| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 1 Mar 2017 11:37:18 -0800
From: tip-bot for Josh Poimboeuf <tipbot@...or.com>
To: linux-tip-commits@...r.kernel.org
Cc: torvalds@...ux-foundation.org, jpoimboe@...hat.com,
jeyu@...hat.com, linux-kernel@...r.kernel.org, mingo@...nel.org,
hpa@...or.com, tglx@...utronix.de, peterz@...radead.org
Subject: [tip:core/urgent] objtool, modules: Discard objtool annotation
sections for modules
Commit-ID: e390f9a9689a42f477a6073e2e7df530a4c1b740
Gitweb: http://git.kernel.org/tip/e390f9a9689a42f477a6073e2e7df530a4c1b740
Author: Josh Poimboeuf <jpoimboe@...hat.com>
AuthorDate: Wed, 1 Mar 2017 12:04:44 -0600
Committer: Ingo Molnar <mingo@...nel.org>
CommitDate: Wed, 1 Mar 2017 20:32:25 +0100
objtool, modules: Discard objtool annotation sections for modules
The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time. They're discarded for vmlinux but they
should also be discarded for modules.
Since this is a recurring pattern, prefix the section names with
".discard.". It's a nice convention and vmlinux.lds.h already discards
such sections.
Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.
Suggested-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@...hat.com>
Cc: Jessica Yu <jeyu@...hat.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Thomas Gleixner <tglx@...utronix.de>
Fixes: d1091c7fa3d5 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@treble
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
arch/x86/kernel/vmlinux.lds.S | 2 --
include/linux/compiler-gcc.h | 2 +-
include/linux/frame.h | 2 +-
scripts/mod/modpost.c | 1 +
scripts/module-common.lds | 5 ++++-
tools/objtool/builtin-check.c | 6 +++---
6 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index ad0118f..c74ae9c 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -345,8 +345,6 @@ SECTIONS
DISCARDS
/DISCARD/ : {
*(.eh_frame)
- *(__func_stack_frame_non_standard)
- *(__unreachable)
}
}
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index b6bb901..0efef9c 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -200,7 +200,7 @@
#ifdef CONFIG_STACK_VALIDATION
#define annotate_unreachable() ({ \
asm("%c0:\t\n" \
- ".pushsection __unreachable, \"a\"\t\n" \
+ ".pushsection .discard.unreachable\t\n" \
".long %c0b - .\t\n" \
".popsection\t\n" : : "i" (__LINE__)); \
})
diff --git a/include/linux/frame.h b/include/linux/frame.h
index e6baaba..d772c61 100644
--- a/include/linux/frame.h
+++ b/include/linux/frame.h
@@ -11,7 +11,7 @@
* For more information, see tools/objtool/Documentation/stack-validation.txt.
*/
#define STACK_FRAME_NON_STANDARD(func) \
- static void __used __section(__func_stack_frame_non_standard) \
+ static void __used __section(.discard.func_stack_frame_non_standard) \
*__func_stack_frame_non_standard_##func = func
#else /* !CONFIG_STACK_VALIDATION */
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 4dedd0d..30d752a 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -854,6 +854,7 @@ static const char *const section_white_list[] =
".cmem*", /* EZchip */
".fmt_slot*", /* EZchip */
".gnu.lto*",
+ ".discard.*",
NULL
};
diff --git a/scripts/module-common.lds b/scripts/module-common.lds
index 73a2c7d..cf7e52e 100644
--- a/scripts/module-common.lds
+++ b/scripts/module-common.lds
@@ -4,7 +4,10 @@
* combine them automatically.
*/
SECTIONS {
- /DISCARD/ : { *(.discard) }
+ /DISCARD/ : {
+ *(.discard)
+ *(.discard.*)
+ }
__ksymtab 0 : { *(SORT(___ksymtab+*)) }
__ksymtab_gpl 0 : { *(SORT(___ksymtab_gpl+*)) }
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index 5fc52ee..4cfdbb5 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -339,13 +339,13 @@ static int add_dead_ends(struct objtool_file *file)
struct instruction *insn;
bool found;
- sec = find_section_by_name(file->elf, ".rela__unreachable");
+ sec = find_section_by_name(file->elf, ".rela.discard.unreachable");
if (!sec)
return 0;
list_for_each_entry(rela, &sec->rela_list, list) {
if (rela->sym->type != STT_SECTION) {
- WARN("unexpected relocation symbol type in .rela__unreachable");
+ WARN("unexpected relocation symbol type in %s", sec->name);
return -1;
}
insn = find_insn(file, rela->sym->sec, rela->addend);
@@ -1272,7 +1272,7 @@ int cmd_check(int argc, const char **argv)
INIT_LIST_HEAD(&file.insn_list);
hash_init(file.insn_hash);
- file.whitelist = find_section_by_name(file.elf, "__func_stack_frame_non_standard");
+ file.whitelist = find_section_by_name(file.elf, ".discard.func_stack_frame_non_standard");
file.rodata = find_section_by_name(file.elf, ".rodata");
file.ignore_unreachables = false;
file.c_file = find_section_by_name(file.elf, ".comment");
Powered by blists - more mailing lists