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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6mBb4/iuC0fdFhL9tw09XYFkyqp3sb1uhjQN2YXG8WoKsmsbtSEfqVy8JeSy?= =?us-ascii?Q?abDUpJvjCpyQ2cMDllU1eUPWIAi0uo+kybH7EaNTni0K4UARFAcqrQ6mjMRP?= =?us-ascii?Q?K0NZJuYy3bC2QnxD0zpqyPRuKftM35jz2rSRxDOArHx58H+Nju1YMWieO9JP?= =?us-ascii?Q?Ie3kwVg3470VHS7ChJYxNVnbB2tknFRJlOJXw1L1hV17GuDcjubrS/lsSZxB?= =?us-ascii?Q?9IWtf8Pw8lQqVGYU8o/xTliQ4FQcKTfZ5khTQYeQEGw2KJaCLOhjyuzbf536?= =?us-ascii?Q?YfrqXcehZLZ4wdGMIFW6uYH2vxgbRn+Y9VFCuNDluvPK9qrRPPWo5/hwxWrJ?= =?us-ascii?Q?ALBcjkyjzK8LSSh4qbsW5L/LkJOC/rxaYo0YxW9sLFNJCHcU7csdE//Tia7O?= =?us-ascii?Q?w8PUrAQ5wOAouQFZ0z1XMMSYP/TEyRRvOD4to79ye+n60OcmSc01dxOjqUU9?= =?us-ascii?Q?rhD9R4Xt0ZrNw4BO5Qt/9GivyHHnUX2X5y4F7zoJ3qbZE2yMMaoq5txZJkBh?= =?us-ascii?Q?8wwyokRt8I+ZHSN2joPEKF1FjyLw+S5sBzLxixT8QUL7A4U3BYznZcKcQlcb?= =?us-ascii?Q?zBxA/lu+ml46tH0jMeo1o+dR3yQacLREsWUcS3tSNMU83DKJimcCzMkjEbzt?= =?us-ascii?Q?xCrjK85xAH7JT4a5CGtW7yHEM73Zp48pfiKRKFS6yIohacDdwlyf++xn7I4z?= =?us-ascii?Q?PknQAicFyB4ITBYrmbSoFjz0cmNydStAOl3GaZuG1Ut8XJYFTpVrZ8XvSFQs?= =?us-ascii?Q?bzCCTjhYlOe+pfpYv/I3QUvfYg2wKSIR4jbGixJ6ITb2whpsUz58StCxQud2?= =?us-ascii?Q?l/ybdbfscgC2nb7r7OGk/umf0TjejsDIutgH58iwadXLyPyaroYdF3QJs+o0?= =?us-ascii?Q?jiWjc5NpkkFFdPZRYfGx349I/mNqV+Z1n/9O6p2Z2tfBIhvYlktFgGrE+qNx?= =?us-ascii?Q?VI6fMPDUXUQxb+HlvD/PrafFBGRW9TzH/sf19MMFVH6dd8C6O9C7uzg3Tr8b?= =?us-ascii?Q?JswglgaKnFI6e5fyl+NHsxrbndO7QfWe2jWTcCm4ZYoqSsACTG9bGADj4+dH?= =?us-ascii?Q?rZaPTexfHwybfs/i/YkMDxf1/lhgR7bRB8lzB9F0mjZhk6ZhtlUmJC+jQL3e?= =?us-ascii?Q?uS2+iC8xflAQfY3MYOlK3w4Ty7GoOSO/ex2o7R+EwR9yeMjfN/Bpl7uJ5uRL?= =?us-ascii?Q?ZDIu+yLRL++mee0/0tMtVDD6SKK1xyGlJmdowWdCpWch8p1A0iwVyCeKGQTu?= =?us-ascii?Q?hQfLIVRS37FnOpQDtZV2MqVe1n6TEK9tBAxCz4RKV7Tr9IzmgklzlC3koy4r?= =?us-ascii?Q?OxnSInB24WCBnJbynXaeUqYOqvJDFCoA2fjbRoBdkPch1sBS3aYrQRpnxjmd?= =?us-ascii?Q?efNNpkz0W0r7aXef1HoT+0Pu9dHDQbX4WPLyKoo5F63Jslhzr82lXZD86D85?= =?us-ascii?Q?Vfrneavdfd3m8/ys4uXXn6PjwPKYGXXurkIMxxm5JMJEMJLwkA1IbBoaCn6l?= =?us-ascii?Q?NsTMcRGoumifqdM3DnoT/5m0v82IJ+FYtmDnyu0CZLYmuetiQGjGGQEUKwRr?= =?us-ascii?Q?uu4l2xDMR0hqn61XT3ElBNfQ7gzRNGiI6djjNyCp?= X-OriginatorOrg: labundy.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9a0cb9c8-72d2-4718-04b3-08dcbf493beb X-MS-Exchange-CrossTenant-AuthSource: BN7PR08MB3937.namprd08.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Aug 2024 05:47:27.2349 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 00b69d09-acab-4585-aca7-8fb7c6323e6f X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: GqR5t7oUSbFY1tQc14a0soUj4RlPWeulYWpPp8ufD1AslQE8D6GO7a10Om5QPYkcocAnYbVPL23chTbNmMlltw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR08MB7164 Hi Dmitry, On Thu, Aug 15, 2024 at 11:41:53AM -0700, Dmitry Torokhov wrote: > Limit amount of data that can be written into an evdev instance at > a given time to 4096 bytes (170 input events) to avoid holding > evdev->mutex for too long and starving other users. > > Signed-off-by: Dmitry Torokhov Reviewed-by: Jeff LaBundy > --- > drivers/input/evdev.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c > index a8ce3d140722..eb4906552ac8 100644 > --- a/drivers/input/evdev.c > +++ b/drivers/input/evdev.c > @@ -498,6 +498,13 @@ static ssize_t evdev_write(struct file *file, const char __user *buffer, > struct input_event event; > int retval = 0; > > + /* > + * Limit amount of data we inject into the input subsystem so that > + * we do not hold evdev->mutex for too long. 4096 bytes corresponds > + * to 170 input events. > + */ > + count = min(count, 4096); > + > if (count != 0 && count < input_event_size()) > return -EINVAL; > > -- > 2.46.0.184.g6999bdac58-goog > > > -- > Dmitry Kind regards, Jeff LaBundy