Re: [PATCH] acpi: fix a potential inconsistency caused by double-fetch

Hi Kangjie, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on pm/linux-next] [also build test WARNING on v4.20 next-20181224] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/l

Re: [PATCH] acpi: fix a potential inconsistency caused by double-fetch

Hi Kangjie, Thank you for the patch! Yet something to improve: [auto build test ERROR on pm/linux-next] [also build test ERROR on v4.20 next-20181224] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/com

[PATCH] acpi: fix a potential inconsistency caused by double-fetch

"user_buf->length" is in user space, and copied in twice. The second copy is after it passes the security check. If a user program races to change user_buf->length in user space, the data fetched in the second copy may invalidate the security check. The fix avoids the double-fetch issue by using th