From 7bcdea4d050cbe4912854a68b93494203eec8b24 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Mon, 5 Oct 2015 17:48:00 -0700 Subject: [PATCH] x86/elf/64: Clear more registers in elf_common_init() Before we start calling execve in contexts that honor the full pt_regs, we need to teach it to initialize all registers. Signed-off-by: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/65a38a9edee61a1158cfd230800c61dbd963dac5.1444091584.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/elf.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 2ee05c4f5f37..1514753fd435 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -171,11 +171,11 @@ do { \ static inline void elf_common_init(struct thread_struct *t, struct pt_regs *regs, const u16 ds) { - /* Commented-out registers are cleared in stub_execve */ - /*regs->ax = regs->bx =*/ regs->cx = regs->dx = 0; - regs->si = regs->di /*= regs->bp*/ = 0; + /* ax gets execve's return value. */ + /*regs->ax = */ regs->bx = regs->cx = regs->dx = 0; + regs->si = regs->di = regs->bp = 0; regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0; - /*regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;*/ + regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; t->fs = t->gs = 0; t->fsindex = t->gsindex = 0; t->ds = t->es = ds; -- 2.20.1