From patchwork Sat Oct 19 16:07:57 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ricardo Ribalda Delgado X-Patchwork-Id: 3072221 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 966FE9F2B6 for ; Sat, 19 Oct 2013 16:08:55 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 889E820511 for ; Sat, 19 Oct 2013 16:08:54 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5C889203F7 for ; Sat, 19 Oct 2013 16:08:53 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VXZ54-000563-FR; Sat, 19 Oct 2013 16:08:46 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VXZ51-0005Yw-Um; Sat, 19 Oct 2013 16:08:43 +0000 Received: from mail-la0-x229.google.com ([2a00:1450:4010:c03::229]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VXZ4z-0005YE-B5 for linux-arm-kernel@lists.infradead.org; Sat, 19 Oct 2013 16:08:42 +0000 Received: by mail-la0-f41.google.com with SMTP id el20so1508806lab.0 for ; Sat, 19 Oct 2013 09:08:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=btvLDd9nXTMyKA4a2JhPCwPzI4WwVwQVPAuhZxMQo80=; b=zp/VeLeTJcJ87VKATezUah3OGQjiB4kvCwkr6kOMALtaGLDs/tWF0GE9erenZdL/tH qvhnxMZvQV7w0/B3WPRjYIEKJ348FjQTXNYYMEiQCdjM43q+wuSzQ8h9ENz5n7uTa2NF 6x7Ydoz1hUN0262u4hoi19MsEf20Y6UCP12UfTkMTzWm2qKJ816g4KESiCx5VZKn7fUy rTR9H3GBRaRbIz5/ZTaAhOSnLXIO6umsZXZ1/huwMOTO5OIjURXgMraCjEeA7Snz/nOe f6wwtczsUiTfM/qNs9kPoUcGwU0AO9c0gHHxch52g4gYluIafV08hPHSjfMm20nPw+CJ A/Qg== X-Received: by 10.112.64.36 with SMTP id l4mr6467168lbs.15.1382198898830; Sat, 19 Oct 2013 09:08:18 -0700 (PDT) Received: from localhost.localdomain (x1-6-30-46-9a-6d-3c-54.k353.webspeed.dk. [80.167.66.223]) by mx.google.com with ESMTPSA id ac2sm5739456lbc.10.2013.10.19.09.08.17 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sat, 19 Oct 2013 09:08:18 -0700 (PDT) From: Ricardo Ribalda To: Kyungmin Park , Sylwester Nawrocki , Mauro Carvalho Chehab , Kukjin Kim , Pawel Osciak , Marek Szyprowski , linux-media@vger.kernel.org (open list:SAMSUNG S5P/EXYNO...), linux-arm-kernel@lists.infradead.org (moderated list:ARM/S5P EXYNOS AR...), linux-samsung-soc@vger.kernel.org (moderated list:ARM/S5P EXYNOS AR...), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2] videobuf2: Add missing lock held on vb2_fop_relase Date: Sat, 19 Oct 2013 18:07:57 +0200 Message-Id: <1382198877-27164-1-git-send-email-ricardo.ribalda@gmail.com> X-Mailer: git-send-email 1.8.3.2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131019_120841_695240_E7093D80 X-CRM114-Status: GOOD ( 19.64 ) X-Spam-Score: -2.0 (--) Cc: Ricardo Ribalda X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.5 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP vb2_fop_relase does not held the lock although it is modifying the queue->owner field. This could lead to race conditions on the vb2_perform_io function when multiple applications are accessing the video device via read/write API: [ 308.297741] BUG: unable to handle kernel NULL pointer dereference at 0000000000000260 [ 308.297759] IP: [] vb2_perform_fileio+0x372/0x610 [videobuf2_core] [ 308.297794] PGD 159719067 PUD 158119067 PMD 0 [ 308.297812] Oops: 0000 #1 SMP [ 308.297826] Modules linked in: qt5023_video videobuf2_dma_sg qtec_xform videobuf2_vmalloc videobuf2_memops videobuf2_core qtec_white qtec_mem gpio_xilinx qtec_cmosis qtec_pcie fglrx(PO) spi_xilinx spi_bitbang qt5023 [ 308.297888] CPU: 1 PID: 2189 Comm: java Tainted: P O 3.11.0-qtec-standard #1 [ 308.297919] Hardware name: QTechnology QT5022/QT5022, BIOS PM_2.1.0.309 X64 05/23/2013 [ 308.297952] task: ffff8801564e1690 ti: ffff88014dc02000 task.ti: ffff88014dc02000 [ 308.297962] RIP: 0010:[] [] vb2_perform_fileio+0x372/0x610 [videobuf2_core] [ 308.297985] RSP: 0018:ffff88014dc03df8 EFLAGS: 00010202 [ 308.297995] RAX: 0000000000000000 RBX: ffff880158a23000 RCX: dead000000100100 [ 308.298003] RDX: 0000000000000000 RSI: dead000000200200 RDI: 0000000000000000 [ 308.298012] RBP: ffff88014dc03e58 R08: 0000000000000000 R09: 0000000000000001 [ 308.298020] R10: ffffea00051e8380 R11: ffff88014dc03fd8 R12: ffff880158a23070 [ 308.298029] R13: ffff8801549040b8 R14: 0000000000198000 R15: 0000000001887e60 [ 308.298040] FS: 00007f65130d5700(0000) GS:ffff88015ed00000(0000) knlGS:0000000000000000 [ 308.298049] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 308.298057] CR2: 0000000000000260 CR3: 0000000159630000 CR4: 00000000000007e0 [ 308.298064] Stack: [ 308.298071] ffff880156416c00 0000000000198000 0000000000000000 ffff880100000001 [ 308.298087] ffff88014dc03f50 00000000810a79ca 0002000000000001 ffff880154904718 [ 308.298101] ffff880156416c00 0000000000198000 ffff880154904338 ffff88014dc03f50 [ 308.298116] Call Trace: [ 308.298143] [] vb2_read+0x14/0x20 [videobuf2_core] [ 308.298198] [] vb2_fop_read+0xc4/0x120 [videobuf2_core] [ 308.298252] [] v4l2_read+0x7e/0xc0 [ 308.298296] [] vfs_read+0xa9/0x160 [ 308.298312] [] SyS_read+0x52/0xb0 [ 308.298328] [] tracesys+0xd0/0xd5 [ 308.298335] Code: e5 d6 ff ff 83 3d be 24 00 00 04 89 c2 4c 8b 45 b0 44 8b 4d b8 0f 8f 20 02 00 00 85 d2 75 32 83 83 78 03 00 00 01 4b 8b 44 c5 48 <8b> 88 60 02 00 00 85 c9 0f 84 b0 00 00 00 8b 40 58 89 c2 41 89 [ 308.298487] RIP [] vb2_perform_fileio+0x372/0x610 [videobuf2_core] [ 308.298507] RSP [ 308.298514] CR2: 0000000000000260 [ 308.298526] ---[ end trace e8f01717c96d1e41 ]--- v2: Add bug found by Sylvester Nawrocki fimc-capture and fimc-lite where calling vb2_fop_release with the lock held. Therefore a new __vb2_fop_release function has been created to be used by drivers that overload the release function. Signed-off-by: Ricardo Ribalda --- drivers/media/platform/exynos4-is/fimc-capture.c | 2 +- drivers/media/platform/exynos4-is/fimc-lite.c | 2 +- drivers/media/usb/em28xx/em28xx-video.c | 2 +- drivers/media/v4l2-core/videobuf2-core.c | 18 +++++++++++++++++- include/media/videobuf2-core.h | 2 ++ 5 files changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/media/platform/exynos4-is/fimc-capture.c b/drivers/media/platform/exynos4-is/fimc-capture.c index fb27ff7..c38d247c 100644 --- a/drivers/media/platform/exynos4-is/fimc-capture.c +++ b/drivers/media/platform/exynos4-is/fimc-capture.c @@ -549,7 +549,7 @@ static int fimc_capture_release(struct file *file) vc->streaming = false; } - ret = vb2_fop_release(file); + ret = __vb2_fop_release(file, true); if (close) { clear_bit(ST_CAPT_BUSY, &fimc->state); diff --git a/drivers/media/platform/exynos4-is/fimc-lite.c b/drivers/media/platform/exynos4-is/fimc-lite.c index e5798f7..021d804 100644 --- a/drivers/media/platform/exynos4-is/fimc-lite.c +++ b/drivers/media/platform/exynos4-is/fimc-lite.c @@ -546,7 +546,7 @@ static int fimc_lite_release(struct file *file) mutex_unlock(&entity->parent->graph_mutex); } - vb2_fop_release(file); + __vb2_fop_release(file, true); pm_runtime_put(&fimc->pdev->dev); clear_bit(ST_FLITE_SUSPENDED, &fimc->state); diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c index 9d10334..6a5c147 100644 --- a/drivers/media/usb/em28xx/em28xx-video.c +++ b/drivers/media/usb/em28xx/em28xx-video.c @@ -1664,7 +1664,7 @@ static int em28xx_v4l2_close(struct file *filp) em28xx_videodbg("users=%d\n", dev->users); mutex_lock(&dev->lock); - vb2_fop_release(filp); + __vb2_fop_release(filp, false); if (dev->users == 1) { /* the device is already disconnect, diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index 594c75e..ce309a8 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -2619,16 +2619,32 @@ int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma) } EXPORT_SYMBOL_GPL(vb2_fop_mmap); -int vb2_fop_release(struct file *file) +int __vb2_fop_release(struct file *file, bool lock_is_held) { struct video_device *vdev = video_devdata(file); + struct mutex *lock; if (file->private_data == vdev->queue->owner) { + if (lock_is_held) + lock = NULL; + else + lock = vdev->queue->lock ? + vdev->queue->lock : vdev->lock; + if (lock) + mutex_lock(lock); vb2_queue_release(vdev->queue); vdev->queue->owner = NULL; + if (lock) + mutex_unlock(lock); } return v4l2_fh_release(file); } +EXPORT_SYMBOL_GPL(__vb2_fop_release); + +int vb2_fop_release(struct file *file) +{ + return __vb2_fop_release(file, false); +} EXPORT_SYMBOL_GPL(vb2_fop_release); ssize_t vb2_fop_write(struct file *file, char __user *buf, diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index 6781258..cd1e4d5 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -491,6 +491,8 @@ int vb2_ioctl_expbuf(struct file *file, void *priv, int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma); int vb2_fop_release(struct file *file); +/* must be used if the lock is held. */ +int __vb2_fop_release(struct file *file, bool lock_is_held); ssize_t vb2_fop_write(struct file *file, char __user *buf, size_t count, loff_t *ppos); ssize_t vb2_fop_read(struct file *file, char __user *buf,