diff options
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_file.go | 9 | ||||
| -rw-r--r-- | test/syscalls/linux/sendfile.cc | 19 |
2 files changed, 25 insertions, 3 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go index 7ad0c9517..cf6fdc190 100644 --- a/pkg/sentry/syscalls/linux/sys_file.go +++ b/pkg/sentry/syscalls/linux/sys_file.go @@ -2022,7 +2022,6 @@ func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } // Setup for sending data. - var offset uint64 var n int64 var err error w := &fs.FileWriter{t, outFile} @@ -2034,14 +2033,18 @@ func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return 0, nil, syserror.ESPIPE } // Copy in the offset. + var offset int64 if _, err := t.CopyIn(offsetAddr, &offset); err != nil { return 0, nil, err } + if offset < 0 { + return 0, nil, syserror.EINVAL + } // Send data using Preadv. - r := io.NewSectionReader(&fs.FileReader{t, inFile}, int64(offset), count) + r := io.NewSectionReader(&fs.FileReader{t, inFile}, offset, count) n, err = io.Copy(w, r) // Copy out the new offset. - if _, err := t.CopyOut(offsetAddr, n+int64(offset)); err != nil { + if _, err := t.CopyOut(offsetAddr, n+offset); err != nil { return 0, nil, err } // If we don't have a provided offset. diff --git a/test/syscalls/linux/sendfile.cc b/test/syscalls/linux/sendfile.cc index 92b7b9478..15fd01ff0 100644 --- a/test/syscalls/linux/sendfile.cc +++ b/test/syscalls/linux/sendfile.cc @@ -46,6 +46,25 @@ TEST(SendFileTest, SendZeroBytes) { SyscallSucceedsWithValue(0)); } +TEST(SendFileTest, InvalidOffset) { + // Create temp files. + const TempPath in_file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); + const TempPath out_file = ASSERT_NO_ERRNO_AND_VALUE(TempPath::CreateFile()); + + // Open the input file as read only. + const FileDescriptor inf = + ASSERT_NO_ERRNO_AND_VALUE(Open(in_file.path(), O_RDONLY)); + + // Open the output file as write only. + const FileDescriptor outf = + ASSERT_NO_ERRNO_AND_VALUE(Open(out_file.path(), O_WRONLY)); + + // Send data and verify that sendfile returns the correct value. + off_t offset = -1; + EXPECT_THAT(sendfile(outf.get(), inf.get(), &offset, 0), + SyscallFailsWithErrno(EINVAL)); +} + TEST(SendFileTest, SendTrivially) { // Create temp files. constexpr char kData[] = "To be, or not to be, that is the question:"; |