Merge tag 'ntfs-for-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs

Pull ntfs fixes from Namjae Jeon:

 - Keep RECALL_ON_OPEN in inode flags when reloading them from
   $FILE_NAME

 - Check runlist reallocation sizes for negative values and overflow

 - Drop stale page cache after shrinking non-resident attributes to
   prevent writeback failures and data loss

* tag 'ntfs-for-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs:
  ntfs: drop stale page-cache when shrinking a non-resident attr
  ntfs: harden runlist realloc size calculations
  ntfs: preserve RECALL_ON_OPEN on WSL special-file reparse points

3 files changed, 39 insertions, 24 deletions

diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c
index 239b7bcbaedf..58f32aac5f61 100644
--- a/fs/ntfs/attrib.c
+++ b/fs/ntfs/attrib.c
@@ -4293,6 +4293,16 @@ static int ntfs_non_resident_attr_shrink(struct ntfs_inode *ni, const s64 newsiz
 		ni->initialized_size = newsize;
 		ctx->attr->data.non_resident.initialized_size = cpu_to_le64(newsize);
 	}
+
+	/*
+	 * Drop any page-cache folios that now lie beyond the shrunk
+	 * attribute. The clusters backing them have just been freed and the
+	 * runlist truncated, so leaving stale dirty folios around makes a
+	 * later writeback map a vcn past the new allocation, which fails with
+	 * -ENOENT and loses the write.
+	 */
+	truncate_inode_pages(VFS_I(ni)->i_mapping, newsize);
+
 	/* Update data size in the index. */
 	if (ni->type == AT_DATA && ni->name == AT_UNNAMED)
 		NInoSetFileNameDirty(ni);
diff --git a/fs/ntfs/namei.c b/fs/ntfs/namei.c
index 5ff25e9aaa32..cd403b1d99ee 100644
--- a/fs/ntfs/namei.c
+++ b/fs/ntfs/namei.c
@@ -685,7 +685,8 @@ static struct ntfs_inode *__ntfs_create(struct mnt_idmap *idmap, struct inode *d
 	mutex_unlock(&dir_ni->mrec_lock);
 	mutex_unlock(&ni->mrec_lock);
 
-	ni->flags = fn->file_attributes;
+	ni->flags = fn->file_attributes |
+		    (ni->flags & FILE_ATTRIBUTE_RECALL_ON_OPEN);
 	/* Set the sequence number. */
 	vi->i_generation = ni->seq_no;
 	set_nlink(vi, 1);
diff --git a/fs/ntfs/runlist.c b/fs/ntfs/runlist.c
index cbb6576cf725..8e0fd400e7f7 100644
--- a/fs/ntfs/runlist.c
+++ b/fs/ntfs/runlist.c
@@ -71,29 +71,46 @@ static inline void ntfs_rl_mc(struct runlist_element *dstbase, int dst,
  * On success, return a pointer to the newly allocated, or recycled, memory.
  * On error, return -errno.
  */
-struct runlist_element *ntfs_rl_realloc(struct runlist_element *rl,
-		int old_size, int new_size)
+static inline struct runlist_element *ntfs_rl_realloc_gfp(struct runlist_element *rl,
+		int old_size, int new_size, gfp_t gfp)
 {
 	struct runlist_element *new_rl;
+	size_t new_bytes;
+
+	if (old_size < 0 || new_size < 0)
+		return ERR_PTR(-EINVAL);
 
-	old_size = old_size * sizeof(*rl);
-	new_size = new_size * sizeof(*rl);
 	if (old_size == new_size)
 		return rl;
 
-	new_rl = kvzalloc(new_size, GFP_NOFS);
+	if (check_mul_overflow(new_size, sizeof(*rl), &new_bytes))
+		return ERR_PTR(-EINVAL);
+
+	new_rl = kvzalloc(new_bytes, gfp);
 	if (unlikely(!new_rl))
 		return ERR_PTR(-ENOMEM);
 
 	if (likely(rl != NULL)) {
-		if (unlikely(old_size > new_size))
-			old_size = new_size;
-		memcpy(new_rl, rl, old_size);
+		size_t old_bytes;
+
+		if (check_mul_overflow(old_size, sizeof(*rl), &old_bytes)) {
+			kvfree(new_rl);
+			return ERR_PTR(-EINVAL);
+		}
+		if (unlikely(old_bytes > new_bytes))
+			old_bytes = new_bytes;
+		memcpy(new_rl, rl, old_bytes);
 		kvfree(rl);
 	}
 	return new_rl;
 }
 
+struct runlist_element *ntfs_rl_realloc(struct runlist_element *rl,
+		int old_size, int new_size)
+{
+	return ntfs_rl_realloc_gfp(rl, old_size, new_size, GFP_NOFS);
+}
+
 /*
  * ntfs_rl_realloc_nofail - Reallocate memory for runlists
  * @rl:		original runlist
@@ -118,21 +135,8 @@ struct runlist_element *ntfs_rl_realloc(struct runlist_element *rl,
 static inline struct runlist_element *ntfs_rl_realloc_nofail(struct runlist_element *rl,
 		int old_size, int new_size)
 {
-	struct runlist_element *new_rl;
-
-	old_size = old_size * sizeof(*rl);
-	new_size = new_size * sizeof(*rl);
-	if (old_size == new_size)
-		return rl;
-
-	new_rl = kvmalloc(new_size, GFP_NOFS | __GFP_NOFAIL);
-	if (likely(rl != NULL)) {
-		if (unlikely(old_size > new_size))
-			old_size = new_size;
-		memcpy(new_rl, rl, old_size);
-		kvfree(rl);
-	}
-	return new_rl;
+	return ntfs_rl_realloc_gfp(rl, old_size, new_size,
+			GFP_NOFS | __GFP_NOFAIL);
 }
 
 /*