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To:     gregkh@linuxfoundation.org
Cc:     axboe@kernel.dk, linux-kernel@vger.kernel.org, wang6495@umn.edu
References: <20210421130105.1226686-168-gregkh@linuxfoundation.org>
Subject: Re: [PATCH 167/190] Revert "gdrom: fix a memory leak bug"
From:   Peter Rosin <peda@axentia.se>
Organization: Axentia Technologies AB
Message-ID: <23ffd3c5-0095-6a95-8c30-2b6f67377ce7@axentia.se>
Date:   Thu, 22 Apr 2021 23:29:22 +0200
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> This reverts commit 093c48213ee37c3c3ff1cf5ac1aa2a9d8bc66017.

The reverted patch looks fishy.

gc.cd_info is kzalloc:ed on probe. In case probe fails after this allocation, the
memory is kfree:d but the variable is NOT zeroed out.

AFAICT, the above leads to a double-free on exit by the added line.

I believe gd.cd_info should be kfree:d on remove instead.

However, might not gc.toc also be kfree:d twice for similar reasons?

I could easily be mistaken.

Cheers,
Peter