diff options
| author | Muhammad Usama Anjum <usama.anjum@collabora.com> | 2023-12-14 15:19:30 +0500 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-12-20 13:46:19 -0800 |
| commit | 0aac13add26d546ac74c89d2883b3a5f0fbea039 (patch) | |
| tree | 2de5bba3ac65e43188cc45fced5b6196afc2eca2 /tools | |
| parent | fc346d0a70a13d52fe1c4bc49516d83a42cd7c4c (diff) | |
selftests: secretmem: floor the memory size to the multiple of page_size
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.
This was getting triggered on KernelCI regularly because of different
ulimit settings which wasn't multiple of the page_size. Find logs
here: https://linux.kernelci.org/test/plan/id/657654bd8e81e654fae13532/
The bug in was present from the time test was first added.
Link: https://lkml.kernel.org/r/20231214101931.1155586-1-usama.anjum@collabora.com
Fixes: 76fe17ef588a ("secretmem: test: add basic selftest for memfd_secret(2)")
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Closes: https://linux.kernelci.org/test/plan/id/657654bd8e81e654fae13532/
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/testing/selftests/mm/memfd_secret.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/memfd_secret.c b/tools/testing/selftests/mm/memfd_secret.c index 957b9e18c729..9b298f6a04b3 100644 --- a/tools/testing/selftests/mm/memfd_secret.c +++ b/tools/testing/selftests/mm/memfd_secret.c @@ -62,6 +62,9 @@ static void test_mlock_limit(int fd) char *mem; len = mlock_limit_cur; + if (len % page_size != 0) + len = (len/page_size) * page_size; + mem = mmap(NULL, len, prot, mode, fd, 0); if (mem == MAP_FAILED) { fail("unable to mmap secret memory\n"); |