Support sticky bit in vfs2.

Updates #2923.

PiperOrigin-RevId: 318648128

2 files changed, 41 insertions, 17 deletions

diff --git a/test/syscalls/BUILD b/test/syscalls/BUILD
index c4fff0ac8..36c178e4a 100644
--- a/test/syscalls/BUILD
+++ b/test/syscalls/BUILD
@@ -942,6 +942,7 @@ syscall_test(
 syscall_test(
     add_overlay = True,
     test = "//test/syscalls/linux:sticky_test",
+    vfs2 = "True",
 )
 
 syscall_test(
diff --git a/test/syscalls/linux/sticky.cc b/test/syscalls/linux/sticky.cc
index 92eec0449..39f4fb801 100644
--- a/test/syscalls/linux/sticky.cc
+++ b/test/syscalls/linux/sticky.cc
@@ -40,11 +40,14 @@ namespace {
 TEST(StickyTest, StickyBitPermDenied) {
   SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SETUID)));
 
-  auto dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
-  EXPECT_THAT(chmod(dir.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
-  const FileDescriptor dirfd =
-      ASSERT_NO_ERRNO_AND_VALUE(Open(dir.path(), O_DIRECTORY));
-  ASSERT_THAT(mkdirat(dirfd.get(), "NewDir", 0755), SyscallSucceeds());
+  const TempPath parent = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  EXPECT_THAT(chmod(parent.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
+  const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateFileWith(parent.path(), "some content", 0755));
+  const TempPath dir =
+      ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirWith(parent.path(), 0755));
+  const TempPath link = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateSymlinkTo(parent.path(), file.path()));
 
   // Drop privileges and change IDs only in child thread, or else this parent
   // thread won't be able to open some log files after the test ends.
@@ -62,18 +65,26 @@ TEST(StickyTest, StickyBitPermDenied) {
         syscall(SYS_setresuid, -1, absl::GetFlag(FLAGS_scratch_uid), -1),
         SyscallSucceeds());
 
-    EXPECT_THAT(unlinkat(dirfd.get(), "NewDir", AT_REMOVEDIR),
+    std::string new_path = NewTempAbsPath();
+    EXPECT_THAT(rename(file.path().c_str(), new_path.c_str()),
                 SyscallFailsWithErrno(EPERM));
+    EXPECT_THAT(unlink(file.path().c_str()), SyscallFailsWithErrno(EPERM));
+    EXPECT_THAT(rmdir(dir.path().c_str()), SyscallFailsWithErrno(EPERM));
+    EXPECT_THAT(unlink(link.path().c_str()), SyscallFailsWithErrno(EPERM));
   });
 }
 
 TEST(StickyTest, StickyBitSameUID) {
   SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SETUID)));
 
-  auto dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
-  EXPECT_THAT(chmod(dir.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
-  std::string path = JoinPath(dir.path(), "NewDir");
-  ASSERT_THAT(mkdir(path.c_str(), 0755), SyscallSucceeds());
+  const TempPath parent = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  EXPECT_THAT(chmod(parent.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
+  const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateFileWith(parent.path(), "some content", 0755));
+  const TempPath dir =
+      ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirWith(parent.path(), 0755));
+  const TempPath link = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateSymlinkTo(parent.path(), file.path()));
 
   // Drop privileges and change IDs only in child thread, or else this parent
   // thread won't be able to open some log files after the test ends.
@@ -89,18 +100,26 @@ TEST(StickyTest, StickyBitSameUID) {
         SyscallSucceeds());
 
     // We still have the same EUID.
-    EXPECT_THAT(rmdir(path.c_str()), SyscallSucceeds());
+    std::string new_path = NewTempAbsPath();
+    EXPECT_THAT(rename(file.path().c_str(), new_path.c_str()),
+                SyscallSucceeds());
+    EXPECT_THAT(unlink(new_path.c_str()), SyscallSucceeds());
+    EXPECT_THAT(rmdir(dir.path().c_str()), SyscallSucceeds());
+    EXPECT_THAT(unlink(link.path().c_str()), SyscallSucceeds());
   });
 }
 
 TEST(StickyTest, StickyBitCapFOWNER) {
   SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SETUID)));
 
-  auto dir = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
-  EXPECT_THAT(chmod(dir.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
-  const FileDescriptor dirfd =
-      ASSERT_NO_ERRNO_AND_VALUE(Open(dir.path(), O_DIRECTORY));
-  ASSERT_THAT(mkdirat(dirfd.get(), "NewDir", 0755), SyscallSucceeds());
+  const TempPath parent = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDir());
+  EXPECT_THAT(chmod(parent.path().c_str(), 0777 | S_ISVTX), SyscallSucceeds());
+  const TempPath file = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateFileWith(parent.path(), "some content", 0755));
+  const TempPath dir =
+      ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateDirWith(parent.path(), 0755));
+  const TempPath link = ASSERT_NO_ERRNO_AND_VALUE(
+      TempPath::CreateSymlinkTo(parent.path(), file.path()));
 
   // Drop privileges and change IDs only in child thread, or else this parent
   // thread won't be able to open some log files after the test ends.
@@ -117,8 +136,12 @@ TEST(StickyTest, StickyBitCapFOWNER) {
         SyscallSucceeds());
 
     EXPECT_NO_ERRNO(SetCapability(CAP_FOWNER, true));
-    EXPECT_THAT(unlinkat(dirfd.get(), "NewDir", AT_REMOVEDIR),
+    std::string new_path = NewTempAbsPath();
+    EXPECT_THAT(rename(file.path().c_str(), new_path.c_str()),
                 SyscallSucceeds());
+    EXPECT_THAT(unlink(new_path.c_str()), SyscallSucceeds());
+    EXPECT_THAT(rmdir(dir.path().c_str()), SyscallSucceeds());
+    EXPECT_THAT(unlink(link.path().c_str()), SyscallSucceeds());
   });
 }
 }  // namespace