On Thu, 14 Dec 2023 15:19:30 +0500 Muhammad Usama Anjum usama.anjum@collabora.com wrote:
The "locked-in-memory size" limit per process can be non-multiple of page_size. The mmap() fails if we try to allocate locked-in-memory with same size as the allowed limit if it isn't multiple of the page_size because mmap() rounds off the memory size to be allocated to next multiple of page_size.
Fix this by flooring the length to be allocated with mmap() to the previous multiple of the page_size.
I'd like to understand how this was noticed, what the ongoing effect might be, etc. To help decide which kernel version(s) need the patch.
Fixes: 76fe17ef588a ("secretmem: test: add basic selftest for memfd_secret(2)") Reported-by: "kernelci.org bot" bot@kernelci.org
Which is one of the reasons we're now placing a Closes: tag after a Reported-by:.