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 1546F448CE0; Sat, 26 Sep 2026 13:17:17 +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=1790428639; cv=none; b=KKe7mZwWxD6CdzvyvrebhNK1vsJoe6eCh7KEwp4Md7ohoSeY0aDBqlJQuCD7iQ5pqRGxpxrRLvVKKM+VlujsCawcOOKGWVa3A9eqXzR/f/ZBeuo7LRGN5UQmMKTZWCkJUJCN6B+Iym09BiLsZKyOCLJs7Y6kMaezbMescUaUv+E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790428639; c=relaxed/simple; bh=TYvmmecMami2PR29JEAo0nLEjXwWhtuhMjvkFJ2CNPs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=NvyuVzDGG2lsSO6/ZR8gu6FlB8x1SjppFCv+JcfpqkPwnCg4473F7kwxLN+rbFWa0benmQr2QGrghPGz0QH/0vgQ3MEv1wZWC4Gux2qujubE4LXIiH1ZsZ5qJKS1RURXicZFaZXnzJuw9WiUZqJRQ2AZsPC0Ek3q0MTGSAl2oD8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BRa7wKuX; 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="BRa7wKuX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8DEB1F00898; Sat, 26 Sep 2026 13:17:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790428637; bh=53Vc8WVIQr3ly0MiN9XWVCDubq5i8iA9A9qjfXDRuWE=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=BRa7wKuX3bw2/eV1pOhXQ0qTNNdNXrUr8DdtjjxQ66H/QfIC0yz1VGW4eCKVDRLlt uo2GurglwXgKbQnZLriw7O6qfybCepFV/PMXsZey5hlLrRNbD1azFN6YMPSXg/74mq bDj2iY19taqI/sC9xsJ875dnxcEUoVKZyHDtzN8TMGKIQNr1OeX8611q/MQ9Thqy/r lslHcxys8r1zRIBBin9kqDLDkRUXnbtJjqtCH3QJ4Rs9KsjGVGNQMDHMk/gC99ZWnY JQiAx67oXpXM+rfEMpZJKId/K9tNTpIm3TWOhZdLdUKZavO9GyaI94sT61HcK/6Swj vQIpmtQyHzsGg== From: "Lorenzo Stoakes (ARM)" Date: Sat, 26 Sep 2026 14:16:59 +0100 Subject: [PATCH 1/6] fbdev: ssd1307fb: 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-v1-1-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=1319; i=ljs@kernel.org; h=from:subject:message-id; bh=TYvmmecMami2PR29JEAo0nLEjXwWhtuhMjvkFJ2CNPs=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLK2H70y5dyre+Xf3xw59OP3c6/kvF/SF1ZJbGb/Ub5iW 9rc9PUNrztKWRjEuBhkxRRZnn8R3x8kEjav84K/G8wcViaQIQxcnAIwEcMCRoY17e2v6zT/MBz5 vvnCv9Iwllnul3Z/SXjtohF67o8Z0yIrhv/Vuz9Ghgp+4Lvy+YS1bSGHPmvfqknCZ19vr12mM7M yOZIDAA== 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 ssd1307fb_probe() 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. Fixes: 56c134f7f1b5 ("fbdev: Track deferred-I/O pages in pageref struct") Cc: Signed-off-by: Lorenzo Stoakes (ARM) --- drivers/video/fbdev/ssd1307fb.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c index 4d185c754284..8fd96c37ee1a 100644 --- a/drivers/video/fbdev/ssd1307fb.c +++ b/drivers/video/fbdev/ssd1307fb.c @@ -767,7 +767,11 @@ static int ssd1307fb_probe(struct i2c_client *client) info->fix.smem_start = __pa(vmem); info->fix.smem_len = vmem_size; - fb_deferred_io_init(info); + ret = fb_deferred_io_init(info); + if (ret) { + dev_err(dev, "failed to init fb deferred io: %d\n", ret); + goto fb_defio_error; + } i2c_set_clientdata(client, info); -- 2.55.0