From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1E1AE26E6F3 for ; Mon, 25 May 2026 07:23:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779693808; cv=none; b=fWqG1BsMFpKYhMJZeKlxJeBe9C61W45wzSU2ZNlqpgjhHsWpg3ajK2nYFesVyEtAetb4lTUv8boiTc/m2DSB727BqT750mKssMtuA565WuRDrKUIDxvgnTn9IMImBEcn171aXSUAlaDla5m7FvGmsUHg+yMdfcY4y94lZN62btU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779693808; c=relaxed/simple; bh=16AzfyjkFGYPQLSiMvzRihkksc8m1m/DNzRYBjGi/Rc=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=XiPNew1zsRjd77X9m5HmjoPk0zWTb+Kha4OHPrmImGW58cVI/VbKsMBuLa4Clpe3Ogy6Ka+EuGuag27KXqcJyfwMXggHpexNubFi1199hGVkDfzd6uXF6naleVjFKLcY4GVVZAHoME+vP5v6tylnPbDXyxN99TJXUPDl709GBa4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de; spf=pass smtp.mailfrom=suse.de; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=h6MVOI0T; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=SsJqtrv8; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=h6MVOI0T; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=SsJqtrv8; arc=none smtp.client-ip=195.135.223.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="h6MVOI0T"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="SsJqtrv8"; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="h6MVOI0T"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="SsJqtrv8" Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 5D01F68A24; Mon, 25 May 2026 07:23:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1779693805; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OwKAHCPufmcvwmVoubxbEP61XxbKOS+31Zsa7Rt93Ks=; b=h6MVOI0TM6zdX0c7JNRu1a78H/NNU/CgH6z7NLaV/BxgGler1E5aIdEjKAPcMpGXC7qFLM mQdqgpjrCkdfj9l+BF/Fgfkr2d7LWgqUabVFPcqU6ksd59J2va1BrKrWa8ScGVe0l/DKE5 KfIIA7X4w3zQy4b3OnPKQRN76lXgKPk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1779693805; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OwKAHCPufmcvwmVoubxbEP61XxbKOS+31Zsa7Rt93Ks=; b=SsJqtrv8yzohfaISo7DeLBXGiD8n/HaQl0SgqWu+DKWLTweJf3O9cSu36dWSalQkUkd2fJ 28zIktwc965LVnAg== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1779693805; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OwKAHCPufmcvwmVoubxbEP61XxbKOS+31Zsa7Rt93Ks=; b=h6MVOI0TM6zdX0c7JNRu1a78H/NNU/CgH6z7NLaV/BxgGler1E5aIdEjKAPcMpGXC7qFLM mQdqgpjrCkdfj9l+BF/Fgfkr2d7LWgqUabVFPcqU6ksd59J2va1BrKrWa8ScGVe0l/DKE5 KfIIA7X4w3zQy4b3OnPKQRN76lXgKPk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1779693805; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=OwKAHCPufmcvwmVoubxbEP61XxbKOS+31Zsa7Rt93Ks=; b=SsJqtrv8yzohfaISo7DeLBXGiD8n/HaQl0SgqWu+DKWLTweJf3O9cSu36dWSalQkUkd2fJ 28zIktwc965LVnAg== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 2C57159B07; Mon, 25 May 2026 07:23:25 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 5BZXCe34E2rxEgAAD6G6ig (envelope-from ); Mon, 25 May 2026 07:23:25 +0000 Date: Mon, 25 May 2026 09:23:24 +0200 Message-ID: <87cxykgdg3.wl-tiwai@suse.de> From: Takashi Iwai To: =?ISO-8859-1?Q?C=E1ssio?= Gabriel Cc: Takashi Iwai , Jaroslav Kysela , linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+8e498074a794999eb41c@syzkaller.appspotmail.com Subject: Re: [PATCH] ALSA: pcm: oss: Fix setup list UAF on proc write error In-Reply-To: <20260522-alsa-pcm-oss-setup-uaf-v1-1-40bdcc4d17e8@gmail.com> References: <20260522-alsa-pcm-oss-setup-uaf-v1-1-40bdcc4d17e8@gmail.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/30.2 Mule/6.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Spam-Score: -1.80 X-Spamd-Result: default: False [-1.80 / 50.00]; BAYES_HAM(-3.00)[99.99%]; SUSPICIOUS_RECIPS(1.50)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MID_CONTAINS_FROM(1.00)[]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_TO(0.00)[gmail.com]; FUZZY_RATELIMITED(0.00)[rspamd.com]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RCVD_TLS_ALL(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[6]; RCVD_COUNT_TWO(0.00)[2]; RCVD_VIA_SMTP_AUTH(0.00)[]; TAGGED_RCPT(0.00)[8e498074a794999eb41c]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:mid,imap1.dmz-prg2.suse.org:helo] X-Spam-Level: X-Spam-Flag: NO On Sat, 23 May 2026 03:09:40 +0200, Cássio Gabriel wrote: > > snd_pcm_oss_proc_write() links a newly allocated setup entry into the > OSS setup list before duplicating the task name. If the task-name > allocation fails, the error path frees the already linked entry and > leaves setup_list pointing at freed memory. > > A later OSS device open can then walk the stale list entry in > snd_pcm_oss_look_for_setup() and dereference freed memory. > > Allocate the task name and initialize the setup entry before publishing > the entry on setup_list. Also fetch the initial proc read iterator only > after taking setup_mutex, so all setup_list traversal follows the same > list lifetime rules. > > Reported-by: syzbot+8e498074a794999eb41c@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/all/6a1062b7.170a0220.35b2b7.0003.GAE@google.com > Closes: https://syzkaller.appspot.com/bug?extid=8e498074a794999eb41c > Fixes: 060d77b9c04a ("[ALSA] Fix / clean up PCM-OSS setup hooks") > Signed-off-by: Cássio Gabriel Applied now. Thanks. Takashi