Add interceptors for the fts(3) API family from NetBSD

[krytarowski]

Summary

fts(3) is API to traverse a file hierarchy.
Cover this interface with interceptors.

Add a test to validate the interface reading
the number of regular files in /etc.

Based on original work by Yang Zheng.

[vitalybuka]

lib/sanitizer_common/sanitizer_common_interceptors.inc

7277

please move to the first assignment

7286

we should check access before referencing
so

for (char *const *pa = path_argv;;++pa) {
     COMMON_INTERCEPTOR_READ_RANGE(ctx, pa, sizeof(char **));
     if (!*pa)
         break;
     COMMON_INTERCEPTOR_READ_RANGE(ctx, *pa, REAL(strlen)(*pa) + 1);
   }

7300

declare ftsent here
and the same for the next

test/sanitizer_common/TestCases/NetBSD/fts.cc

28

NULL or != NULL is not needed

[krytarowski]

• apply comments from review
• general enhancements

[vitalybuka]

LGTM

lib/sanitizer_common/sanitizer_common_interceptors.inc

 
 #if SANITIZER_NETBSD
 #define clock_getres __clock_getres50
 #define clock_gettime __clock_gettime50
 #define clock_settime __clock_settime50
 #define ctime __ctime50
 #define ctime_r __ctime_r50
 #define devname __devname50
+#define fts_children __fts_children60
+#define fts_close __fts_close60
+#define fts_open __fts_open60
+#define fts_read __fts_read60
+#define fts_set __fts_set60
 #define getitimer __getitimer50
 #define getmntinfo __getmntinfo13
 #define getpwent __getpwent50
 #define getpwnam __getpwnam50
 #define getpwnam_r __getpwnam_r50
 #define getpwuid __getpwuid50
 #define getpwuid_r __getpwuid_r50
 #define getutent __getutent50

 #else
 #define INIT_NETENT
 #endif
 
 #if SANITIZER_INTERCEPT_GETMNTINFO
 INTERCEPTOR(int, getmntinfo, void **mntbufp, int flags) {
   void *ctx;
   COMMON_INTERCEPTOR_ENTER(ctx, getmntinfo, mntbufp, flags);
   int cnt = REAL(getmntinfo)(mntbufp, flags);
   if (cnt > 0 && mntbufp) {
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, mntbufp, sizeof(void *));
     if (*mntbufp)
       COMMON_INTERCEPTOR_WRITE_RANGE(ctx, *mntbufp, cnt * struct_statvfs_sz);
   }
   return cnt;
 }
 #define INIT_GETMNTINFO COMMON_INTERCEPT_FUNCTION(getmntinfo)
 #else
 #define INIT_GETMNTINFO
 #endif
 
 #if SANITIZER_INTERCEPT_MI_VECTOR_HASH
 INTERCEPTOR(void, mi_vector_hash, const void *key, SIZE_T len, u32 seed,
             u32 hashes[3]) {
   void *ctx;
   COMMON_INTERCEPTOR_ENTER(ctx, mi_vector_hash, key, len, seed, hashes);
   if (key)
     COMMON_INTERCEPTOR_READ_RANGE(ctx, key, len);
   REAL(mi_vector_hash)(key, len, seed, hashes);
   if (hashes)
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, hashes, sizeof(hashes[0]) * 3);
 }
 #define INIT_MI_VECTOR_HASH COMMON_INTERCEPT_FUNCTION(mi_vector_hash)
 #else
 #define INIT_MI_VECTOR_HASH
 #endif
 
 #if SANITIZER_INTERCEPT_SETVBUF
 INTERCEPTOR(int, setvbuf, __sanitizer_FILE *stream, char *buf, int mode,
   SIZE_T size) {
if (buf && ret > 0)
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buf, ret * struct_statvfs_sz);
   return ret;
 }
 #define INIT_GETVFSSTAT COMMON_INTERCEPT_FUNCTION(getvfsstat)
 #else
 #define INIT_GETVFSSTAT
 #endif
 
+#if SANITIZER_INTERCEPT_FTS
+INTERCEPTOR(void *, fts_open, char *const *path_argv, int options,
+            int (*compar)(void **, void **)) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, fts_open, path_argv, options, compar);
+  if (path_argv) {
+    for (char *const *pa = path_argv; ; ++pa) {
+      COMMON_INTERCEPTOR_READ_RANGE(ctx, pa, sizeof(char **));
+      if (!*pa)
+        break;
+      COMMON_INTERCEPTOR_READ_RANGE(ctx, *pa, REAL(strlen)(*pa) + 1);
+    }
+  }
+  // TODO(kamil): handle compar callback
+  void *fts = REAL(fts_open)(path_argv, options, compar);
+  if (fts)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, fts, struct_FTS_sz);
+  return fts;
+}
+
+INTERCEPTOR(void *, fts_read, void *ftsp) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, fts_read, ftsp);
+  if (ftsp)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, ftsp, struct_FTS_sz);
+  void *ftsent = REAL(fts_read)(ftsp);
+  if (ftsent)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ftsent, struct_FTSENT_sz);
+  return ftsent;
+}
+
+INTERCEPTOR(void *, fts_children, void *ftsp, int options) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, fts_children, ftsp, options);
+  if (ftsp)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, ftsp, struct_FTS_sz);
+  void *ftsent = REAL(fts_children)(ftsp, options);
+  if (ftsent)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ftsent, struct_FTSENT_sz);
+  return ftsent;
+}
+
+INTERCEPTOR(int, fts_set, void *ftsp, void *f, int options) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, fts_set, ftsp, f, options);
+  if (ftsp)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, ftsp, struct_FTS_sz);
+  if (f)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, f, struct_FTSENT_sz);
+  return REAL(fts_set)(ftsp, f, options);
+}
+
+INTERCEPTOR(int, fts_close, void *ftsp) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, fts_close, ftsp);
+  if (ftsp)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, ftsp, struct_FTS_sz);
+  return REAL(fts_close)(ftsp);
+}
+#define INIT_FTS                                                               \
+  COMMON_INTERCEPT_FUNCTION(fts_open);                                         \
+  COMMON_INTERCEPT_FUNCTION(fts_read);                                         \
+  COMMON_INTERCEPT_FUNCTION(fts_children);                                     \
+  COMMON_INTERCEPT_FUNCTION(fts_set);                                          \
+  COMMON_INTERCEPT_FUNCTION(fts_close);
+#else
+#define INIT_FTS
+#endif
+
 static void InitializeCommonInterceptors() {
   static u64 metadata_mem[sizeof(MetadataHashMap) / sizeof(u64) + 1];
   interceptor_metadata_map = new((void *)&metadata_mem) MetadataHashMap();
 
   INIT_MMAP;
   INIT_MMAP64;
   INIT_TEXTDOMAIN;
   INIT_STRLEN;
static void InitializeCommonInterceptors() {
   INIT_STRMODE;
   INIT_TTYENT;
   INIT_PROTOENT;
   INIT_NETENT;
   INIT_GETMNTINFO;
   INIT_MI_VECTOR_HASH;
   INIT_SETVBUF;
   INIT_GETVFSSTAT;
+  INIT_FTS;
 
   INIT___PRINTF_CHK;
 }

lib/sanitizer_common/sanitizer_platform_interceptors.h

 #define SANITIZER_INTERCEPT_TTYENT SI_NETBSD
 #define SANITIZER_INTERCEPT_PROTOENT SI_NETBSD
 #define SANITIZER_INTERCEPT_NETENT SI_NETBSD
 #define SANITIZER_INTERCEPT_SETVBUF (SI_NETBSD || SI_FREEBSD || \
   SI_LINUX || SI_MAC)
 #define SANITIZER_INTERCEPT_GETMNTINFO SI_NETBSD
 #define SANITIZER_INTERCEPT_MI_VECTOR_HASH SI_NETBSD
 #define SANITIZER_INTERCEPT_GETVFSSTAT SI_NETBSD
+#define SANITIZER_INTERCEPT_FTS SI_NETBSD
 
 #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H

lib/sanitizer_common/sanitizer_platform_limits_netbsd.h

 extern unsigned ucontext_t_sz;
 
 extern unsigned struct_rlimit_sz;
 extern unsigned struct_utimbuf_sz;
 extern unsigned struct_timespec_sz;
 extern unsigned struct_sembuf_sz;
 
 extern unsigned struct_kevent_sz;
+extern unsigned struct_FTS_sz;
+extern unsigned struct_FTSENT_sz;
 
 union __sanitizer_sigval {
   int sival_int;
   uptr sival_ptr;
 };
 
 struct __sanitizer_sigevent {
   int sigev_notify;

lib/sanitizer_common/sanitizer_platform_limits_netbsd.cc

 unsigned struct_sigevent_sz = sizeof(struct sigevent);
 unsigned struct_sched_param_sz = sizeof(struct sched_param);
 unsigned struct_sockaddr_sz = sizeof(struct sockaddr);
 unsigned ucontext_t_sz = sizeof(ucontext_t);
 unsigned struct_rlimit_sz = sizeof(struct rlimit);
 unsigned struct_timespec_sz = sizeof(struct timespec);
 unsigned struct_sembuf_sz = sizeof(struct sembuf);
 unsigned struct_kevent_sz = sizeof(struct kevent);
+unsigned struct_FTS_sz = sizeof(FTS);
+unsigned struct_FTSENT_sz = sizeof(FTSENT);
 unsigned struct_utimbuf_sz = sizeof(struct utimbuf);
 unsigned struct_itimerspec_sz = sizeof(struct itimerspec);
 unsigned struct_timex_sz = sizeof(struct timex);
 unsigned struct_msqid_ds_sz = sizeof(struct msqid_ds);
 unsigned struct_mq_attr_sz = sizeof(struct mq_attr);
 unsigned struct_statvfs_sz = sizeof(struct statvfs);
 unsigned struct_sigaltstack_sz = sizeof(stack_t);
 

test/sanitizer_common/TestCases/NetBSD/fts.cc

+// RUN: %clangxx -O0 -g %s -o %t && %run %t 2>&1 | FileCheck %s
+
+#include <sys/param.h>
+#include <sys/types.h>
+
+#include <sys/stat.h>
+
+#include <assert.h>
+#include <fts.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main() {
+  char *const paths[] = {(char *)"/etc", 0};
+  FTS *ftsp = fts_open(paths, FTS_LOGICAL, NULL);
+  assert(ftsp);
+
+  FTSENT *chp = fts_children(ftsp, 0);
+  assert(chp);
+
+  size_t n = 0;
+  for (FTSENT *p = fts_read(ftsp); p; p = fts_read(ftsp)) {
+    /* Skip recursively subdirectories */
+    if (p->fts_info == FTS_D && p->fts_level != FTS_ROOTLEVEL) /* pre-order */
+      fts_set(ftsp, p, FTS_SKIP);
+    else if (p->fts_info == FTS_DP) /* post-order */
+      continue;
+    else if (p->fts_info == FTS_F) /* regular file */
+      n++;
+  }
+
+  int rv = fts_close(ftsp);
+  assert(!rv);
+
+  printf("Number of files in /etc: '%zu'\n", n);
+
+  return EXIT_SUCCESS;
+
+  // CHECK: Number of files in /etc: '{{.*}}'
+}