author: Peter Xu <peterx@redhat.com> 2020-04-06 20:06:20 -0700
committer: Linus Torvalds <torvalds@linux-foundation.org> 2020-04-07 10:43:39 -0700
commit: 23080e2783ba45208795faad124eab0e0bdae85a
parent: e06f1e1dd4998ffc9da37f580703b55a93fc4de4
Commit Summary:
Diffstat:
1 file changed, 6 insertions, 5 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 59e9e399fddb..6e878d23547c 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -1812,6 +1812,7 @@ static int userfaultfd_writeprotect(struct userfaultfd_ctx *ctx,
struct uffdio_writeprotect uffdio_wp;
struct uffdio_writeprotect __user *user_uffdio_wp;
struct userfaultfd_wake_range range;
+ bool mode_wp, mode_dontwake;
if (READ_ONCE(ctx->mmap_changing))
return -EAGAIN;
@@ -1830,18 +1831,20 @@ static int userfaultfd_writeprotect(struct userfaultfd_ctx *ctx,
if (uffdio_wp.mode & ~(UFFDIO_WRITEPROTECT_MODE_DONTWAKE |
UFFDIO_WRITEPROTECT_MODE_WP))
return -EINVAL;
- if ((uffdio_wp.mode & UFFDIO_WRITEPROTECT_MODE_WP) &&
- (uffdio_wp.mode & UFFDIO_WRITEPROTECT_MODE_DONTWAKE))
+
+ mode_wp = uffdio_wp.mode & UFFDIO_WRITEPROTECT_MODE_WP;
+ mode_dontwake = uffdio_wp.mode & UFFDIO_WRITEPROTECT_MODE_DONTWAKE;
+
+ if (mode_wp && mode_dontwake)
return -EINVAL;
ret = mwriteprotect_range(ctx->mm, uffdio_wp.range.start,
- uffdio_wp.range.len, uffdio_wp.mode &
- UFFDIO_WRITEPROTECT_MODE_WP,
+ uffdio_wp.range.len, mode_wp,
&ctx->mmap_changing);
if (ret)
return ret;
- if (!(uffdio_wp.mode & UFFDIO_WRITEPROTECT_MODE_DONTWAKE)) {
+ if (!mode_wp && !mode_dontwake) {
range.start = uffdio_wp.range.start;
range.len = uffdio_wp.range.len;
wake_userfault(ctx, &range);