diff options
Diffstat (limited to 'src/pkg/syscall/exec_bsd.go')
| -rw-r--r-- | src/pkg/syscall/exec_bsd.go | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/src/pkg/syscall/exec_bsd.go b/src/pkg/syscall/exec_bsd.go index 318cbc060..5d3d57813 100644 --- a/src/pkg/syscall/exec_bsd.go +++ b/src/pkg/syscall/exec_bsd.go @@ -39,10 +39,18 @@ func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr i int ) + // guard against side effects of shuffling fds below. + // Make sure that nextfd is beyond any currently open files so + // that we can't run the risk of overwriting any of them. fd := make([]int, len(attr.Files)) + nextfd = len(attr.Files) for i, ufd := range attr.Files { + if nextfd < int(ufd) { + nextfd = int(ufd) + } fd[i] = int(ufd) } + nextfd++ darwin := runtime.GOOS == "darwin" @@ -131,7 +139,6 @@ func forkAndExecInChild(argv0 *byte, argv, envv []*byte, chroot, dir *byte, attr // Pass 1: look for fd[i] < i and move those up above len(fd) // so that pass 2 won't stomp on an fd it needs later. - nextfd = int(len(fd)) if pipe < nextfd { _, _, err1 = RawSyscall(SYS_DUP2, uintptr(pipe), uintptr(nextfd), 0) if err1 != 0 { @@ -215,11 +222,6 @@ childerror: for { RawSyscall(SYS_EXIT, 253, 0, 0) } - - // Calling panic is not actually safe, - // but the for loop above won't break - // and this shuts up the compiler. - panic("unreached") } // Try to open a pipe with O_CLOEXEC set on both file descriptors. |