compiler-rt/test/asan/TestCases/Linux/read_binary_name_regtest.c

   1 // Regression test for https://crbug.com/502974, where ASan was unable to read
   2 // the binary name because of sandbox restrictions.
   3 // This test uses seccomp-BPF to restrict the readlink() system call and makes
   4 // sure ASan is still able to
   5 // Disable symbolizing results, since this will invoke llvm-symbolizer, which
   6 // will be unable to resolve its $ORIGIN due to readlink() restriction and will
   7 // thus fail to start, causing the test to die with SIGPIPE when attempting to
   8 // talk to it.
   9 // RUN: not ls /usr/include/linux/seccomp.h || ( %clang_asan %s -o %t && ( not env ASAN_OPTIONS=symbolize=0 %run %t 2>&1 ) | FileCheck %s )
  10 // REQUIRES: shell
  11 // UNSUPPORTED: android
  12
  13 #include <errno.h>
  14 #include <stddef.h>
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <sys/prctl.h>
  18 #include <sys/syscall.h>
  19 #include <linux/filter.h>
  20 #include <linux/seccomp.h>
  21
  22 #ifndef __NR_readlink
  23 # define __NR_readlink __NR_readlinkat
  24 #endif
  25
  26 #define syscall_nr (offsetof(struct seccomp_data, nr))
  27
  28 void corrupt() {
  29   void *p = malloc(10);
  30   free(p);
  31   free(p);
  32 }
  33
  34 int main() {
  35   prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
  36
  37   struct sock_filter filter[] = {
  38     /* Grab the system call number */
  39     BPF_STMT(BPF_LD + BPF_W + BPF_ABS, syscall_nr),
  40     // If this is __NR_readlink,
  41     BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, __NR_readlink, 0, 1),
  42     // return with EPERM,
  43     BPF_STMT(BPF_RET + BPF_K, SECCOMP_RET_ERRNO | EPERM),
  44     // otherwise allow the syscall.
  45     BPF_STMT(BPF_RET + BPF_K, SECCOMP_RET_ALLOW)
  46   };
  47   struct sock_fprog prog;
  48   prog.len = (unsigned short)(sizeof(filter)/sizeof(filter[0]));
  49   prog.filter = filter;
  50
  51   int res = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
  52   if (res != 0) {
  53     fprintf(stderr, "PR_SET_SECCOMP unsupported!\n");
  54   }
  55   corrupt();
  56   // CHECK: AddressSanitizer
  57   // CHECK-NOT: reading executable name failed
  58   return 0;
  59 }