Re: [PATCH v4 2/3] git-compat-util: avoid failing dir ownership checks if running privileged

Carlo Arenas [off-list ref] writes:

quoted

Does Windows provide sudo that leaves the original user in SUDO_UID
(I doubt it)?  If not, then "on a platform that provides sudo, it will"
would be sufficient.

At least my windows box does not, but dscho's somehow had and so that
line was added at his request[1] after he wasted so much time trying
to get this to work and realized the function where SUDO_UID logic
resides doesn't even exist in a Windows build.

Ahh, of course.  

I forgot that this patch sent into is_path_owned_by_current_uid(),
as a UID as a value of some integer type is not a thing on Windows.
OK, so it does need to be as you wrote to mean "not on Windows, and
with 'sudo' that uses 'SUDO_UID' to record from whom 'root' came".

OK.

quoted

quoted

+ * In the unlikely scenario this happened to you, and that is how you
+ * got to this message, we would like to know about it by letting us
+ * now with an email to git@vger.kernel.org indicating which platform,
+ * you are running on and which version of sudo you used to see if we
+ * can provide you a patch that would prevent this issue in the future.

Nice.  What message does the reporter see?

when using `sudo git status` a rejection of access to the directory they own

It may have been obvious to who wrote the above comment, but it was
not, at least to me.

quoted

quoted

+ */
+static inline void extract_id_from_env(const char *env, uid_t *id)
+{
+     const char *real_uid = getenv(env);
+
+     /* discard anything empty to avoid a more complex check below */
+     if (real_uid && *real_uid) {
+             char *endptr = NULL;
+             unsigned long env_id;
+
+             errno = 0;
+             /* silent overflow errors could trigger a bug below */

What "bug" are we referring to?

All of them, the ones we decided to ignore because they are irrelevant
when running as root, and the ones that are documented in the long
paragraph above.

Likewise.  It did not click "a bug below" referred to "your sudo is
behaving in a way different from what we expected".

Thanks.