[hurd,commited,1/5] hurd: Fix O_NOFOLLOW
Commit Message
The error code documented by POSIX for opening a symlink with O_NOFOLLOW
is ELOOP.
Also, if the translator does not expose symlink as a symlink translator but
as a S_IFLNK file, O_NOFOLLOW needs to return ELOOP too.
* hurd/lookup-retry.c (__hurd_file_name_lookup_retry): Return ELOOP
when opening a symlink with O_NOFOLLOW.
---
ChangeLog | 2 ++
hurd/lookup-retry.c | 36 ++++++++++++++++++++----------------
2 files changed, 22 insertions(+), 16 deletions(-)
@@ -62,6 +62,8 @@
2018-03-18 Samuel Thibault <samuel.thibault@ens-lyon.org>
* sysdeps/mach/hurd/cthreads.c: Include <cthreads.h>.
+ * hurd/lookup-retry.c (__hurd_file_name_lookup_retry): Return ELOOP
+ when opening a symlink with O_NOFOLLOW.
2018-03-17 Samuel Thibault <samuel.thibault@ens-lyon.org>
@@ -127,7 +127,7 @@ __hurd_file_name_lookup_retry (error_t (*use_init_port)
{
/* In Linux, O_NOFOLLOW means to reject symlinks. If we
did an O_NOLINK lookup above and io_stat here to check
- for S_IFLNK, a translator like firmlink could easily
+ for S_IFLNK only, a translator like firmlink could easily
spoof this check by not showing S_IFLNK, but in fact
redirecting the lookup to some other name
(i.e. opening the very same holes a symlink would).
@@ -145,23 +145,27 @@ __hurd_file_name_lookup_retry (error_t (*use_init_port)
one exception to our general translator-based rule. */
struct stat64 st;
err = __io_stat (*result, &st);
- if (!err
- && (st.st_mode & (S_IPTRANS|S_IATRANS)))
+ if (!err)
{
- if (st.st_uid != 0)
- err = ENOENT;
- else if (st.st_mode & S_IPTRANS)
+ if (S_ISLNK (st.st_mode))
+ err = ELOOP;
+ else if (st.st_mode & (S_IPTRANS|S_IATRANS))
{
- char buf[1024];
- char *trans = buf;
- size_t translen = sizeof buf;
- err = __file_get_translator (*result,
- &trans, &translen);
- if (!err
- && translen > sizeof _HURD_SYMLINK
- && !memcmp (trans,
- _HURD_SYMLINK, sizeof _HURD_SYMLINK))
- err = ENOENT;
+ if (st.st_uid != 0)
+ err = ELOOP;
+ else if (st.st_mode & S_IPTRANS)
+ {
+ char buf[1024];
+ char *trans = buf;
+ size_t translen = sizeof buf;
+ err = __file_get_translator (*result,
+ &trans, &translen);
+ if (!err
+ && translen > sizeof _HURD_SYMLINK
+ && !memcmp (trans,
+ _HURD_SYMLINK, sizeof _HURD_SYMLINK))
+ err = ELOOP;
+ }
}
}
}