Add new interceptors: getttyent(3) family

[krytarowski]

Summary

getttyent, getttynam, setttyentpath - get ttys file entry

Reuse them on NetBSD.

Sponsored by <The NetBSD Foundation>

[krytarowski]

Ping?

[vitalybuka]

LGTM if you address my comments

lib/sanitizer_common/sanitizer_common_interceptors.inc

6844

struct __sanitizer_ttyent *ttyent = REAL...
here and below

6845

please no brackets here and below

6862

it does not check anything, why do you want to intercept it?
same for endttyent

7121

Could you please convert this peace into INIT_ style?
As a separate patch.
Trivial but I can't be sure that it compiles if I do it myself.

test/sanitizer_common/TestCases/NetBSD/getttyent.cc

5 ↗

(On Diff #135172)

maybe ttyent.cc is better name
same for INIT_GETTTYENT->INIT_TTYENT

[vitalybuka]

test/sanitizer_common/TestCases/NetBSD/getttyent.cc

13 ↗

(On Diff #135172)

test would be cleaner without
if (!typ) exit(1);

if it nullptr it will fail anyway at printf

45 ↗

(On Diff #135172)

Could you please combine declaration and initialization here and the rest?
struct ttyent *typ = getttyent();

[krytarowski]

lib/sanitizer_common/sanitizer_common_interceptors.inc

6862

Disable recursive interceptors.

7121

Do you mean, __libc_mutex_lock and the others bellow?

[vitalybuka]

test/sanitizer_common/TestCases/NetBSD/getttyent.cc

77 ↗

(On Diff #135172)

Maybe some checks if you print it?

[vitalybuka]

I'll make it red for consistency and promise to look again ASAP.

lib/sanitizer_common/sanitizer_platform_interceptors.h

464

Why only NETBSD?

[krytarowski]

lib/sanitizer_common/sanitizer_platform_interceptors.h

464

I can assure only NetBSD. Feel free to switch it to POSIX or other combination of OSes in a new commit.

test/sanitizer_common/TestCases/NetBSD/getttyent.cc

77 ↗

(On Diff #135172)

I was thinking about it, however this setup uses the global configuration of a system that might be (and usually is) customized. It's easier with e.g. protoent, as protocol entries aren't usually modified.

[krytarowski]

apply comments from review

[krytarowski]

• add missing changes to sanitizer_platform_limits_netbsd
• fix a typo

[krytarowski]

• drop interceptors for setttyent(3) and endttyent(3)

[vitalybuka]

lib/sanitizer_common/sanitizer_common_interceptors.inc

6844

unchanged

struct __sanitizer_ttyent *ttyent = REAL... here and below

6845

unchanged

please no brackets here and below

6862

I don't see how this helps.
Also you already removed such empty interceptors from other patches.

7121

Yes.

Do you mean, __libc_mutex_lock and the others bellow?

lib/sanitizer_common/sanitizer_platform_interceptors.h

464

I can assure only NetBSD. Feel free to switch it to POSIX or other combination of OSes in a new commit.

SGTM

test/sanitizer_common/TestCases/NetBSD/getttyent.cc

13 ↗

(On Diff #135172)

also unchanged

[krytarowski]

@vitalybuka I think you have reviewed an older snapshot. All the mentioned now issues are gone.

I've retested the interceptors without arguments and the code still works fine.

[vitalybuka]

Sorry. I am not sure how did this happen.

[krytarowski]

I will add test name to CHECK in the test, and commit all three tests.

lib/sanitizer_common/sanitizer_common_interceptors.inc

 #define INIT_STRMODE
 #endif
 
+#if SANITIZER_INTERCEPT_TTYENT
+INTERCEPTOR(struct __sanitizer_ttyent *, getttyent, void) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, getttyent);
+  struct __sanitizer_ttyent *ttyent = REAL(getttyent)();
+  if (ttyent)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ttyent, struct_ttyent_sz);
+  return ttyent;
+}
+INTERCEPTOR(struct __sanitizer_ttyent *, getttynam, char *name) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, getttynam, name);
+  if (name)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, name, REAL(strlen)(name) + 1);
+  struct __sanitizer_ttyent *ttyent = REAL(getttynam)(name);
+  if (ttyent)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ttyent, struct_ttyent_sz);
+  return ttyent;
+}
+INTERCEPTOR(int, setttyentpath, char *path) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, setttyentpath, path);
+  if (path)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, path, REAL(strlen)(path) + 1);
+  return REAL(setttyentpath)(path);
+}
+#define INIT_TTYENT \
+  COMMON_INTERCEPT_FUNCTION(getttyent); \
+  COMMON_INTERCEPT_FUNCTION(getttynam); \
+  COMMON_INTERCEPT_FUNCTION(setttyentpath)
+#else
+#define INIT_TTYENT
+#endif
+
 static void InitializeCommonInterceptors() {
   static u64 metadata_mem[sizeof(MetadataHashMap) / sizeof(u64) + 1];
   interceptor_metadata_map = new((void *)&metadata_mem) MetadataHashMap();

   INIT_DEVNAME_R;
   INIT_FGETLN;
   INIT_STRMODE;
+  INIT_TTYENT;
 
 #if SANITIZER_NETBSD
   COMMON_INTERCEPT_FUNCTION(__libc_mutex_lock);

lib/sanitizer_common/sanitizer_platform_interceptors.h

 #define SANITIZER_INTERCEPT_DEVNAME_R SI_NETBSD
 #define SANITIZER_INTERCEPT_FGETLN SI_NETBSD
 #define SANITIZER_INTERCEPT_STRMODE SI_NETBSD
+#define SANITIZER_INTERCEPT_TTYENT SI_NETBSD
 
 #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H

lib/sanitizer_common/sanitizer_platform_limits_netbsd.h

 
 extern unsigned path_max;
 
+extern int struct_ttyent_sz;
+
 extern int ptrace_pt_io;
 extern int ptrace_pt_lwpinfo;
 extern int ptrace_pt_set_event_mask;

   } ifc_ifcu;
 };
 
+struct __sanitizer_ttyent {
+  char *ty_name;
+  char *ty_getty;
+  char *ty_type;
+  int ty_status;
+  char *ty_window;
+  char *ty_comment;
+  char *ty_class;
+};
+
 #define IOC_NRBITS 8
 #define IOC_TYPEBITS 8
 #define IOC_SIZEBITS 14

lib/sanitizer_common/sanitizer_platform_limits_netbsd.cc

 #include <term.h>
 #include <termios.h>
 #include <time.h>
+#include <ttyent.h>
 #include <utime.h>
 #include <utmp.h>
 #include <utmpx.h>

 
 unsigned path_max = PATH_MAX;
 
+int struct_ttyent_sz = sizeof(struct ttyent);
+
 // ioctl arguments
 unsigned struct_altqreq_sz = sizeof(altqreq);
 unsigned struct_amr_user_ioctl_sz = sizeof(amr_user_ioctl);

test/sanitizer_common/TestCases/NetBSD/ttyent.cc

+// RUN: %clangxx -O0 -g %s -o %t && %run %t
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ttyent.h>
+
+#define STRING_OR_NULL(x) ((x) ? (x) : "null")
+
+void test1() {
+  struct ttyent *typ = getttyent();
+
+  printf("%s %s %s %d %s %s %s\n", STRING_OR_NULL(typ->ty_name),
+         STRING_OR_NULL(typ->ty_getty), STRING_OR_NULL(typ->ty_type),
+         typ->ty_status, STRING_OR_NULL(typ->ty_window),
+         STRING_OR_NULL(typ->ty_comment), STRING_OR_NULL(typ->ty_class));
+
+  endttyent();
+}
+
+void test2() {
+  struct ttyent *typ = getttynam("console");
+
+  printf("%s %s %s %d %s %s %s\n", STRING_OR_NULL(typ->ty_name),
+         STRING_OR_NULL(typ->ty_getty), STRING_OR_NULL(typ->ty_type),
+         typ->ty_status, STRING_OR_NULL(typ->ty_window),
+         STRING_OR_NULL(typ->ty_comment), STRING_OR_NULL(typ->ty_class));
+
+  endttyent();
+}
+
+void test3() {
+  if (!setttyent())
+    exit(1);
+
+  struct ttyent *typ = getttyent();
+
+  printf("%s %s %s %d %s %s %s\n", STRING_OR_NULL(typ->ty_name),
+         STRING_OR_NULL(typ->ty_getty), STRING_OR_NULL(typ->ty_type),
+         typ->ty_status, STRING_OR_NULL(typ->ty_window),
+         STRING_OR_NULL(typ->ty_comment), STRING_OR_NULL(typ->ty_class));
+
+  endttyent();
+}
+
+void test4() {
+  if (!setttyentpath(_PATH_TTYS))
+    exit(1);
+
+  struct ttyent *typ = getttyent();
+
+  printf("%s %s %s %d %s %s %s\n", STRING_OR_NULL(typ->ty_name),
+         STRING_OR_NULL(typ->ty_getty), STRING_OR_NULL(typ->ty_type),
+         typ->ty_status, STRING_OR_NULL(typ->ty_window),
+         STRING_OR_NULL(typ->ty_comment), STRING_OR_NULL(typ->ty_class));
+
+  endttyent();
+}
+
+int main(void) {
+  test1();
+  test2();
+  test3();
+  test4();
+
+  return 0;
+}