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[177.4.161.87]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-12c8e837beasm24410043c88.11.2026.04.24.05.14.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 24 Apr 2026 05:14:05 -0700 (PDT) Message-ID: <87797cae-2716-48e2-b0ba-47cdfb34645f@gmail.com> Date: Fri, 24 Apr 2026 09:14:00 -0300 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] ALSA: aloop: Fix peer runtime UAF during format-change stop To: Takashi Iwai Cc: Takashi Iwai , Jaroslav Kysela , linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+8fa95c41eafbc9d2ff6f@syzkaller.appspotmail.com, stable@vger.kernel.org References: <20260423-alsa-aloop-peer-stop-uaf-v1-1-25d8a9745f6c@gmail.com> <87se8k1ugc.wl-tiwai@suse.de> From: =?UTF-8?Q?C=C3=A1ssio_Gabriel_Monteiro_Pires?= Content-Language: en-US In-Reply-To: <87se8k1ugc.wl-tiwai@suse.de> Content-Type: multipart/signed; micalg=pgp-sha256; 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charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 4/24/26 08:14, Takashi Iwai wrote:=20 > Do we need to complicate this handling? IOW, can it be simply be like > below? >=20 > if (stop_capture) { > snd_pcm_stop(dpcm_capt->substream, SNDRV_PCM_STATE_DRAINING); > if (atomic_dec_and_test(&cable->stop_count)) > wake_up(&cable->stop_wait); > } That makes sense. The lifetime fix only needs the stop_count/stop_wait serialization, so I can simplify the stop path as you suggested. I'll respin and send a v2 patch.=20 --=20 Thanks, C=C3=A1ssio --------------10n2GPumHEzMlOIESxT5WexW-- --------------bzN3VwiHVvH0SN3pB5H2yyYv Content-Type: application/pgp-signature; name="OpenPGP_signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- wnsEABYIACMWIQSrYqI5vIrg1X9eqEjQXT8aWv/ugwUCaeteiAUDAAAAAAAKCRDQXT8aWv/ug2iT AP0X/ZNOWh5f2N2Fmo23q2Y88xT52Ml+kNwydxlmScVMoAEA/W23y48fC9MVXJEcBMn/i3U5Lkc1 4wiaC5RJSFk+0AM= =+C0T -----END PGP SIGNATURE----- --------------bzN3VwiHVvH0SN3pB5H2yyYv--