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From:   Benjamin Tissoires <benjamin.tissoires@redhat.com>
To:     Jiri Kosina <jikos@kernel.org>,
        =?UTF-8?q?Andr=C3=A9=20Almeida?= <andrealmeid@igalia.com>,
        Ludvig Michaelsson <ludvig.michaelsson@yubico.com>
Cc:     Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] HID: hidraw: fix data race on device refcount
Date:   Wed, 21 Jun 2023 17:55:14 +0200
Message-Id: <168736288418.3423010.16497710719241305762.b4-ty@redhat.com>
In-Reply-To: <20230621-hidraw-race-v1-1-a58e6ac69bab@yubico.com>
References: <20230621-hidraw-race-v1-1-a58e6ac69bab@yubico.com>
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On Wed, 21 Jun 2023 13:17:43 +0200, Ludvig Michaelsson wrote:
> The hidraw_open() function increments the hidraw device reference
> counter. The counter has no dedicated synchronization mechanism,
> resulting in a potential data race when concurrently opening a device.
> 
> The race is a regression introduced by commit 8590222e4b02 ("HID:
> hidraw: Replace hidraw device table mutex with a rwsem"). While
> minors_rwsem is intended to protect the hidraw_table itself, by instead
> acquiring the lock for writing, the reference counter is also protected.
> This is symmetrical to hidraw_release().
> 
> [...]

Added stable@ cc tags and

Applied to hid/hid.git (for-6.4/upstream-fixes), thanks!

[1/1] HID: hidraw: fix data race on device refcount
      https://git.kernel.org/hid/hid/c/944ee77dc6ec

Cheers,
-- 
Benjamin Tissoires <benjamin.tissoires@redhat.com>