diff options
| author | Jessica Yu <jeyu@kernel.org> | 2020-09-01 18:00:16 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-17 13:47:49 +0200 |
| commit | ff37a2636464e8c4fe320d281b6ad220f14eb46a (patch) | |
| tree | 542f2954e4329395a2f272a777f4a50153900b2a /arch/arm64/kernel | |
| parent | 2423f3a7ef524d04952ddf85affb3f6264a7a6bb (diff) | |
arm64/module: set trampoline section flags regardless of CONFIG_DYNAMIC_FTRACE
[ Upstream commit e0328feda79d9681b3e3245e6e180295550c8ee9 ]
In the arm64 module linker script, the section .text.ftrace_trampoline
is specified unconditionally regardless of whether CONFIG_DYNAMIC_FTRACE
is enabled (this is simply due to the limitation that module linker
scripts are not preprocessed like the vmlinux one).
Normally, for .plt and .text.ftrace_trampoline, the section flags
present in the module binary wouldn't matter since module_frob_arch_sections()
would assign them manually anyway. However, the arm64 module loader only
sets the section flags for .text.ftrace_trampoline when CONFIG_DYNAMIC_FTRACE=y.
That's only become problematic recently due to a recent change in
binutils-2.35, where the .text.ftrace_trampoline section (along with the
.plt section) is now marked writable and executable (WAX).
We no longer allow writable and executable sections to be loaded due to
commit 5c3a7db0c7ec ("module: Harden STRICT_MODULE_RWX"), so this is
causing all modules linked with binutils-2.35 to be rejected under arm64.
Drop the IS_ENABLED(CONFIG_DYNAMIC_FTRACE) check in module_frob_arch_sections()
so that the section flags for .text.ftrace_trampoline get properly set to
SHF_EXECINSTR|SHF_ALLOC, without SHF_WRITE.
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: http://lore.kernel.org/r/20200831094651.GA16385@linux-8ccs
Link: https://lore.kernel.org/r/20200901160016.3646-1-jeyu@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/module-plts.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c index b182442b87a3..426018ebb700 100644 --- a/arch/arm64/kernel/module-plts.c +++ b/arch/arm64/kernel/module-plts.c @@ -270,8 +270,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, mod->arch.core.plt_shndx = i; else if (!strcmp(secstrings + sechdrs[i].sh_name, ".init.plt")) mod->arch.init.plt_shndx = i; - else if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE) && - !strcmp(secstrings + sechdrs[i].sh_name, + else if (!strcmp(secstrings + sechdrs[i].sh_name, ".text.ftrace_trampoline")) tramp = sechdrs + i; else if (sechdrs[i].sh_type == SHT_SYMTAB) |