X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fptrace.c;h=7b058a2dc66afecdaeb58877102957dff77e7d81;hb=a91eba5b9db4c09f53c8f23327915c7c75d3235f;hp=8d7d5c9c1be31058b651101503edc68028e62351;hpb=b4549a24b6194201077d0295207ec204f785fab1;p=firefly-linux-kernel-4.4.55.git

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 8d7d5c9c1be3..7b058a2dc66a 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -325,16 +325,6 @@ static int putreg(struct task_struct *child,
 		return set_flags(child, value);
 
 #ifdef CONFIG_X86_64
-	/*
-	 * Orig_ax is really just a flag with small positive and
-	 * negative values, so make sure to always sign-extend it
-	 * from 32 bits so that it works correctly regardless of
-	 * whether we come from a 32-bit environment or not.
-	 */
-	case offsetof(struct user_regs_struct, orig_ax):
-		value = (long) (s32) value;
-		break;
-
 	case offsetof(struct user_regs_struct,fs_base):
 		if (value >= TASK_SIZE_OF(child))
 			return -EIO;
@@ -1126,10 +1116,15 @@ static int putreg32(struct task_struct *child, unsigned regno, u32 value)
 
 	case offsetof(struct user32, regs.orig_eax):
 		/*
-		 * Sign-extend the value so that orig_eax = -1
-		 * causes (long)orig_ax < 0 tests to fire correctly.
+		 * A 32-bit debugger setting orig_eax means to restore
+		 * the state of the task restarting a 32-bit syscall.
+		 * Make sure we interpret the -ERESTART* codes correctly
+		 * in case the task is not actually still sitting at the
+		 * exit from a 32-bit syscall with TS_COMPAT still set.
 		 */
-		regs->orig_ax = (long) (s32) value;
+		regs->orig_ax = value;
+		if (syscall_get_nr(child, regs) >= 0)
+			task_thread_info(child)->status |= TS_COMPAT;
 		break;
 
 	case offsetof(struct user32, regs.eflags):