diff options
| -rw-r--r-- | arch/x86/ia32/ia32_signal.c | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/ptrace.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/thread_info.h | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/process_32.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/process_64.c | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/signal.c | 2 |
6 files changed, 17 insertions, 6 deletions
diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index d0165c9a2932..1f5e2b0e09ff 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -203,6 +203,8 @@ static int ia32_restore_sigcontext(struct pt_regs *regs, err |= restore_xstate_sig(buf, 1); + force_iret(); + return err; } diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 74bb2e0f3030..83b874da2762 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -251,7 +251,7 @@ static inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, */ #define arch_ptrace_stop_needed(code, info) \ ({ \ - set_thread_flag(TIF_NOTIFY_RESUME); \ + force_iret(); \ false; \ }) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index ba115eb6fbcf..0abf7ab20ce2 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -260,6 +260,16 @@ static inline bool is_ia32_task(void) #endif return false; } + +/* + * Force syscall return via IRET by making it look as if there was + * some work pending. IRET is our most capable (but slowest) syscall + * return path, which is able to restore modified SS, CS and certain + * EFLAGS values that other (fast) syscall return instructions + * are not able to restore properly. + */ +#define force_iret() set_thread_flag(TIF_NOTIFY_RESUME) + #endif /* !__ASSEMBLY__ */ #ifndef __ASSEMBLY__ diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 1b9963faf4eb..26c596d1ee07 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -206,11 +206,7 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) regs->ip = new_ip; regs->sp = new_sp; regs->flags = X86_EFLAGS_IF; - /* - * force it to the iret return path by making it look as if there was - * some work pending. - */ - set_thread_flag(TIF_NOTIFY_RESUME); + force_iret(); } EXPORT_SYMBOL_GPL(start_thread); diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 97f5658290b7..da8b74598d90 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -239,6 +239,7 @@ start_thread_common(struct pt_regs *regs, unsigned long new_ip, regs->cs = _cs; regs->ss = _ss; regs->flags = X86_EFLAGS_IF; + force_iret(); } void diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index edcb862cdcae..eaa2c5e3f2cd 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -108,6 +108,8 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32)); + force_iret(); + return err; } |