Re: [PATCH v5 2/2] merge-ort: return early when failing to write a blob

From: Junio C Hamano <gitster@pobox.com>
Date: Sep 28, 2022, 15:53 UTC
Message-ID: <xmqqleq3zea3.fsf@gitster.g>
In-Reply-To: <bfc71a2d8adfbf9b899a47d469fe2343e4703ff7.1664350162.git.gitgitgadget@gmail.com>

"Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com> writes:

Show 21 quoted lines

> This is _not_ just a cosmetic change: Even though one might assume that
> the operation would have failed anyway at the point when the new tree
> object is written (and the corresponding tree object _will_ be new if it
> contains a blob that is new), but that is not so: As pointed out by
> Elijah Newren, when Git has previously been allowed to add loose objects
> via `sudo` calls, it is very possible that the blob object cannot be
> written (because the corresponding `.git/objects/??/` directory may be
> owned by `root`) but the tree object can be written (because the
> corresponding objects directory is owned by the current user). This
> would result in a corrupt repository because it is missing the blob
> object, and with this here patch we prevent that.
>
> Note: This patch adjusts two variable declarations from `unsigned` to
> `int` because their purpose is to hold the return value of
> `handle_content_merge()`, which is of type `int`. The existing users of
> those variables are only interested whether that variable is zero or
> non-zero, therefore this type change does not affect the existing code.
>
> Reviewed-by: Elijah Newren <newren@gmail.com>
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---

Thanks. The first paragraph in the quoted part above is new and not exactly "reviewed" by Elijah yet, so let's ask ;-)

To me the description of the issue looks reasonable to me. Any comments, Elijah?

The code is the same as the one in the previous round and Elijah gave his Reviewed-by, and does look good to me, too.

>  merge-ort.c | 28 +++++++++++++++++++---------
>  1 file changed, 19 insertions(+), 9 deletions(-)

Thanks, all.  Queued.