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authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-01 17:09:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-01 17:09:03 -0700
commitf594e28d805aca2c6e158cc647f133cab58a8bb4 (patch)
treebbc6044de5bc18185c0de5318fc0d2890f9a32d8
parent01463374c50e4fe75abec927fa231f8f5d701852 (diff)
parent6425392acf24b6d469932dd1b217dc7b20d6447f (diff)
downloadlwn-f594e28d805aca2c6e158cc647f133cab58a8bb4.tar.gz
lwn-f594e28d805aca2c6e158cc647f133cab58a8bb4.zip
Merge tag 'hardening-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull compiler hardening updates from Kees Cook: "These are various compiler-related hardening feature updates. Notable is the addition of an explicit limited rationale for, and deprecation schedule of, gcc-plugins. gcc-plugins: - remove support for GCC 4.9 and older (Ard Biesheuvel) - remove duplicate include in gcc-common.h (Ye Guojin) - Explicitly document purpose and deprecation schedule (Kees Cook) - Remove cyc_complexity (Kees Cook) instrumentation: - Avoid harmless Clang option under CONFIG_INIT_STACK_ALL_ZERO (Kees Cook) Clang LTO: - kallsyms: strip LTO suffixes from static functions (Nick Desaulniers)" * tag 'hardening-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: remove duplicate include in gcc-common.h gcc-plugins: Remove cyc_complexity gcc-plugins: Explicitly document purpose and deprecation schedule kallsyms: strip LTO suffixes from static functions gcc-plugins: remove support for GCC 4.9 and older hardening: Avoid harmless Clang option under CONFIG_INIT_STACK_ALL_ZERO
-rw-r--r--Documentation/kbuild/gcc-plugins.rst28
-rw-r--r--Makefile6
-rw-r--r--kernel/kallsyms.c46
-rw-r--r--scripts/Makefile.gcc-plugins2
-rw-r--r--scripts/gcc-plugins/Kconfig20
-rw-r--r--scripts/gcc-plugins/cyc_complexity_plugin.c69
-rw-r--r--scripts/gcc-plugins/gcc-common.h132
-rw-r--r--scripts/gcc-plugins/gcc-generate-gimple-pass.h19
-rw-r--r--scripts/gcc-plugins/gcc-generate-ipa-pass.h19
-rw-r--r--scripts/gcc-plugins/gcc-generate-rtl-pass.h19
-rw-r--r--scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h19
-rw-r--r--scripts/gcc-plugins/structleak_plugin.c2
-rw-r--r--security/Kconfig.hardening14
13 files changed, 75 insertions, 320 deletions
diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst
index 3349966f213d..0ba76719f1b9 100644
--- a/Documentation/kbuild/gcc-plugins.rst
+++ b/Documentation/kbuild/gcc-plugins.rst
@@ -32,6 +32,32 @@ This infrastructure was ported from grsecurity [6]_ and PaX [7]_.
.. [7] https://pax.grsecurity.net/
+Purpose
+=======
+
+GCC plugins are designed to provide a place to experiment with potential
+compiler features that are neither in GCC nor Clang upstream. Once
+their utility is proven, the goal is to upstream the feature into GCC
+(and Clang), and then to finally remove them from the kernel once the
+feature is available in all supported versions of GCC.
+
+Specifically, new plugins should implement only features that have no
+upstream compiler support (in either GCC or Clang).
+
+When a feature exists in Clang but not GCC, effort should be made to
+bring the feature to upstream GCC (rather than just as a kernel-specific
+GCC plugin), so the entire ecosystem can benefit from it.
+
+Similarly, even if a feature provided by a GCC plugin does *not* exist
+in Clang, but the feature is proven to be useful, effort should be spent
+to upstream the feature to GCC (and Clang).
+
+After a feature is available in upstream GCC, the plugin will be made
+unbuildable for the corresponding GCC version (and later). Once all
+kernel-supported versions of GCC provide the feature, the plugin will
+be removed from the kernel.
+
+
Files
=====
@@ -70,7 +96,6 @@ Enable the GCC plugin infrastructure and some plugin(s) you want to use
in the kernel config::
CONFIG_GCC_PLUGINS=y
- CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=y
CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y
...
@@ -89,4 +114,3 @@ The GCC plugins are in scripts/gcc-plugins/. You need to put plugin source files
right under scripts/gcc-plugins/. Creating subdirectories is not supported.
It must be added to scripts/gcc-plugins/Makefile, scripts/Makefile.gcc-plugins
and a relevant Kconfig file.
-See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin.
diff --git a/Makefile b/Makefile
index a5231635ed43..d6520b797768 100644
--- a/Makefile
+++ b/Makefile
@@ -831,12 +831,12 @@ endif
# Initialize all stack variables with a zero value.
ifdef CONFIG_INIT_STACK_ALL_ZERO
-# Future support for zero initialization is still being debated, see
-# https://bugs.llvm.org/show_bug.cgi?id=45497. These flags are subject to being
-# renamed or dropped.
KBUILD_CFLAGS += -ftrivial-auto-var-init=zero
+ifdef CONFIG_CC_IS_CLANG
+# https://bugs.llvm.org/show_bug.cgi?id=45497
KBUILD_CFLAGS += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
endif
+endif
# While VLAs have been removed, GCC produces unreachable stack probes
# for the randomize_kstack_offset feature. Disable it for all compilers.
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 0ba87982d017..3011bc33a5ba 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -164,26 +164,46 @@ static unsigned long kallsyms_sym_address(int idx)
return kallsyms_relative_base - 1 - kallsyms_offsets[idx];
}
-#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_LTO_CLANG_THIN)
-/*
- * LLVM appends a hash to static function names when ThinLTO and CFI are
- * both enabled, i.e. foo() becomes foo$707af9a22804d33c81801f27dcfe489b.
- * This causes confusion and potentially breaks user space tools, so we
- * strip the suffix from expanded symbol names.
- */
-static inline bool cleanup_symbol_name(char *s)
+static bool cleanup_symbol_name(char *s)
{
char *res;
+ if (!IS_ENABLED(CONFIG_LTO_CLANG))
+ return false;
+
+ /*
+ * LLVM appends various suffixes for local functions and variables that
+ * must be promoted to global scope as part of LTO. This can break
+ * hooking of static functions with kprobes. '.' is not a valid
+ * character in an identifier in C. Suffixes observed:
+ * - foo.llvm.[0-9a-f]+
+ * - foo.[0-9a-f]+
+ * - foo.[0-9a-f]+.cfi_jt
+ */
+ res = strchr(s, '.');
+ if (res) {
+ *res = '\0';
+ return true;
+ }
+
+ if (!IS_ENABLED(CONFIG_CFI_CLANG) ||
+ !IS_ENABLED(CONFIG_LTO_CLANG_THIN) ||
+ CONFIG_CLANG_VERSION >= 130000)
+ return false;
+
+ /*
+ * Prior to LLVM 13, the following suffixes were observed when thinLTO
+ * and CFI are both enabled:
+ * - foo$[0-9]+
+ */
res = strrchr(s, '$');
- if (res)
+ if (res) {
*res = '\0';
+ return true;
+ }
- return res != NULL;
+ return false;
}
-#else
-static inline bool cleanup_symbol_name(char *s) { return false; }
-#endif
/* Lookup the address for this symbol. Returns 0 if not found. */
unsigned long kallsyms_lookup_name(const char *name)
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
index 4aad28480035..1d16ca1b78c9 100644
--- a/scripts/Makefile.gcc-plugins
+++ b/scripts/Makefile.gcc-plugins
@@ -1,7 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
-gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so
-
gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += latent_entropy_plugin.so
gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) \
+= -DLATENT_ENTROPY_PLUGIN
diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
index ab9eb4cbe33a..51d81c3f03d6 100644
--- a/scripts/gcc-plugins/Kconfig
+++ b/scripts/gcc-plugins/Kconfig
@@ -19,24 +19,10 @@ menuconfig GCC_PLUGINS
if GCC_PLUGINS
-config GCC_PLUGIN_CYC_COMPLEXITY
- bool "Compute the cyclomatic complexity of a function" if EXPERT
- depends on !COMPILE_TEST # too noisy
- help
- The complexity M of a function's control flow graph is defined as:
- M = E - N + 2P
- where
-
- E = the number of edges
- N = the number of nodes
- P = the number of connected components (exit nodes).
-
- Enabling this plugin reports the complexity to stderr during the
- build. It mainly serves as a simple example of how to create a
- gcc plugin for the kernel.
-
config GCC_PLUGIN_SANCOV
bool
+ # Plugin can be removed once the kernel only supports GCC 6+
+ depends on !CC_HAS_SANCOV_TRACE_PC
help
This plugin inserts a __sanitizer_cov_trace_pc() call at the start of
basic blocks. It supports all gcc versions with plugin support (from
@@ -83,8 +69,6 @@ config GCC_PLUGIN_RANDSTRUCT
the existing seed and will be removed by a make mrproper or
make distclean.
- Note that the implementation requires gcc 4.7 or newer.
-
This plugin was ported from grsecurity/PaX. More information at:
* https://grsecurity.net/
* https://pax.grsecurity.net/
diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c
deleted file mode 100644
index 73124c2b3edd..000000000000
--- a/scripts/gcc-plugins/cyc_complexity_plugin.c
+++ /dev/null
@@ -1,69 +0,0 @@
-/*
- * Copyright 2011-2016 by Emese Revfy <re.emese@gmail.com>
- * Licensed under the GPL v2, or (at your option) v3
- *
- * Homepage:
- * https://github.com/ephox-gcc-plugins/cyclomatic_complexity
- *
- * https://en.wikipedia.org/wiki/Cyclomatic_complexity
- * The complexity M is then defined as:
- * M = E - N + 2P
- * where
- *
- * E = the number of edges of the graph
- * N = the number of nodes of the graph
- * P = the number of connected components (exit nodes).
- *
- * Usage (4.5 - 5):
- * $ make clean; make run
- */
-
-#include "gcc-common.h"
-
-__visible int plugin_is_GPL_compatible;
-
-static struct plugin_info cyc_complexity_plugin_info = {
- .version = "20160225",
- .help = "Cyclomatic Complexity\n",
-};
-
-static unsigned int cyc_complexity_execute(void)
-{
- int complexity;
- expanded_location xloc;
-
- /* M = E - N + 2P */
- complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2;
-
- xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl));
- fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity,
- xloc.file, DECL_NAME_POINTER(current_function_decl));
-
- return 0;
-}
-
-#define PASS_NAME cyc_complexity
-
-#define NO_GATE
-#define TODO_FLAGS_FINISH TODO_dump_func
-
-#include "gcc-generate-gimple-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;
-
- PASS_INFO(cyc_complexity, "ssa", 1, PASS_POS_INSERT_AFTER);
-
- if (!plugin_default_version_check(version, &gcc_version)) {
- error(G_("incompatible gcc/plugin versions"));
- return 1;
- }
-
- register_callback(plugin_name, PLUGIN_INFO, NULL,
- &cyc_complexity_plugin_info);
- register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL,
- &cyc_complexity_pass_info);
-
- return 0;
-}
diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h
index 0c087614fc3e..9a1895747b15 100644
--- a/scripts/gcc-plugins/gcc-common.h
+++ b/scripts/gcc-plugins/gcc-common.h
@@ -27,9 +27,7 @@
#include "except.h"
#include "function.h"
#include "toplev.h"
-#if BUILDING_GCC_VERSION >= 5000
#include "expr.h"
-#endif
#include "basic-block.h"
#include "intl.h"
#include "ggc.h"
@@ -39,11 +37,7 @@
#include "params.h"
#endif
-#if BUILDING_GCC_VERSION <= 4009
-#include "pointer-set.h"
-#else
#include "hash-map.h"
-#endif
#if BUILDING_GCC_VERSION >= 7000
#include "memmodel.h"
@@ -92,16 +86,13 @@
#include "stmt.h"
#include "gimplify.h"
#include "gimple.h"
-#include "tree-ssa-operands.h"
#include "tree-phinodes.h"
#include "tree-cfg.h"
#include "gimple-iterator.h"
#include "gimple-ssa.h"
#include "ssa-iterators.h"
-#if BUILDING_GCC_VERSION >= 5000
#include "builtins.h"
-#endif
/* missing from basic_block.h... */
void debug_dominance_info(enum cdi_direction dir);
@@ -152,125 +143,6 @@ struct register_pass_info NAME##_pass_info = { \
#define TODO_dump_func 0
#define TODO_dump_cgraph 0
-#if BUILDING_GCC_VERSION <= 4009
-#define TODO_verify_il 0
-#define AVAIL_INTERPOSABLE AVAIL_OVERWRITABLE
-
-#define section_name_prefix LTO_SECTION_NAME_PREFIX
-#define fatal_error(loc, gmsgid, ...) fatal_error((gmsgid), __VA_ARGS__)
-
-rtx emit_move_insn(rtx x, rtx y);
-
-typedef struct rtx_def rtx_insn;
-
-static inline const char *get_decl_section_name(const_tree decl)
-{
- if (DECL_SECTION_NAME(decl) == NULL_TREE)
- return NULL;
-
- return TREE_STRING_POINTER(DECL_SECTION_NAME(decl));
-}
-
-static inline void set_decl_section_name(tree node, const char *value)
-{
- if (value)
- DECL_SECTION_NAME(node) = build_string(strlen(value) + 1, value);
- else
- DECL_SECTION_NAME(node) = NULL;
-}
-#endif
-
-#if BUILDING_GCC_VERSION == 4009
-typedef struct gimple_statement_asm gasm;
-typedef struct gimple_statement_base gassign;
-typedef struct gimple_statement_call gcall;
-typedef struct gimple_statement_base gcond;
-typedef struct gimple_statement_base gdebug;
-typedef struct gimple_statement_base ggoto;
-typedef struct gimple_statement_phi gphi;
-typedef struct gimple_statement_base greturn;
-
-static inline gasm *as_a_gasm(gimple stmt)
-{
- return as_a<gasm>(stmt);
-}
-
-static inline const gasm *as_a_const_gasm(const_gimple stmt)
-{
- return as_a<const gasm>(stmt);
-}
-
-static inline gassign *as_a_gassign(gimple stmt)
-{
- return stmt;
-}
-
-static inline const gassign *as_a_const_gassign(const_gimple stmt)
-{
- return stmt;
-}
-
-static inline gcall *as_a_gcall(gimple stmt)
-{
- return as_a<gcall>(stmt);
-}
-
-static inline const gcall *as_a_const_gcall(const_gimple stmt)
-{
- return as_a<const gcall>(stmt);
-}
-
-static inline gcond *as_a_gcond(gimple stmt)
-{
- return stmt;
-}
-
-static inline const gcond *as_a_const_gcond(const_gimple stmt)
-{
- return stmt;
-}
-
-static inline gdebug *as_a_gdebug(gimple stmt)
-{
- return stmt;
-}
-
-static inline const gdebug *as_a_const_gdebug(const_gimple stmt)
-{
- return stmt;
-}
-
-static inline ggoto *as_a_ggoto(gimple stmt)
-{
- return stmt;
-}
-
-static inline const ggoto *as_a_const_ggoto(const_gimple stmt)
-{
- return stmt;
-}
-
-static inline gphi *as_a_gphi(gimple stmt)
-{
- return as_a<gphi>(stmt);
-}
-
-static inline const gphi *as_a_const_gphi(const_gimple stmt)
-{
- return as_a<const gphi>(stmt);
-}
-
-static inline greturn *as_a_greturn(gimple stmt)
-{
- return stmt;
-}
-
-static inline const greturn *as_a_const_greturn(const_gimple stmt)
-{
- return stmt;
-}
-#endif
-
#define TODO_ggc_collect 0
#define NODE_SYMBOL(node) (node)
#define NODE_DECL(node) (node)->decl
@@ -282,7 +154,7 @@ static inline opt_pass *get_pass_for_id(int id)
return g->get_passes()->get_pass_for_id(id);
}
-#if BUILDING_GCC_VERSION >= 5000 && BUILDING_GCC_VERSION < 6000
+#if BUILDING_GCC_VERSION < 6000
/* gimple related */
template <>
template <>
@@ -292,7 +164,6 @@ inline bool is_a_helper<const gassign *>::test(const_gimple gs)
}
#endif
-#if BUILDING_GCC_VERSION >= 5000
#define TODO_verify_ssa TODO_verify_il
#define TODO_verify_flow TODO_verify_il
#define TODO_verify_stmts TODO_verify_il
@@ -533,7 +404,6 @@ static inline void ipa_remove_stmt_references(symtab_node *referring_node, gimpl
{
referring_node->remove_stmt_references(stmt);
}
-#endif
#if BUILDING_GCC_VERSION < 6000
#define get_inner_reference(exp, pbitsize, pbitpos, poffset, pmode, punsignedp, preversep, pvolatilep, keep_aligning) \
diff --git a/scripts/gcc-plugins/gcc-generate-gimple-pass.h b/scripts/gcc-plugins/gcc-generate-gimple-pass.h
index 51780828734e..503c07496396 100644
--- a/scripts/gcc-plugins/gcc-generate-gimple-pass.h
+++ b/scripts/gcc-plugins/gcc-generate-gimple-pass.h
@@ -78,17 +78,6 @@ static const pass_data _PASS_NAME_PASS_DATA = {
.type = GIMPLE_PASS,
.name = _PASS_NAME_NAME,
.optinfo_flags = OPTGROUP_NONE,
-#if BUILDING_GCC_VERSION >= 5000
-#elif BUILDING_GCC_VERSION == 4009
- .has_gate = _HAS_GATE,
- .has_execute = _HAS_EXECUTE,
-#else
- .gate = _GATE,
- .execute = _EXECUTE,
- .sub = NULL,
- .next = NULL,
- .static_pass_number = 0,
-#endif
.tv_id = TV_NONE,
.properties_required = PROPERTIES_REQUIRED,
.properties_provided = PROPERTIES_PROVIDED,
@@ -102,21 +91,13 @@ public:
_PASS_NAME_PASS() : gimple_opt_pass(_PASS_NAME_PASS_DATA, g) {}
#ifndef NO_GATE
-#if BUILDING_GCC_VERSION >= 5000
virtual bool gate(function *) { return _GATE(); }
-#else
- virtual bool gate(void) { return _GATE(); }
-#endif
#endif
virtual opt_pass * clone () { return new _PASS_NAME_PASS(); }
#ifndef NO_EXECUTE
-#if BUILDING_GCC_VERSION >= 5000
virtual unsigned int execute(function *) { return _EXECUTE(); }
-#else
- virtual unsigned int execute(void) { return _EXECUTE(); }
-#endif
};
}
diff --git a/scripts/gcc-plugins/gcc-generate-ipa-pass.h b/scripts/gcc-plugins/gcc-generate-ipa-pass.h
index c34ffec035bf..1e7f064e8f6e 100644
--- a/scripts/gcc-plugins/gcc-generate-ipa-pass.h
+++ b/scripts/gcc-plugins/gcc-generate-ipa-pass.h
@@ -146,17 +146,6 @@ static const pass_data _PASS_NAME_PASS_DATA = {
.type = IPA_PASS,
.name = _PASS_NAME_NAME,
.optinfo_flags = OPTGROUP_NONE,
-#if BUILDING_GCC_VERSION >= 5000
-#elif BUILDING_GCC_VERSION == 4009
- .has_gate = _HAS_GATE,
- .has_execute = _HAS_EXECUTE,
-#else
- .gate = _GATE,
- .execute = _EXECUTE,
- .sub = NULL,
- .next = NULL,
- .static_pass_number = 0,
-#endif
.tv_id = TV_NONE,
.properties_required = PROPERTIES_REQUIRED,
.properties_provided = PROPERTIES_PROVIDED,
@@ -180,20 +169,12 @@ public:
_VARIABLE_TRANSFORM) {}
#ifndef NO_GATE
-#if BUILDING_GCC_VERSION >= 5000
virtual bool gate(function *) { return _GATE(); }
-#else
- virtual bool gate(void) { return _GATE(); }
-#endif
virtual opt_pass *clone() { return new _PASS_NAME_PASS(); }
#ifndef NO_EXECUTE
-#if BUILDING_GCC_VERSION >= 5000
virtual unsigned int execute(function *) { return _EXECUTE(); }
-#else
- virtual unsigned int execute(void) { return _EXECUTE(); }
-#endif
#endif
};
}
diff --git a/scripts/gcc-plugins/gcc-generate-rtl-pass.h b/scripts/gcc-plugins/gcc-generate-rtl-pass.h
index d14614f4b139..7cd46e8d5049 100644
--- a/scripts/gcc-plugins/gcc-generate-rtl-pass.h
+++ b/scripts/gcc-plugins/gcc-generate-rtl-pass.h
@@ -78,17 +78,6 @@ static const pass_data _PASS_NAME_PASS_DATA = {
.type = RTL_PASS,
.name = _PASS_NAME_NAME,
.optinfo_flags = OPTGROUP_NONE,
-#if BUILDING_GCC_VERSION >= 5000
-#elif BUILDING_GCC_VERSION == 4009
- .has_gate = _HAS_GATE,
- .has_execute = _HAS_EXECUTE,
-#else
- .gate = _GATE,
- .execute = _EXECUTE,
- .sub = NULL,
- .next = NULL,
- .static_pass_number = 0,
-#endif
.tv_id = TV_NONE,
.properties_required = PROPERTIES_REQUIRED,
.properties_provided = PROPERTIES_PROVIDED,
@@ -102,21 +91,13 @@ public:
_PASS_NAME_PASS() : rtl_opt_pass(_PASS_NAME_PASS_DATA, g) {}
#ifndef NO_GATE
-#if BUILDING_GCC_VERSION >= 5000
virtual bool gate(function *) { return _GATE(); }
-#else
- virtual bool gate(void) { return _GATE(); }
-#endif
#endif
virtual opt_pass *clone() { return new _PASS_NAME_PASS(); }
#ifndef NO_EXECUTE
-#if BUILDING_GCC_VERSION >= 5000
virtual unsigned int execute(function *) { return _EXECUTE(); }
-#else
- virtual unsigned int execute(void) { return _EXECUTE(); }
-#endif
#endif
};
}
diff --git a/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h b/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h
index ef6f4c2cb6fa..33093ccc947a 100644
--- a/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h
+++ b/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h
@@ -78,17 +78,6 @@ static const pass_data _PASS_NAME_PASS_DATA = {
.type = SIMPLE_IPA_PASS,
.name = _PASS_NAME_NAME,
.optinfo_flags = OPTGROUP_NONE,
-#if BUILDING_GCC_VERSION >= 5000
-#elif BUILDING_GCC_VERSION == 4009
- .has_gate = _HAS_GATE,
- .has_execute = _HAS_EXECUTE,
-#else
- .gate = _GATE,
- .execute = _EXECUTE,
- .sub = NULL,
- .next = NULL,
- .static_pass_number = 0,
-#endif
.tv_id = TV_NONE,
.properties_required = PROPERTIES_REQUIRED,
.properties_provided = PROPERTIES_PROVIDED,
@@ -102,21 +91,13 @@ public:
_PASS_NAME_PASS() : simple_ipa_opt_pass(_PASS_NAME_PASS_DATA, g) {}
#ifndef NO_GATE
-#if BUILDING_GCC_VERSION >= 5000
virtual bool gate(function *) { return _GATE(); }
-#else
- virtual bool gate(void) { return _GATE(); }
-#endif
#endif
virtual opt_pass *clone() { return new _PASS_NAME_PASS(); }
#ifndef NO_EXECUTE
-#if BUILDING_GCC_VERSION >= 5000
virtual unsigned int execute(function *) { return _EXECUTE(); }
-#else
- virtual unsigned int execute(void) { return _EXECUTE(); }
-#endif
#endif
};
}
diff --git a/scripts/gcc-plugins/structleak_plugin.c b/scripts/gcc-plugins/structleak_plugin.c
index d7190e443a14..74e319288389 100644
--- a/scripts/gcc-plugins/structleak_plugin.c
+++ b/scripts/gcc-plugins/structleak_plugin.c
@@ -103,10 +103,8 @@ static void finish_type(void *event_data, void *data)
if (type == NULL_TREE || type == error_mark_node)
return;
-#if BUILDING_GCC_VERSION >= 5000
if (TREE_CODE(type) == ENUMERAL_TYPE)
return;
-#endif
if (TYPE_USERSPACE(type))
return;
diff --git a/security/Kconfig.hardening b/security/Kconfig.hardening
index 90cbaff86e13..d051f8ceefdd 100644
--- a/security/Kconfig.hardening
+++ b/security/Kconfig.hardening
@@ -23,13 +23,16 @@ config CC_HAS_AUTO_VAR_INIT_PATTERN
def_bool $(cc-option,-ftrivial-auto-var-init=pattern)
config CC_HAS_AUTO_VAR_INIT_ZERO
+ # GCC ignores the -enable flag, so we can test for the feature with
+ # a single invocation using the flag, but drop it as appropriate in
+ # the Makefile, depending on the presence of Clang.
def_bool $(cc-option,-ftrivial-auto-var-init=zero -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang)
choice
prompt "Initialize kernel stack variables at function entry"
default GCC_PLUGIN_STRUCTLEAK_BYREF_ALL if COMPILE_TEST && GCC_PLUGINS
default INIT_STACK_ALL_PATTERN if COMPILE_TEST && CC_HAS_AUTO_VAR_INIT_PATTERN
- default INIT_STACK_ALL_ZERO if CC_HAS_AUTO_VAR_INIT_PATTERN
+ default INIT_STACK_ALL_ZERO if CC_HAS_AUTO_VAR_INIT_ZERO
default INIT_STACK_NONE
help
This option enables initialization of stack variables at
@@ -53,7 +56,8 @@ choice
config GCC_PLUGIN_STRUCTLEAK_USER
bool "zero-init structs marked for userspace (weak)"
- depends on GCC_PLUGINS
+ # Plugin can be removed once the kernel only supports GCC 12+
+ depends on GCC_PLUGINS && !CC_HAS_AUTO_VAR_INIT_ZERO
select GCC_PLUGIN_STRUCTLEAK
help
Zero-initialize any structures on the stack containing
@@ -64,7 +68,8 @@ choice
config GCC_PLUGIN_STRUCTLEAK_BYREF
bool "zero-init structs passed by reference (strong)"
- depends on GCC_PLUGINS
+ # Plugin can be removed once the kernel only supports GCC 12+
+ depends on GCC_PLUGINS && !CC_HAS_AUTO_VAR_INIT_ZERO
depends on !(KASAN && KASAN_STACK)
select GCC_PLUGIN_STRUCTLEAK
help
@@ -82,7 +87,8 @@ choice
config GCC_PLUGIN_STRUCTLEAK_BYREF_ALL
bool "zero-init everything passed by reference (very strong)"
- depends on GCC_PLUGINS
+ # Plugin can be removed once the kernel only supports GCC 12+
+ depends on GCC_PLUGINS && !CC_HAS_AUTO_VAR_INIT_ZERO
depends on !(KASAN && KASAN_STACK)
select GCC_PLUGIN_STRUCTLEAK
help