From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FCE145D180; Sat, 26 Sep 2026 13:17:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790428647; cv=none; b=dtmulvtGtImSx/TSpqxTX8NLvAIDg7Hg13kuwq6808MjxtMoyCcswhuLwzpD5tSqHJ/QPHqemidlg6siJ3Yx3kYySXcyKV0FPQZPyAa+ZBCgQTn0kMzU8jVEAzx795nerW2fyyLwUOe9wOtxUda7WCmSRZDz6OOcB//JD+yA4+A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790428647; c=relaxed/simple; bh=qlKpIS0kYvsCmMZPm9g3cnnWgN6jr43hgjF/R4k10xk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=nKB1psRzHJ0IFzQbSnNoPH1b0d5zXblH4j/IDZWsMy0YDBqzbXt1pmjK3SVf9/u5LKpvz6r0e3OCwMG/rkGM5d1Liz7UvCoTDwAKdDcVoIE68UhfM87qdCRClT+WaAKYvLggCjqEvweufA0BU6SMIyRCQciZzCnE1Fywk69Fwxw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c6hsqenm; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c6hsqenm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7238C1F00893; Sat, 26 Sep 2026 13:17:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790428646; bh=iQnzgzJlbml6qFFICw9e5A4EzueJyltcPpFfUYnosW4=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=c6hsqenm0bpKhgnA6m71tv9/GuHSXGFCPIYdm1NxTsO0virkycHxbC7eDP1D34hVf do0edCXBoYtAhUmIvfUybAyIzZbexIU50Olza3am/sUzRhFNqRCtbDVjRYbBqqMoQ1 E46aopb+kQT36s3I8kK86LR6klCrpl1GB/+SiKQI9U/uPbxF1zykj2l8r6ZxT2chEs nagz2ryolNAq94oBGA6mSUC5opx3y3FPE1ObztndNFrW8CS44gwUPNxdYSqIDZ57UA 9ygXeUGobSNnw+wmWlGF/2ZFRRD+OPp4EF9XfnYaFQ60Jr1ndY21OnyInxg0PEqQEX wDEUwoD/N4MhA== From: "Lorenzo Stoakes (ARM)" Date: Sat, 26 Sep 2026 14:17:01 +0100 Subject: [PATCH 3/6] HID: picoLCD: check for fb_deferred_io_init() error Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260926-fix-fbdefio-error-handling-v1-3-a94810b6e263@kernel.org> References: <20260926-fix-fbdefio-error-handling-v1-0-a94810b6e263@kernel.org> In-Reply-To: <20260926-fix-fbdefio-error-handling-v1-0-a94810b6e263@kernel.org> To: Helge Deller , Javier Martinez Canillas , Thomas Zimmermann , =?utf-8?q?Bruno_Pr=C3=A9mont?= , Jiri Kosina , Benjamin Tissoires , Bernie Thompson , Greg Kroah-Hartman , Steve Glendinning , Florian Tobias Schandinat Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, Steve Glendinning , "Lorenzo Stoakes (ARM)" , stable@vger.kernel.org X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1697; i=ljs@kernel.org; h=from:subject:message-id; bh=qlKpIS0kYvsCmMZPm9g3cnnWgN6jr43hgjF/R4k10xk=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLK2H70y1Us18tk+S00BxiLnqa6cz9TsTv9rfqMT4bzP2 Lc3OelIRykLgxgXg6yYIsvzL+L7g0TC5nVe8HeDmcPKBDKEgYtTACaSc5GR4d/Ozur/J0NSN8aX Pzxks1305T2da3v7HPZUfLRR3PCm6Akjw19vRbl/5+3v3hJifWl04uT8H9nF82dZL9q7snB6MOM 3DXYA X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 fb_deferred_io_init() allocates deferred I/O state, populating info->fbdefio_state, or leaving it NULL if an error occurs. Currently picolcd_init_framebuffer() ignores its return value. Therefore if an error arises in fb_deferred_io_init() (for instance, due to an allocation failure) info->fbdefio_state is left NULL. When the file is subsequently opened, fb_open() will dereference a NULL pointer (calling fb_deferred_io_open()). Fix this by checking for the error. Also correct cleanup ordering - defio is initialised after the sysfs file, so cleanup defio first. Fixes: 56c134f7f1b5 ("fbdev: Track deferred-I/O pages in pageref struct") Cc: Signed-off-by: Lorenzo Stoakes (ARM) --- drivers/hid/hid-picolcd_fb.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/hid/hid-picolcd_fb.c b/drivers/hid/hid-picolcd_fb.c index 8c28e982e09d..a016dd9ca847 100644 --- a/drivers/hid/hid-picolcd_fb.c +++ b/drivers/hid/hid-picolcd_fb.c @@ -531,17 +531,23 @@ int picolcd_init_framebuffer(struct picolcd_data *data) goto err_cleanup; } - fb_deferred_io_init(info); + error = fb_deferred_io_init(info); + if (error) { + dev_err(dev, "failed to initialize deferred I/O\n"); + goto err_sysfs; + } + error = register_framebuffer(info); if (error) { dev_err(dev, "failed to register framebuffer\n"); - goto err_sysfs; + goto err_defio; } return 0; +err_defio: + fb_deferred_io_cleanup(info); err_sysfs: device_remove_file(dev, &dev_attr_fb_update_rate); - fb_deferred_io_cleanup(info); err_cleanup: data->fb_info = NULL; -- 2.55.0