Changeset 3320Tweet

Timestamp:

Nov 8, 2008, 1:35:26 AM (14 years ago)

Author:

Pascal Terjan

Message:

• Fix passing of env to execve syscall

File:

• neercs/trunk/src/mytrace.c (modified) (6 diffs)

neercs/trunk/src/mytrace.c

@@ -330 +330 @@
 #if defined USE_GRAB
     struct user_regs_struct regs;
-    char *env;
+    char *env, *p;
+    long p2, envaddr, argvaddr, envptraddr;
     char envpath[PATH_MAX+1];
-    ssize_t envsize = 32*1024;
-    int ret, fd, l;
+    ssize_t envsize = 16*1024;
+    int ret, fd, l, l2;
+    char *newargv[] = { NULL };
     ssize_t r;
+
+    ptrace(PTRACE_SETOPTIONS, t->pid, NULL, PTRACE_O_TRACEEXEC);
 
     if(ptrace(PTRACE_GETREGS, t->pid, NULL, &regs) < 0)
@@ -342 +346 @@
     }
 
+    debug("PTRACE_GETREGS done");
     env = malloc(envsize);
     if (!env)
@@ -367 +372 @@
             return -1;
     }
+    envsize = r;
     l = strlen(command)+1;
-    memcpy_into_target(t, regs.RSP, command, l);
-    memcpy_into_target(t, regs.RSP+l, env, envsize);
+    l2 = sizeof(char *);
+    p2 = regs.RSP;
+    memcpy_into_target(t, p2, command, l);
+    p2 += l;
+    argvaddr = p2;
+    memcpy_into_target(t, p2, (char *)&regs.RSP, l2);
+    p2 += l2;
+    memcpy_into_target(t, p2, (char *)&newargv, l2);
+    p2 += l2;
+    memcpy_into_target(t, p2, env, envsize);
+    envaddr = p2;
+    p2 += envsize;
+    envptraddr = p2;
+    p = env;
+    while (p < env+envsize)
+    {
+        long diffp = p - env + envaddr;
+        memcpy_into_target(t, p2, (char *)&diffp, l2);
+        p2 += l2;
+        p += strlen(p)+1;
+    }
+    memcpy_into_target(t, p2, (char *)&newargv, l2);
     free(env);
-    ret = remote_syscall(t, MYCALL_EXECVE, regs.RSP, 0, regs.RSP+l);
+    ret = remote_syscall(t, MYCALL_EXECVE, regs.RSP, argvaddr, envptraddr);
 
     if(ret < 0)
@@ -479 +505 @@
     }
 
-    debug("remote syscall %s(%lu, %lu, %lu)",
+    debug("remote syscall %s(0x%lx, 0x%lx, 0x%lx)",
           syscallnames[call], arg1, arg2, arg3);
-
-    print_registers(t->pid);
 
 #if defined __x86_64__
@@ -499 +523 @@
 
         oinst = ptrace(PTRACE_PEEKTEXT, t->pid, oldregs.RIP - 2, 0) & 0xffff;
-        fprintf(stderr, "%lx\n", oinst);
 
 #if defined __x86_64__
@@ -597 +620 @@
             /* The process is about to exit, don't do anything else */
             return 0;
+        case PTRACE_EVENT_EXEC:
+            debug("PTRACE_EVENT_EXEC");
+            return 0;
         }