1 files changed, 8 insertions, 4 deletions

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 8022d3c695c0..ae7158bce4d6 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -162,12 +162,14 @@ sysenter_tracesys:
         SAVE_REST
         CLEAR_RREGS
         movq    %r9,R9(%rsp)
-        movq    $-ENOSYS,RAX(%rsp)      /* really needed? */
+        movq    $-ENOSYS,RAX(%rsp)/* ptrace can change this for a bad syscall */
         movq    %rsp,%rdi        /* &pt_regs -> arg1 */
         call    syscall_trace_enter
         LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
         RESTORE_REST
         xchgl   %ebp,%r9d
+        cmpl    $(IA32_NR_syscalls-1),%eax
+        ja      int_ret_from_sys_call /* sysenter_tracesys has set RAX(%rsp) */
         jmp     sysenter_do_call
         CFI_ENDPROC
 ENDPROC(ia32_sysenter_target)
@@ -261,13 +263,15 @@ cstar_tracesys:
         SAVE_REST
         CLEAR_RREGS
         movq %r9,R9(%rsp)
-        movq $-ENOSYS,RAX(%rsp) /* really needed? */
+        movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
         movq %rsp,%rdi        /* &pt_regs -> arg1 */
         call syscall_trace_enter
         LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
         RESTORE_REST
         xchgl %ebp,%r9d
         movl RSP-ARGOFFSET(%rsp), %r8d
+        cmpl $(IA32_NR_syscalls-1),%eax
+        ja int_ret_from_sys_call /* cstar_tracesys has set RAX(%rsp) */
         jmp cstar_do_call
 END(ia32_cstar_target)
                                 
@@ -325,7 +329,7 @@ ENTRY(ia32_syscall)
         jnz ia32_tracesys
 ia32_do_syscall:        
         cmpl $(IA32_NR_syscalls-1),%eax
-        ja  ia32_badsys
+        ja  int_ret_from_sys_call       /* ia32_tracesys has set RAX(%rsp) */
         IA32_ARG_FIXUP
         call *ia32_sys_call_table(,%rax,8) # xxx: rip relative
 ia32_sysret:
@@ -335,7 +339,7 @@ ia32_sysret:
 ia32_tracesys:                   
         SAVE_REST
         CLEAR_RREGS
-        movq $-ENOSYS,RAX(%rsp) /* really needed? */
+        movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
         movq %rsp,%rdi        /* &pt_regs -> arg1 */
         call syscall_trace_enter
         LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */