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| author |   Gabriel Krisman Bertazi <krisman@collabora.com> | 2020-11-27 14:32:32 -0500 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2020-12-02 10:32:16 +0100 |
| commit | c5c878125ad5aca199dfc10b1af4010165aaa596 (patch) | |
| tree | f389ef222bb9189a987d5d64bb924d5f241f792f /arch/x86/include/asm/elf.h | |
| parent | MAINTAINERS: Add entry for common entry code (diff) | |
| download | linux-dev-c5c878125ad5aca199dfc10b1af4010165aaa596.tar.xz linux-dev-c5c878125ad5aca199dfc10b1af4010165aaa596.zip | |
x86: vdso: Expose sigreturn address on vdso to the kernel
Syscall user redirection requires the signal trampoline code to not be
captured, in order to support returning with a locked selector while
avoiding recursion back into the signal handler. For ia-32, which has
the trampoline in the vDSO, expose the entry points to the kernel, such
that it can avoid dispatching syscalls from that region to userspace.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20201127193238.821364-2-krisman@collabora.com
Diffstat (limited to 'arch/x86/include/asm/elf.h')
| -rw-r--r-- | arch/x86/include/asm/elf.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 44a9b9940535..66bdfe838d61 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -388,6 +388,8 @@ extern int compat_arch_setup_additional_pages(struct linux_binprm *bprm, compat_arch_setup_additional_pages(bprm, interpreter, \ (ex->e_machine == EM_X86_64)) +extern bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs); + /* Do not change the values. See get_align_mask() */ enum align_flags { ALIGN_VA_32 = BIT(0), |