From d8d86f0f3afdf0d46a556e7925ed54c5f4dc0bbf Mon Sep 17 00:00:00 2001 From: Zach Koopmans Date: Wed, 3 Jun 2020 14:54:46 -0700 Subject: Add test for O_TRUNC b/36576592 calls out an edge case previously not supported by HostFS. HostFS is currently being removed, meaning gVisor supports this feature. Simply add the test to open_test. PiperOrigin-RevId: 314610226 --- test/syscalls/linux/open.cc | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'test/syscalls/linux') diff --git a/test/syscalls/linux/open.cc b/test/syscalls/linux/open.cc index 640fe6bfc..670c0284b 100644 --- a/test/syscalls/linux/open.cc +++ b/test/syscalls/linux/open.cc @@ -416,6 +416,29 @@ TEST_F(OpenTest, CanTruncateWriteOnlyNoReadPermission_NoRandomSave) { EXPECT_EQ(stat.st_size, 0); } +TEST_F(OpenTest, CanTruncateWithStrangePermissions) { + ASSERT_NO_ERRNO(SetCapability(CAP_DAC_OVERRIDE, false)); + ASSERT_NO_ERRNO(SetCapability(CAP_DAC_READ_SEARCH, false)); + const DisableSave ds; // Permissions are dropped. + std::string path = NewTempAbsPath(); + int fd; + // Create a file without user permissions. + EXPECT_THAT( // SAVE_BELOW + fd = open(path.c_str(), O_CREAT | O_TRUNC | O_WRONLY, 055), + SyscallSucceeds()); + EXPECT_THAT(close(fd), SyscallSucceeds()); + + // Cannot open file because we are owner and have no permissions set. + EXPECT_THAT(open(path.c_str(), O_RDONLY), SyscallFailsWithErrno(EACCES)); + + // We *can* chmod the file, because we are the owner. + EXPECT_THAT(chmod(path.c_str(), 0755), SyscallSucceeds()); + + // Now we can open the file again. + EXPECT_THAT(fd = open(path.c_str(), O_RDWR), SyscallSucceeds()); + EXPECT_THAT(close(fd), SyscallSucceeds()); +} + } // namespace } // namespace testing -- cgit v1.2.3