can add calling stackleak_track_stack() in asm. + * That improves performance: we avoid useless operations with the + * caller-saved registers in the functions from which we will remove + * stackleak_track_stack() call during the stackleak_cleanup pass. + */ + if (lookup_attribute_spec(get_identifier("no_caller_saved_registers"))) + add_stack_tracking_gasm(gsi, after); + else + add_stack_tracking_gcall(gsi, after); +} + /* * Work with the GIMPLE representation of the code. Insert the * stackleak_track_stack() call after alloca() and into the beginning @@ -94,7 +167,7 @@ static unsigned int stackleak_instrument_execute(void) { basic_block bb, entry_bb; bool prologue_instrumented = false, is_leaf = true; - gimple_stmt_iterator gsi; + gimple_stmt_iterator gsi = { 0 }; /* * ENTRY_BLOCK_PTR is a basic block which represents possible entry @@ -123,7 +196,7 @@ static unsigned int stackleak_instrument_execute(void) continue; /* Insert stackleak_track_stack() call after alloca() */ - stackleak_add_track_stack(&gsi, true); + add_stack_tracking(&gsi, true); if (bb == entry_bb) prologue_instrumented = true; } @@ -168,7 +241,7 @@ static unsigned int stackleak_instrument_execute(void) bb = single_succ(ENTRY_BLOCK_PTR_FOR_FN(cfun)); } gsi = gsi_after_labels(bb); - stackleak_add_track_stack(&gsi, false); + add_stack_tracking(&gsi, false); return 0; } @@ -182,21 +255,10 @@ static bool large_stack_frame(void) #endif } -/* - * Work with the RTL representation of the code. - * Remove the unneeded stackleak_track_stack() calls from the functions - * which don't call alloca() and don't have a large enough stack frame size. - */ -static unsigned int stackleak_cleanup_execute(void) +static void remove_stack_tracking_gcall(void) { rtx_insn *insn, *next; - if (cfun->calls_alloca) - return 0; - - if (large_stack_frame()) - return 0; - /* * Find stackleak_track_stack() calls. Loop through the chain of insns, * which is an RTL representation of the code for a function. @@ -257,6 +319,84 @@ static unsigned int stackleak_cleanup_execute(void) } #endif } +} + +static bool remove_stack_tracking_gasm(void) +{ + bool removed = false; + rtx_insn *insn, *next; + + /* 'no_caller_saved_registers' is currently supported only for x86 */ + gcc_assert(build_for_x86); + + /* + * Find stackleak_track_stack() asm calls. Loop through the chain of + * insns, which is an RTL representation of the code for a function. + * + * The example of a matching insn: + * (insn 11 5 12 2 (parallel [ (asm_operands/v + * ("call stackleak_track_stack") ("") 0 + * [ (reg/v:DI 7 sp [ current_stack_pointer ]) ] + * [ (asm_input:DI ("r")) ] []) + * (clobber (reg:CC 17 flags)) ]) -1 (nil)) + */ + for (insn = get_insns(); insn; insn = next) { + rtx body; + + next = NEXT_INSN(insn); + + /* Check the expression code of the insn */ + if (!NONJUMP_INSN_P(insn)) + continue; + + /* + * Check the expression code of the insn body, which is an RTL + * Expression (RTX) describing the side effect performed by + * that insn. + */ + body = PATTERN(insn); + + if (GET_CODE(body) != PARALLEL) + continue; + + body = XVECEXP(body, 0, 0); + + if (GET_CODE(body) != ASM_OPERANDS) + continue; + + if (strcmp(ASM_OPERANDS_TEMPLATE(body), + "call stackleak_track_stack")) { + continue; + } + + delete_insn_and_edges(insn); + gcc_assert(!removed); + removed = true; + } + + return removed; +} + +/* + * Work with the RTL representation of the code. + * Remove the unneeded stackleak_track_stack() calls from the functions + * which don't call alloca() and don't have a large enough stack frame size. + */ +static unsigned int stackleak_cleanup_execute(void) +{ + bool removed = false; + + if (cfun->calls_alloca) + return 0; + + if (large_stack_frame()) + return 0; + + if (lookup_attribute_spec(get_identifier("no_caller_saved_registers"))) + removed = remove_stack_tracking_gasm(); + + if (!removed) + remove_stack_tracking_gcall(); return 0; } @@ -392,6 +532,15 @@ __visible int plugin_init(struct plugin_name_args *plugin_info, plugin_name, argv[i].key, argv[i].value); return 1; } + } else if (!strcmp(argv[i].key, "arch")) { + 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].value, "x86")) + build_for_x86 = true; } else { error(G_("unknown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key); -- cgit v1.2.3-70-g09d2 From 8dd70543f795d1836003754f3c60226f21433c99 Mon Sep 17 00:00:00 2001 From: Alexander Popov Date: Wed, 24 Jun 2020 15:33:30 +0300 Subject: gcc-plugins/stackleak: Add 'verbose' plugin parameter Add 'verbose' plugin parameter for stackleak gcc plugin. It can be used for printing additional info about the kernel code instrumentation. For using it add the following to scripts/Makefile.gcc-plugins: gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STACKLEAK) \ += -fplugin-arg-stackleak_plugin-verbose Signed-off-by: Alexander Popov Link: https://lore.kernel.org/r/20200624123330.83226-6-alex.popov@linux.com Signed-off-by: Kees Cook --- scripts/gcc-plugins/stackleak_plugin.c | 47 ++++++++++++++++++++++++++++++---- 1 file changed, 42 insertions(+), 5 deletions(-) (limited to 'scripts/gcc-plugins') diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c index a18b0d4af456..48e141e07956 100644 --- a/scripts/gcc-plugins/stackleak_plugin.c +++ b/scripts/gcc-plugins/stackleak_plugin.c @@ -34,6 +34,8 @@ __visible int plugin_is_GPL_compatible; static int track_frame_size = -1; static bool build_for_x86 = false; static const char track_function[] = "stackleak_track_stack"; +static bool disable = false; +static bool verbose = false; /* * Mark these global variables (roots) for gcc garbage collector since @@ -46,6 +48,7 @@ static struct plugin_info stackleak_plugin_info = { .help = "track-min-size=nn\ttrack stack for functions with a stack frame size >= nn bytes\n" "arch=target_arch\tspecify target build arch\n" "disable\t\tdo not activate the plugin\n" + "verbose\t\tprint info about the instrumentation\n" }; static void add_stack_tracking_gcall(gimple_stmt_iterator *gsi, bool after) @@ -102,6 +105,10 @@ static tree get_current_stack_pointer_decl(void) return var; } + if (verbose) { + fprintf(stderr, "stackleak: missing current_stack_pointer in %s()\n", + DECL_NAME_POINTER(current_function_decl)); + } return NULL_TREE; } @@ -195,6 +202,11 @@ static unsigned int stackleak_instrument_execute(void) if (!is_alloca(stmt)) continue; + if (verbose) { + fprintf(stderr, "stackleak: be careful, alloca() in %s()\n", + DECL_NAME_POINTER(current_function_decl)); + } + /* Insert stackleak_track_stack() call after alloca() */ add_stack_tracking(&gsi, true); if (bb == entry_bb) @@ -384,13 +396,31 @@ static bool remove_stack_tracking_gasm(void) */ static unsigned int stackleak_cleanup_execute(void) { + const char *fn = DECL_NAME_POINTER(current_function_decl); bool removed = false; - if (cfun->calls_alloca) + /* + * Leave stack tracking in functions that call alloca(). + * Additional case: + * gcc before version 7 called allocate_dynamic_stack_space() from + * expand_stack_vars() for runtime alignment of constant-sized stack + * variables. That caused cfun->calls_alloca to be set for functions + * that in fact don't use alloca(). + * For more info see gcc commit 7072df0aae0c59ae437e. + * Let's leave such functions instrumented as well. + */ + if (cfun->calls_alloca) { + if (verbose) + fprintf(stderr, "stackleak: instrument %s(): calls_alloca\n", fn); return 0; + } - if (large_stack_frame()) + /* Leave stack tracking in functions with large stack frame */ + if (large_stack_frame()) { + if (verbose) + fprintf(stderr, "stackleak: instrument %s()\n", fn); return 0; + } if (lookup_attribute_spec(get_identifier("no_caller_saved_registers"))) removed = remove_stack_tracking_gasm(); @@ -516,9 +546,6 @@ __visible int plugin_init(struct plugin_name_args *plugin_info, /* Parse the plugin arguments */ for (i = 0; i < argc; i++) { - if (!strcmp(argv[i].key, "disable")) - return 0; - if (!strcmp(argv[i].key, "track-min-size")) { if (!argv[i].value) { error(G_("no value supplied for option '-fplugin-arg-%s-%s'"), @@ -541,6 +568,10 @@ __visible int plugin_init(struct plugin_name_args *plugin_info, if (!strcmp(argv[i].value, "x86")) build_for_x86 = true; + } else if (!strcmp(argv[i].key, "disable")) { + disable = true; + } else if (!strcmp(argv[i].key, "verbose")) { + verbose = true; } else { error(G_("unknown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key); @@ -548,6 +579,12 @@ __visible int plugin_init(struct plugin_name_args *plugin_info, } } + if (disable) { + if (verbose) + fprintf(stderr, "stackleak: disabled for this translation unit\n"); + return 0; + } + /* Give the information about the plugin */ register_callback(plugin_name, PLUGIN_INFO, NULL, &stackleak_plugin_info); -- cgit v1.2.3-70-g09d2 From 6975031a31f0c72a20e464c1df4c607d6bb44fb8 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 13 Feb 2020 21:24:10 +0900 Subject: gcc-plugins: fix gcc-plugins directory path in documentation Fix typos "plgins" -> "plugins". Signed-off-by: Masahiro Yamada Acked-by: Kees Cook --- Documentation/kbuild/reproducible-builds.rst | 2 +- scripts/gcc-plugins/Kconfig | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/gcc-plugins') diff --git a/Documentation/kbuild/reproducible-builds.rst b/Documentation/kbuild/reproducible-builds.rst index 503393854e2e..3b25655e441b 100644 --- a/Documentation/kbuild/reproducible-builds.rst +++ b/Documentation/kbuild/reproducible-builds.rst @@ -101,7 +101,7 @@ Structure randomisation If you enable ``CONFIG_GCC_PLUGIN_RANDSTRUCT``, you will need to pre-generate the random seed in -``scripts/gcc-plgins/randomize_layout_seed.h`` so the same value +``scripts/gcc-plugins/randomize_layout_seed.h`` so the same value is used in rebuilds. Debug info conflicts diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig index ce0b99fb5847..ae19fb0243b9 100644 --- a/scripts/gcc-plugins/Kconfig +++ b/scripts/gcc-plugins/Kconfig @@ -78,7 +78,7 @@ config GCC_PLUGIN_RANDSTRUCT source tree isn't cleaned after kernel installation). The seed used for compilation is located at - scripts/gcc-plgins/randomize_layout_seed.h. It remains after + scripts/gcc-plugins/randomize_layout_seed.h. It remains after a make clean to allow for external modules to be compiled with the existing seed and will be removed by a make mrproper or make distclean. -- cgit v1.2.3-70-g09d2 From 496b24ec6d47f2d304a0c5836ba4b1bb5d30bab8 Mon Sep 17 00:00:00 2001 From: "Alexander A. Klimov" Date: Mon, 13 Jul 2020 15:50:18 +0200 Subject: gcc-plugins: Replace HTTP links with HTTPS ones Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov Link: https://lore.kernel.org/r/20200713135018.34708-1-grandmaster@al2klimov.de Signed-off-by: Kees Cook --- scripts/gcc-plugins/cyc_complexity_plugin.c | 2 +- scripts/gcc-plugins/sancov_plugin.c | 2 +- scripts/gcc-plugins/structleak_plugin.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts/gcc-plugins') diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c index 1909ec617431..73124c2b3edd 100644 --- a/scripts/gcc-plugins/cyc_complexity_plugin.c +++ b/scripts/gcc-plugins/cyc_complexity_plugin.c @@ -5,7 +5,7 @@ * Homepage: * https://github.com/ephox-gcc-plugins/cyclomatic_complexity * - * http://en.wikipedia.org/wiki/Cyclomatic_complexity + * https://en.wikipedia.org/wiki/Cyclomatic_complexity * The complexity M is then defined as: * M = E - N + 2P * where diff --git a/scripts/gcc-plugins/sancov_plugin.c b/scripts/gcc-plugins/sancov_plugin.c index 0f98634c20a0..caff4a6c7e9a 100644 --- a/scripts/gcc-plugins/sancov_plugin.c +++ b/scripts/gcc-plugins/sancov_plugin.c @@ -11,7 +11,7 @@ * * You can read about it more here: * https://gcc.gnu.org/viewcvs/gcc?limit_changes=0&view=revision&revision=231296 - * http://lwn.net/Articles/674854/ + * https://lwn.net/Articles/674854/ * https://github.com/google/syzkaller * https://lwn.net/Articles/677764/ * diff --git a/scripts/gcc-plugins/structleak_plugin.c b/scripts/gcc-plugins/structleak_plugin.c index e89be8f5c859..b9ef2e162107 100644 --- a/scripts/gcc-plugins/structleak_plugin.c +++ b/scripts/gcc-plugins/structleak_plugin.c @@ -11,7 +11,7 @@ * otherwise leak kernel stack to userland if they aren't properly initialized * by later code * - * Homepage: http://pax.grsecurity.net/ + * Homepage: https://pax.grsecurity.net/ * * Options: * -fplugin-arg-structleak_plugin-disable -- cgit v1.2.3-70-g09d2 From 42640b134bf44e3bac34808e8c39660c7ae42855 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 29 Jul 2020 12:15:36 +0900 Subject: kbuild: move host .so build rules to scripts/gcc-plugins/Makefile The host shared library rules are currently implemented in scripts/Makefile.host, but actually GCC-plugin is the only user of them. (The VDSO .so files are built for the target by different build rules) Hence, they do not need to be treewide available. Move all the relevant build rules to scripts/gcc-plugins/Makefile. I also optimized the build steps so *.so is directly built from .c because every upstream plugin is compiled from a single source file. I am still keeping the multi-file plugin support, which Kees Cook mentioned might be needed by out-of-tree plugins. (https://lkml.org/lkml/2019/1/11/1107) If the plugin, foo.so, is compiled from two files foo.c and foo2.c, then you can do like follows: foo-objs := foo.o foo2.o Single-file plugins do not need the *-objs notation. Signed-off-by: Masahiro Yamada Acked-by: Kees Cook --- scripts/Makefile.build | 4 +-- scripts/Makefile.clean | 3 +-- scripts/Makefile.host | 30 ++-------------------- scripts/gcc-plugins/Makefile | 61 ++++++++++++++++++++++++++++++++++++-------- 4 files changed, 55 insertions(+), 43 deletions(-) (limited to 'scripts/gcc-plugins') diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 246426fa1282..d54adf0dcf39 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -45,8 +45,8 @@ include $(kbuild-file) include scripts/Makefile.lib -# Do not include host rules unless needed -ifneq ($(hostprogs)$(hostcxxlibs-y)$(hostcxxlibs-m),) +# Do not include hostprogs rules unless needed +ifneq ($(hostprogs),) include scripts/Makefile.host endif diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean index e2c76122319d..3cdf31218198 100644 --- a/scripts/Makefile.clean +++ b/scripts/Makefile.clean @@ -29,8 +29,7 @@ subdir-ymn := $(addprefix $(obj)/,$(subdir-ymn)) __clean-files := $(extra-y) $(extra-m) $(extra-) \ $(always) $(always-y) $(always-m) $(always-) $(targets) $(clean-files) \ - $(hostprogs) $(hostprogs-y) $(hostprogs-m) $(hostprogs-) $(userprogs) \ - $(hostcxxlibs-y) $(hostcxxlibs-m) + $(hostprogs) $(hostprogs-y) $(hostprogs-m) $(hostprogs-) $(userprogs) __clean-files := $(filter-out $(no-clean-files), $(__clean-files)) diff --git a/scripts/Makefile.host b/scripts/Makefile.host index c8a4a033dc3e..687ca3f309e9 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -39,7 +39,6 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE # They are linked as C++ code to the executable qconf __hostprogs := $(sort $(hostprogs)) -host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m)) # C code # Executables compiled from a single .c file @@ -61,16 +60,11 @@ host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m))) # C++ Object (.o) files compiled from .cc files host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) -# Object (.o) files used by the shared libaries -host-cxxshobjs := $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs)))) - host-csingle := $(addprefix $(obj)/,$(host-csingle)) host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) -host-cxxshlib := $(addprefix $(obj)/,$(host-cxxshlib)) -host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs)) ##### # Handle options to gcc. Support building with separate output directory @@ -136,25 +130,5 @@ quiet_cmd_host-cxxobjs = HOSTCXX $@ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE $(call if_changed_dep,host-cxxobjs) -# Compile .c file, create position independent .o file -# Note that plugin capable gcc versions can be either C or C++ based -# therefore plugin source files have to be compilable in both C and C++ mode. -# This is why a C++ compiler is invoked on a .c file. -# host-cxxshobjs -> .o -quiet_cmd_host-cxxshobjs = HOSTCXX -fPIC $@ - cmd_host-cxxshobjs = $(HOSTCXX) $(hostcxx_flags) -fPIC -c -o $@ $< -$(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE - $(call if_changed_dep,host-cxxshobjs) - -# Link a shared library, based on position independent .o files -# *.o -> .so shared library (host-cxxshlib) -quiet_cmd_host-cxxshlib = HOSTLLD -shared $@ - cmd_host-cxxshlib = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \ - $(addprefix $(obj)/, $($(target-stem)-objs)) \ - $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so) -$(host-cxxshlib): FORCE - $(call if_changed,host-cxxshlib) -$(call multi_depend, $(host-cxxshlib), .so, -objs) - -targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\ - $(host-cxxmulti) $(host-cxxobjs) $(host-cxxshlib) $(host-cxxshobjs) +targets += $(host-csingle) $(host-cmulti) $(host-cobjs) \ + $(host-cxxmulti) $(host-cxxobjs) diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index 4014ba7e2fbd..d66949bfeba4 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -1,22 +1,61 @@ # SPDX-License-Identifier: GPL-2.0 -GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin) -HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti -HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb -HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat -HOST_EXTRACXXFLAGS += -Wno-format-diag - -$(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h +$(obj)/randomize_layout_plugin.so: $(objtree)/$(obj)/randomize_layout_seed.h quiet_cmd_create_randomize_layout_seed = GENSEED $@ cmd_create_randomize_layout_seed = \ $(CONFIG_SHELL) $(srctree)/$(src)/gen-random-seed.sh $@ $(objtree)/include/generated/randomize_layout_hash.h $(objtree)/$(obj)/randomize_layout_seed.h: FORCE $(call if_changed,create_randomize_layout_seed) -targets = randomize_layout_seed.h randomize_layout_hash.h +targets += randomize_layout_seed.h randomize_layout_hash.h + +# Build rules for plugins +# +# No extra code is needed for single-file plugins. +# For multi-file plugins, use *-objs syntax to list the objects. +# +# If the plugin foo.so is compiled from foo.c and foo2.c, you can do: +# +# foo-objs := foo.o foo2.o + +always-y += $(GCC_PLUGIN) -hostcxxlibs-y := $(GCC_PLUGIN) -always-y := $(hostcxxlibs-y) +GCC_PLUGINS_DIR = $(shell $(CC) -print-file-name=plugin) -$(foreach p,$(hostcxxlibs-y:%.so=%),$(eval $(p)-objs := $(p).o)) +plugin_cxxflags = -Wp,-MMD,$(depfile) $(KBUILD_HOSTCXXFLAGS) -fPIC \ + -I $(GCC_PLUGINS_DIR)/include -I $(obj) -std=gnu++98 \ + -fno-rtti -fno-exceptions -fasynchronous-unwind-tables \ + -ggdb -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat \ + -Wno-format-diag +plugin_ldflags = -shared + +plugin-single := $(foreach m, $(GCC_PLUGIN), $(if $($(m:%.so=%-objs)),,$(m))) +plugin-multi := $(filter-out $(plugin-single), $(GCC_PLUGIN)) +plugin-objs := $(sort $(foreach m, $(plugin-multi), $($(m:%.so=%-objs)))) + +targets += $(plugin-single) $(plugin-multi) $(plugin-objs) clean-files += *.so + +plugin-single := $(addprefix $(obj)/, $(plugin-single)) +plugin-multi := $(addprefix $(obj)/, $(plugin-multi)) +plugin-objs := $(addprefix $(obj)/, $(plugin-objs)) + +quiet_cmd_plugin_cxx_so_c = HOSTCXX $@ + cmd_plugin_cxx_so_c = $(HOSTCXX) $(plugin_cxxflags) $(plugin_ldflags) -o $@ $< + +$(plugin-single): $(obj)/%.so: $(src)/%.c FORCE + $(call if_changed_dep,plugin_cxx_so_c) + +quiet_cmd_plugin_ld_so_o = HOSTLD $@ + cmd_plugin_ld_so_o = $(HOSTCXX) $(plugin_ldflags) -o $@ \ + $(addprefix $(obj)/, $($(target-stem)-objs)) + +$(plugin-multi): FORCE + $(call if_changed,plugin_ld_so_o) +$(foreach m, $(notdir $(plugin-multi)), $(eval $(obj)/$m: $(addprefix $(obj)/, $($(m:%.so=%-objs))))) + +quiet_cmd_plugin_cxx_o_c = HOSTCXX $@ + cmd_plugin_cxx_o_c = $(HOSTCXX) $(plugin_cxxflags) -c -o $@ $< + +$(plugin-objs): $(obj)/%.o: $(src)/%.c FORCE + $(call if_changed_dep,plugin_cxx_o_c) -- cgit v1.2.3-70-g09d2