prctl: fix decoding of unrecognized commands

The use of printargs introduced by commit v4.10-179-g210a6b6 is wrong:
when the first argument is already printed, printargs cannot be called.

* prctl.c (print_prctl_args): New function.
(sys_prctl): Use it.

diff --git a/prctl.c b/prctl.c
index ae36d5bea9e5a0a7367e4e10b3749aa7235e099f..4c12bacae82ec93162b667858e9a37843f3827d6 100644 (file)
--- a/prctl.c
+++ b/prctl.c
@@ -31,6 +31,15 @@ enum {
 
 #include "xlat/cap.h"
 
+static void
+print_prctl_args(struct tcb *tcp, const unsigned int first)
+{
+       unsigned int i;
+
+       for (i = first; i < tcp->s_ent->nargs; ++i)
+               tprintf(", %#lx", tcp->u_arg[i]);
+}
+
 SYS_FUNC(prctl)
 {
        unsigned int i;
@@ -151,8 +160,7 @@ SYS_FUNC(prctl)
                                   "PR_MCE_KILL_???");
                else
                        tprintf("%#lx", tcp->u_arg[2]);
-               for (i = 3; i < tcp->s_ent->nargs; i++)
-                       tprintf(", %#lx", tcp->u_arg[i]);
+               print_prctl_args(tcp, 3);
                return RVAL_DECODED;
 
        case PR_SET_NAME:
@@ -163,8 +171,7 @@ SYS_FUNC(prctl)
        case PR_SET_MM:
                tprints(", ");
                printxval(pr_set_mm, tcp->u_arg[1], "PR_SET_MM_???");
-               for (i = 2; i < tcp->s_ent->nargs; i++)
-                       tprintf(", %#lx", tcp->u_arg[i]);
+               print_prctl_args(tcp, 2);
                return RVAL_DECODED;
 
        case PR_SET_PDEATHSIG:
@@ -194,8 +201,7 @@ SYS_FUNC(prctl)
                        print_seccomp_filter(tcp, tcp->u_arg[2]);
                        return RVAL_DECODED;
                }
-               for (i = 2; i < tcp->s_ent->nargs; i++)
-                       tprintf(", %#lx", tcp->u_arg[i]);
+               print_prctl_args(tcp, 2);
                return RVAL_DECODED;
 
        case PR_SET_SECUREBITS:
@@ -220,19 +226,22 @@ SYS_FUNC(prctl)
        case PR_SET_NO_NEW_PRIVS:
        case PR_SET_THP_DISABLE:
                tprintf(", %lu", tcp->u_arg[1]);
-               for (i = 2; i < tcp->s_ent->nargs; i++)
-                       tprintf(", %#lx", tcp->u_arg[i]);
+               print_prctl_args(tcp, 2);
                return RVAL_DECODED;
 
        case PR_GET_NO_NEW_PRIVS:
        case PR_GET_THP_DISABLE:
-               if (entering(tcp))
-                       return printargs(tcp);
+               if (entering(tcp)) {
+                       print_prctl_args(tcp, 1);
+                       return 0;
+               }
                return syserror(tcp) ? 0 : RVAL_UDECIMAL;
 
        case PR_MCE_KILL_GET:
-               if (entering(tcp))
-                       return printargs(tcp);
+               if (entering(tcp)) {
+                       print_prctl_args(tcp, 1);
+                       return 0;
+               }
                if (syserror(tcp))
                        return 0;
                tcp->auxstr = xlookup(pr_mce_kill_policy, tcp->u_rval);
@@ -241,7 +250,7 @@ SYS_FUNC(prctl)
        case PR_MPX_DISABLE_MANAGEMENT:
        case PR_MPX_ENABLE_MANAGEMENT:
        default:
-               printargs(tcp);
+               print_prctl_args(tcp, 1);
                return RVAL_DECODED;
        }
        return 0;