[PATCH] x86_64: fix single step handling for 32bit processes

From: Peter Beutner
Date: Mon Oct 24 2005 - 18:36:06 EST


Be more careful with TF handling to fix some copy protection codes in wine

patch originally for i386 by Linus, then ported to x86_64 by Andi Kleen
see: [PATCH] x86_64: Some fixes for single step handling
commit: be61bff789fe44bfb6d9282d8f7eccc860bdcfb6

But it was never applied to the ia32 emulation code which breaks some
copy-protection schemes under wine when running on x86_64.

Signed-off-by: Peter Beutner <p.beutner@xxxxxxx>

--- linux-2.6/arch/x86_64/ia32/ia32_signal.c.old 2005-10-25 00:52:29.000000000 +0200
+++ linux-2.6/arch/x86_64/ia32/ia32_signal.c 2005-10-25 00:52:59.000000000 +0200
@@ -353,7 +353,6 @@ ia32_setup_sigcontext(struct sigcontext_
struct pt_regs *regs, unsigned int mask)
{
int tmp, err = 0;
- u32 eflags;

tmp = 0;
__asm__("movl %%gs,%0" : "=r"(tmp): "0"(tmp));
@@ -378,10 +377,7 @@ ia32_setup_sigcontext(struct sigcontext_
err |= __put_user(current->thread.trap_no, &sc->trapno);
err |= __put_user(current->thread.error_code, &sc->err);
err |= __put_user((u32)regs->rip, &sc->eip);
- eflags = regs->eflags;
- if (current->ptrace & PT_PTRACED)
- eflags &= ~TF_MASK;
- err |= __put_user((u32)eflags, &sc->eflags);
+ err |= __put_user((u32)regs->eflags, &sc->eflags);
err |= __put_user((u32)regs->rsp, &sc->esp_at_signal);

tmp = save_i387_ia32(current, fpstate, regs, 0);
@@ -505,13 +501,9 @@ int ia32_setup_frame(int sig, struct k_s
regs->ss = __USER32_DS;

set_fs(USER_DS);
- if (regs->eflags & TF_MASK) {
- if (current->ptrace & PT_PTRACED) {
- ptrace_notify(SIGTRAP);
- } else {
- regs->eflags &= ~TF_MASK;
- }
- }
+ regs->eflags &= ~TF_MASK;
+ if (test_thread_flag(TIF_SINGLESTEP))
+ ptrace_notify(SIGTRAP);

#if DEBUG_SIG
printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
@@ -605,13 +597,9 @@ int ia32_setup_rt_frame(int sig, struct
regs->ss = __USER32_DS;

set_fs(USER_DS);
- if (regs->eflags & TF_MASK) {
- if (current->ptrace & PT_PTRACED) {
- ptrace_notify(SIGTRAP);
- } else {
- regs->eflags &= ~TF_MASK;
- }
- }
+ regs->eflags &= ~TF_MASK;
+ if (test_thread_flag(TIF_SINGLESTEP))
+ ptrace_notify(SIGTRAP);

#if DEBUG_SIG
printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
-
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