[{"id":4818,"web_url":"https://patchwork.libcamera.org/comment/4818/","msgid":"<7bd7cc51-f5bf-6e14-750d-589e7a2ac314@ideasonboard.com>","date":"2020-05-14T09:15:01","subject":"Re: [libcamera-devel] [PATCH v2] libcamera: v4l2_videodevice: Fix\n\tdangling file descriptor","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Hi Naush,\n\nOn 14/05/2020 09:40, Naushir Patuck wrote:\n> The FileDescriptor constructor used in V4L2VideoDevice::exportDmabufFd()\n> creates a duplicate of the fd to store in the object. The original\n> fd returned by the VIDIOC_EXPBUF ioctl was never closed, and left\n> dangling. This would cause out of memory conditions if the camera stream\n> was repeatedly started and stopped.\n> \n> This change closes the original fd explicitly, fixing the leak.\n> \n\nOuch.\n\nAnd agreed,\n\nReviewed-by: Kieran Bingham \n\n\n> Signed-off-by: Naushir Patuck \n> ---\n> src/libcamera/v4l2_videodevice.cpp | 9 ++++++++-\n> 1 file changed, 8 insertions(+), 1 deletion(-)\n> \n> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp\n> index 4b9f8b5c..2f9c1333 100644\n> --- a/src/libcamera/v4l2_videodevice.cpp\n> +++ b/src/libcamera/v4l2_videodevice.cpp\n> @@ -1276,7 +1276,14 @@ FileDescriptor V4L2VideoDevice::exportDmabufFd(unsigned int index,\n> \t\treturn FileDescriptor();\n> \t}\n> \n> -\treturn FileDescriptor(expbuf.fd);\n> +\tFileDescriptor fd(expbuf.fd);\n> +\t/*\n> +\t * FileDescriptor takes a duplicate of fd, so we must close the\n> +\t * original here, otherwise it will be left dangling.\n> +\t */\n> +\t::close(expbuf.fd);\n> +\n> +\treturn fd;\n> }\n> \n> /**\n>","headers":{"Return-Path":"","Received":["from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 49FA460DE6\n\tfor ;\n\tThu, 14 May 2020 11:15:05 +0200 (CEST)","from [192.168.0.20]\n\t(cpc89242-aztw30-2-0-cust488.18-1.cable.virginm.net [86.31.129.233])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id B480F9A8;\n\tThu, 14 May 2020 11:15:04 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"QZTGIwUg\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1589447704;\n\tbh=rgDbpwOLPTnBOeVTjGfNDS+ztCBpsD5oYmhlmOSLIRA=;\n\th=Reply-To:Subject:To:References:From:Date:In-Reply-To:From;\n\tb=QZTGIwUgJH5assXNqL0zH9jGVL8BNFqJLonMPdtxVC04FJ8o2fjBXq3/FCwT3eZhz\n\tVCIY8US8uOEYFzhj4WAmnd1EuNYb29CR3ks/7iB1yLaFHEWiWTG90AeaUDFxlddSiG\n\tQIb4xJz2OSsFbY1Z/quXAEObdjOlIGnfAv1xlUrI=","Reply-To":"kieran.bingham@ideasonboard.com","To":"Naushir Patuck ,\n\tlibcamera-devel@lists.libcamera.org","References":"<20200514084003.16948-1-naush@raspberrypi.com>","From":"Kieran Bingham ","Autocrypt":"addr=kieran.bingham@ideasonboard.com; keydata=\n\tmQINBFYE/WYBEACs1PwjMD9rgCu1hlIiUA1AXR4rv2v+BCLUq//vrX5S5bjzxKAryRf0uHat\n\tV/zwz6hiDrZuHUACDB7X8OaQcwhLaVlq6byfoBr25+hbZG7G3+5EUl9cQ7dQEdvNj6V6y/SC\n\trRanWfelwQThCHckbobWiQJfK9n7rYNcPMq9B8e9F020LFH7Kj6YmO95ewJGgLm+idg1Kb3C\n\tpotzWkXc1xmPzcQ1fvQMOfMwdS+4SNw4rY9f07Xb2K99rjMwZVDgESKIzhsDB5GY465sCsiQ\n\tcSAZRxqE49RTBq2+EQsbrQpIc8XiffAB8qexh5/QPzCmR4kJgCGeHIXBtgRj+nIkCJPZvZtf\n\tKr2EAbc6tgg6DkAEHJb+1okosV09+0+TXywYvtEop/WUOWQ+zo+Y/OBd+8Ptgt1pDRyOBzL8\n\tRXa8ZqRf0Mwg75D+dKntZeJHzPRJyrlfQokngAAs4PaFt6UfS+ypMAF37T6CeDArQC41V3ko\n\tlPn1yMsVD0p+6i3DPvA/GPIksDC4owjnzVX9kM8Zc5Cx+XoAN0w5Eqo4t6qEVbuettxx55gq\n\t8K8FieAjgjMSxngo/HST8TpFeqI5nVeq0/lqtBRQKumuIqDg+Bkr4L1V/PSB6XgQcOdhtd36\n\tOe9X9dXB8YSNt7VjOcO7BTmFn/Z8r92mSAfHXpb07YJWJosQOQARAQABtDBLaWVyYW4gQmlu\n\tZ2hhbSA8a2llcmFuLmJpbmdoYW1AaWRlYXNvbmJvYXJkLmNvbT6JAlcEEwEKAEECGwMFCwkI\n\tBwIGFQgJCgsCBBYCAwECHgECF4ACGQEWIQSQLdeYP70o/eNy1HqhHkZyEKRh/QUCXWTtygUJ\n\tCyJXZAAKCRChHkZyEKRh/f8dEACTDsbLN2nioNZMwyLuQRUAFcXNolDX48xcUXsWS2QjxaPm\n\tVsJx8Uy8aYkS85mdPBh0C83OovQR/OVbr8AxhGvYqBs3nQvbWuTl/+4od7DfK2VZOoKBAu5S\n\tQK2FYuUcikDqYcFWJ8DQnubxfE8dvzojHEkXw0sA4igINHDDFX3HJGZtLio+WpEFQtCbfTAG\n\tYZslasz1YZRbwEdSsmO3/kqy5eMnczlm8a21A3fKUo3g8oAZEFM+f4DUNzqIltg31OAB/kZS\n\tenKZQ/SWC8PmLg/ZXBrReYakxXtkP6w3FwMlzOlhGxqhIRNiAJfXJBaRhuUWzPOpEDE9q5YJ\n\tBmqQL2WJm1VSNNVxbXJHpaWMH1sA2R00vmvRrPXGwyIO0IPYeUYQa3gsy6k+En/aMQJd27dp\n\taScf9am9PFICPY5T4ppneeJLif2lyLojo0mcHOV+uyrds9XkLpp14GfTkeKPdPMrLLTsHRfH\n\tfA4I4OBpRrEPiGIZB/0im98MkGY/Mu6qxeZmYLCcgD6qz4idOvfgVOrNh+aA8HzIVR+RMW8H\n\tQGBN9f0E3kfwxuhl3omo6V7lDw8XOdmuWZNC9zPq1UfryVHANYbLGz9KJ4Aw6M+OgBC2JpkD\n\thXMdHUkC+d20dwXrwHTlrJi1YNp6rBc+xald3wsUPOZ5z8moTHUX/uPA/qhGsbkCDQRWBP1m\n\tARAAzijkb+Sau4hAncr1JjOY+KyFEdUNxRy+hqTJdJfaYihxyaj0Ee0P0zEi35CbE6lgU0Uz\n\ttih9fiUbSV3wfsWqg1Ut3/5rTKu7kLFp15kF7eqvV4uezXRD3Qu4yjv/rMmEJbbD4cTvGCYI\n\td6MDC417f7vK3hCbCVIZSp3GXxyC1LU+UQr3fFcOyCwmP9vDUR9JV0BSqHHxRDdpUXE26Dk6\n\tmhf0V1YkspE5St814ETXpEus2urZE5yJIUROlWPIL+hm3NEWfAP06vsQUyLvr/GtbOT79vXl\n\tEn1aulcYyu20dRRxhkQ6iILaURcxIAVJJKPi8dsoMnS8pB0QW12AHWuirPF0g6DiuUfPmrA5\n\tPKe56IGlpkjc8cO51lIxHkWTpCMWigRdPDexKX+Sb+W9QWK/0JjIc4t3KBaiG8O4yRX8ml2R\n\t+rxfAVKM6V769P/hWoRGdgUMgYHFpHGSgEt80OKK5HeUPy2cngDUXzwrqiM5Sz6Od0qw5pCk\n\tNlXqI0W/who0iSVM+8+RmyY0OEkxEcci7rRLsGnM15B5PjLJjh1f2ULYkv8s4SnDwMZ/kE04\n\t/UqCMK/KnX8pwXEMCjz0h6qWNpGwJ0/tYIgQJZh6bqkvBrDogAvuhf60Sogw+mH8b+PBlx1L\n\toeTK396wc+4c3BfiC6pNtUS5GpsPMMjYMk7kVvEAEQEAAYkCPAQYAQoAJgIbDBYhBJAt15g/\n\tvSj943LUeqEeRnIQpGH9BQJdizzIBQkLSKZiAAoJEKEeRnIQpGH9eYgQAJpjaWNgqNOnMTmD\n\tMJggbwjIotypzIXfhHNCeTkG7+qCDlSaBPclcPGYrTwCt0YWPU2TgGgJrVhYT20ierN8LUvj\n\t6qOPTd+Uk7NFzL65qkh80ZKNBFddx1AabQpSVQKbdcLb8OFs85kuSvFdgqZwgxA1vl4TFhNz\n\tPZ79NAmXLackAx3sOVFhk4WQaKRshCB7cSl+RIng5S/ThOBlwNlcKG7j7W2MC06BlTbdEkUp\n\tECzuuRBv8wX4OQl+hbWbB/VKIx5HKlLu1eypen/5lNVzSqMMIYkkZcjV2SWQyUGxSwq0O/sx\n\tS0A8/atCHUXOboUsn54qdxrVDaK+6jIAuo8JiRWctP16KjzUM7MO0/+4zllM8EY57rXrj48j\n\tsbEYX0YQnzaj+jO6kJtoZsIaYR7rMMq9aUAjyiaEZpmP1qF/2sYenDx0Fg2BSlLvLvXM0vU8\n\tpQk3kgDu7kb/7PRYrZvBsr21EIQoIjXbZxDz/o7z95frkP71EaICttZ6k9q5oxxA5WC6sTXc\n\tMW8zs8avFNuA9VpXt0YupJd2ijtZy2mpZNG02fFVXhIn4G807G7+9mhuC4XG5rKlBBUXTvPU\n\tAfYnB4JBDLmLzBFavQfvonSfbitgXwCG3vS+9HEwAjU30Bar1PEOmIbiAoMzuKeRm2LVpmq4\n\tWZw01QYHU/GUV/zHJSFk","Organization":"Ideas on Board","Message-ID":"<7bd7cc51-f5bf-6e14-750d-589e7a2ac314@ideasonboard.com>","Date":"Thu, 14 May 2020 10:15:01 +0100","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101\n\tThunderbird/68.7.0","MIME-Version":"1.0","In-Reply-To":"<20200514084003.16948-1-naush@raspberrypi.com>","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-GB","Content-Transfer-Encoding":"7bit","Subject":"Re: [libcamera-devel] [PATCH v2] libcamera: v4l2_videodevice: Fix\n\tdangling file descriptor","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","X-List-Received-Date":"Thu, 14 May 2020 09:15:05 -0000"}},{"id":4835,"web_url":"https://patchwork.libcamera.org/comment/4835/","msgid":"<20200518114057.GA5851@pendragon.ideasonboard.com>","date":"2020-05-18T11:40:57","subject":"Re: [libcamera-devel] [PATCH v2] libcamera: v4l2_videodevice: Fix\n\tdangling file descriptor","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Naush,\n\nThank you for the patch.\n\nOn Thu, May 14, 2020 at 09:40:03AM +0100, Naushir Patuck wrote:\n> The FileDescriptor constructor used in V4L2VideoDevice::exportDmabufFd()\n> creates a duplicate of the fd to store in the object. The original\n> fd returned by the VIDIOC_EXPBUF ioctl was never closed, and left\n> dangling. This would cause out of memory conditions if the camera stream\n> was repeatedly started and stopped.\n> \n> This change closes the original fd explicitly, fixing the leak.\n> \n> Signed-off-by: Naushir Patuck \n\nReviewed-by: Laurent Pinchart \n\nand applied.\n\nThis issue however shows that the FileDescriptor class API is not ideal.\nI'll propose enhancements and CC you.\n\n> ---\n> src/libcamera/v4l2_videodevice.cpp | 9 ++++++++-\n> 1 file changed, 8 insertions(+), 1 deletion(-)\n> \n> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp\n> index 4b9f8b5c..2f9c1333 100644\n> --- a/src/libcamera/v4l2_videodevice.cpp\n> +++ b/src/libcamera/v4l2_videodevice.cpp\n> @@ -1276,7 +1276,14 @@ FileDescriptor V4L2VideoDevice::exportDmabufFd(unsigned int index,\n> \t\treturn FileDescriptor();\n> \t}\n> \n> -\treturn FileDescriptor(expbuf.fd);\n> +\tFileDescriptor fd(expbuf.fd);\n> +\t/*\n> +\t * FileDescriptor takes a duplicate of fd, so we must close the\n> +\t * original here, otherwise it will be left dangling.\n> +\t */\n> +\t::close(expbuf.fd);\n> +\n> +\treturn fd;\n> }\n> \n> /**","headers":{"Return-Path":"","Received":["from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 1F9EE603DA\n\tfor ;\n\tMon, 18 May 2020 13:41:06 +0200 (CEST)","from pendragon.ideasonboard.com (81-175-216-236.bb.dnainternet.fi\n\t[81.175.216.236])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 54ADD258;\n\tMon, 18 May 2020 13:41:05 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"CP4G8Egg\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1589802065;\n\tbh=XqnkG4J79Wi24TGIyQWwma2Y3cR8rEfFTZuPoAock3Y=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=CP4G8EggejIDblRd2yuuupA1qSOK0cf5cLNkRNIrbbv9uBPgBRqScBcML/NvAzjh6\n\tM1vUVsmnxTpy9n/mrkF5fOL6OrJopToXetiRRSxCTdqJZZ4he2mQL0cg4KttQ0zbvy\n\txNJEsmFh2JesjAAWWKUDEZjXJEen+W5zDubin7/w=","Date":"Mon, 18 May 2020 14:40:57 +0300","From":"Laurent Pinchart ","To":"Naushir Patuck ","Cc":"libcamera-devel@lists.libcamera.org","Message-ID":"<20200518114057.GA5851@pendragon.ideasonboard.com>","References":"<20200514084003.16948-1-naush@raspberrypi.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20200514084003.16948-1-naush@raspberrypi.com>","Subject":"Re: [libcamera-devel] [PATCH v2] libcamera: v4l2_videodevice: Fix\n\tdangling file descriptor","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","X-List-Received-Date":"Mon, 18 May 2020 11:41:06 -0000"}}]