From: Nadav Amit <[email protected]> It is possible to get an EINVAL error instead of EPERM if the following test vm_flags have VM_UFFD_WP but do not have VM_MAYWRITE, as "ret" is overwritten since commit cab350afcbc9 ("userfaultfd: hugetlbfs: allow registration of ranges containing huge pages").
Fix it. Cc: Mike Kravetz <[email protected]> Cc: Jens Axboe <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Peter Xu <[email protected]> Cc: Alexander Viro <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Fixes: cab350afcbc9 ("userfaultfd: hugetlbfs: allow registration of ranges containing huge pages") Signed-off-by: Nadav Amit <[email protected]> --- fs/userfaultfd.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 000b457ad087..c8ed4320370e 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -1364,6 +1364,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx, if (end & (vma_hpagesize - 1)) goto out_unlock; } + ret = -EPERM; if ((vm_flags & VM_UFFD_WP) && !(cur->vm_flags & VM_MAYWRITE)) goto out_unlock; -- 2.25.1
