From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.3 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 32726 invoked from network); 8 Oct 2021 12:13:47 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 8 Oct 2021 12:13:47 -0000 Received: (qmail 19698 invoked by uid 550); 8 Oct 2021 12:13:45 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 19680 invoked from network); 8 Oct 2021 12:13:44 -0000 X-Gm-Message-State: AOAM533BBGxeJOJ/QyPJPjCJwCr+4JlvJfTpf7YKlbq2I0xZMwnobd/A 3I8+/10k4N+/4DM2OM1h4xNp93f82oaNVCfRHfQ= X-Google-Smtp-Source: ABdhPJx1A2D3uT0vzkwBBgcqCmigtym207jBkyjcfjbAUCVSC7jvNZMRoRn37wH1p1cCJbv0expgQMHr7/L53iVVxso= X-Received: by 2002:adf:a3da:: with SMTP id m26mr3519436wrb.336.1633695212568; Fri, 08 Oct 2021 05:13:32 -0700 (PDT) MIME-Version: 1.0 References: <20191211212025.1981822-1-arnd@arndb.de> <20191211212025.1981822-9-arnd@arndb.de> <29QBMJU8DE71E.2YZSH8IHT5HMH@mforney.org> <20211007160634.GB7074@brightrain.aerifal.cx> <20211007165158.GC7074@brightrain.aerifal.cx> In-Reply-To: From: Arnd Bergmann Date: Fri, 8 Oct 2021 14:13:16 +0200 X-Gmail-Original-Message-ID: Message-ID: To: musl@lists.openwall.com Cc: Arnd Bergmann , Rich Felker , Michael Forney , ALSA Development Mailing List , Takashi Iwai , Baolin Wang , y2038 Mailman List , Linux Kernel Mailing List , Mark Brown , Baolin Wang Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:9bM3dCs3tgw0CeZCrO5QScIPwshLMGVBCvDXLEL4r49fplJEjH3 2lXguCYpNARz2fx8iU1RU/RhJRpAQ2pnubmONbyveW/Ea4ZwHk4ZRk0JNfU7581u1EWFOBh zZX6VGJW0C3Z3N9pwBUyBCxY4bjuqRLdEOezJ6IcmIo3/Pr+PjhG2su2N7xULySH4pV+Pha A9z5ebIrbGYJmithg8SIg== X-UI-Out-Filterresults: notjunk:1;V03:K0:sz3+aZBJ840=:hJp8GOGbDPacSiK8ZNPt4Z qDBm4RwXgIrALmBGSfRXJgaVc+b8dC53XbLwYjqqsxlWnz3cbJBuvAvsHIAnUE/LpNo2eFblC GSo9kLEuTMidwuLd9H5XXj6HwNz/gKaNn0LJc11zMYL/VkQFlM9rRm3hcOJKp/wJeho8YDNIZ PQX0HBc45pqEoX/YGVuEogY/axwotq+qFzrIaDvKk4suvp9/5bKyIgKjsXYUUFpiNpdPWUnmF LMtyM8f0K67ARroGlUL9PuQIuOQGU5lp6pJYBxSpY5vn1xkJ9WCIaIdMPRe7b03pJ0CA1uruI zCMhlNdLGrbt/Q8Y2OSHns9jS4q3/ECZhJ6LDNX0B3aTLXsD4ErdbbTlEoM/MaJM1P22htt8f xOFH2QbRvuRCorrNLnb7eug4/frlMOOuS6PM2Z3y7E2HCfBbBVzloLdxzm7hxx1FWOuKhl2Ov Owx8lxksXqmLCDwSWj9IYcl/WX5AG2dDF5wah+1GD53HzKe7BSYZj0HzP1kxGCChoR9Qwcn38 e+gDkns51/fGCEXvDxUOuOPt8vz/b+p31xCGCWd70MAvz+F/66Ne2MH/lTzkywuUpkX/DLcMq bs0p05jsE2HNJsbP8w4OR9NEdkoDNv3z9Z1Rf+QN2+auq1D+eOJnKzrmiUT8YBM2yxAwx3unD H8yKGcX85HxM2gdrbaNC/hrqjPQdvQjxoUmTbJsA5vF15RQcHwHDfIxaajXJRQwKLQHeKDBWZ bpH0NmXALfEgLtGmhsJVXVrlGEPbnrQIAt2EVqjW4wGUYFGwxpKq7jUIKIafye5m61U7XqBJ+ xY9CqukRQphmXB/pIgyb7E4V8qZo5yflxzRixjME+s39kuex6K3jliiX092QMs4ZZHmuYMYhh JsPR1SJhosjlETh7toxQ== Subject: Re: [musl] Re: [alsa-devel] [PATCH v7 8/9] ALSA: add new 32-bit layout for snd_pcm_mmap_status/control On Fri, Oct 8, 2021 at 1:53 PM Takashi Iwai wrote: > On Fri, 08 Oct 2021 13:45:45 +0200, Arnd Bergmann wrote: > > On Fri, Oct 8, 2021 at 1:11 PM Takashi Iwai wrote: > > > On Fri, 08 Oct 2021 11:24:39 +0200, Arnd Bergmann wrote: > > > The below is a revised kernel patch (again untested), just correcting > > > the behavior of 32bit compat mode. 32bit apps on 32bit kernel work > > > fine as is, as well as 64bit apps on 64bit kernel. > > > > Right, this should cover all cases of the ioctl itself misbehaving. > > In addition, we still need to disallow the mmap() interface on compat > > kernels then. Strictly speaking, we could allow the snd_pcm_mmap_status > > but not snd_pcm_mmap_control to be mapped, but I'm not sure if > > that's better than disallowing both. > > IIRC, the compat mmap is already disallowed even for the > SNDRV_PCM_MMAP_OFFSET_CONTROL_NEW (in pcm_control_mmap_allowed()), so > no need to change around that. Ah, right. I think it was meant to become allowed as part of commit 80fe7430c708 ("ALSA: add new 32-bit layout for snd_pcm_mmap_status/control"), which did allow the snd_pcm_mmap_status to be mmap()ed, but it appears to be the rare case where two mistakes cancel out and we don't have to change the mmap code. Arnd