From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1F1007E772; Mon, 8 Apr 2024 13:27:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712582875; cv=none; b=jgBqRz9m1+mbqIBCwK5TiC5pMT9Nppp6JVFy8Iu96VwOlc+oHMA1hFYHU0PHtNtAERACEUjT3NJMlXgVcqiHY+BAK/6aR4nEkwdRa8rgcs9Q6APl6j7w/cu1K2y7JFud8qjIrEsrnhZCLP3QhXRn+JB2zUACLLjw/H+McbsJk7I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712582875; c=relaxed/simple; bh=PmTEF4Kju6V9vPMopSs1KQrQVZZGahxKZmFKYnT8UL8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Sf/q1/0/DJPl9ttntiYbkcC8THslmNS+UuOGyvwDz/TL86S2av1OivmUz1QbRLdbgGkEZUMZi3UmdaaDhqNTKqwbj2ZCIFOn/d+nyLJLe2hibLrt2Gy3L36y7JwYBs1zGT/+L+FhbZSA15FmhYvqLbnSlqPHc9TqEhzIGvDOYQ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AaHcATD7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="AaHcATD7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58DB5C433C7; Mon, 8 Apr 2024 13:27:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712582874; bh=PmTEF4Kju6V9vPMopSs1KQrQVZZGahxKZmFKYnT8UL8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AaHcATD7Wkn+gDCbTaVMiaytjczL/Wy806G/UDKmS3WJLC5F5lECwYo4gYBm08nMv P8J2rT1wpkH0DvmRFnK9Ci3QxNvlrDzgib9VB3hyHn1GUR8/KohNgHlwt1cvNWA49h IJAm5k4IMMfxJbwKEYRVvgCcHR9Kh8m+hZmu2bz8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexander Wetzel , Bart Van Assche , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 6.6 131/252] scsi: sg: Avoid sg device teardown race Date: Mon, 8 Apr 2024 14:57:10 +0200 Message-ID: <20240408125310.696651813@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125306.643546457@linuxfoundation.org> References: <20240408125306.643546457@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Wetzel [ Upstream commit 27f58c04a8f438078583041468ec60597841284d ] sg_remove_sfp_usercontext() must not use sg_device_destroy() after calling scsi_device_put(). sg_device_destroy() is accessing the parent scsi_device request_queue which will already be set to NULL when the preceding call to scsi_device_put() removed the last reference to the parent scsi_device. The resulting NULL pointer exception will then crash the kernel. Link: https://lore.kernel.org/r/20240305150509.23896-1-Alexander@wetzel-home.de Fixes: db59133e9279 ("scsi: sg: fix blktrace debugfs entries leakage") Cc: stable@vger.kernel.org Signed-off-by: Alexander Wetzel Link: https://lore.kernel.org/r/20240320213032.18221-1-Alexander@wetzel-home.de Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/sg.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 0d8afffd1683b..8bd95ee1825a6 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -2208,6 +2208,7 @@ sg_remove_sfp_usercontext(struct work_struct *work) { struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work); struct sg_device *sdp = sfp->parentdp; + struct scsi_device *device = sdp->device; Sg_request *srp; unsigned long iflags; @@ -2233,8 +2234,9 @@ sg_remove_sfp_usercontext(struct work_struct *work) "sg_remove_sfp: sfp=0x%p\n", sfp)); kfree(sfp); - scsi_device_put(sdp->device); + WARN_ON_ONCE(kref_read(&sdp->d_ref) != 1); kref_put(&sdp->d_ref, sg_device_destroy); + scsi_device_put(device); module_put(THIS_MODULE); } -- 2.43.0