Mercurial > hg > octave-lojdl > gnulib-hg
changeset 12132:8e0dac113023
openat: avoid using wrong fd
Detected by a Solaris failure on:
int fd = dup (0);
close (fd);
mkdirat (fd, "dir", 0700);
which created "./dir" instead of failing with EBADF.
* lib/openat.c (openat_permissive): Reject user's fd if saving the
working directory chooses same fd.
* lib/at-func.c (AT_FUNC_NAME): Likewise.
Signed-off-by: Eric Blake <ebb9@byu.net>
| author | Eric Blake <ebb9@byu.net> |
|---|---|
| date | Wed, 07 Oct 2009 06:56:52 -0600 |
| parents | 3e62859ad66f |
| children | 799664c0f270 |
| files | ChangeLog lib/at-func.c lib/openat.c |
| diffstat | 3 files changed, 23 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,10 @@ 2009-10-07 Eric Blake <ebb9@byu.net> + openat: avoid using wrong fd + * lib/openat.c (openat_permissive): Reject user's fd if saving the + working directory chooses same fd. + * lib/at-func.c (AT_FUNC_NAME): Likewise. + mkdir, mkdirat: fix cygwin 1.5.x bug * lib/mkdir.c (rpl_mkdir) [FUNC_MKDIR_DOT_BUG]: Work around bug. * m4/mkdir-slash.m4 (gl_FUNC_MKDIR_TRAILING_SLASH): Move...
--- a/lib/at-func.c +++ b/lib/at-func.c @@ -89,6 +89,15 @@ if (save_cwd (&saved_cwd) != 0) openat_save_fail (errno); + if (0 <= fd && fd == saved_cwd.desc) + { + /* If saving the working directory collides with the user's + requested fd, then the user's fd must have been closed to + begin with. */ + free_cwd (&saved_cwd); + errno = EBADF; + return -1; + } if (fchdir (fd) != 0) {
--- a/lib/openat.c +++ b/lib/openat.c @@ -202,6 +202,15 @@ openat_save_fail (errno); *cwd_errno = errno; } + if (0 <= fd && fd == saved_cwd.desc) + { + /* If saving the working directory collides with the user's + requested fd, then the user's fd must have been closed to + begin with. */ + free_cwd (&saved_cwd); + errno = EBADF; + return -1; + } err = fchdir (fd); saved_errno = errno;