Merge tag '9p-for-5.4' of git://github.com/martinetd/linux

Pull 9p updates from Dominique Martinet:
 "Some of the usual small fixes and cleanup.

  Small fixes all around:
   - avoid overlayfs copy-up for PRIVATE mmaps
   - KUMSAN uninitialized warning for transport error
   - one syzbot memory leak fix in 9p cache
   - internal API cleanup for v9fs_fill_super"

* tag '9p-for-5.4' of git://github.com/martinetd/linux:
  9p/vfs_super.c: Remove unused parameter data in v9fs_fill_super
  9p/cache.c: Fix memory leak in v9fs_cache_session_get_cookie
  9p: Transport error uninitialized
  9p: avoid attaching writeback_fid on mmap with type PRIVATE

3 files changed, 7 insertions, 2 deletions

diff --git a/fs/9p/cache.c b/fs/9p/cache.c
index 995e332eee5c..eb2151fb6049 100644
--- a/fs/9p/cache.c
+++ b/fs/9p/cache.c
@@ -51,6 +51,8 @@ void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
 	if (!v9ses->cachetag) {
 		if (v9fs_random_cachetag(v9ses) < 0) {
 			v9ses->fscache = NULL;
+			kfree(v9ses->cachetag);
+			v9ses->cachetag = NULL;
 			return;
 		}
 	}
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 4cc966a31cb3..fe7f0bd2048e 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -513,6 +513,7 @@ v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
 	v9inode = V9FS_I(inode);
 	mutex_lock(&v9inode->v_mutex);
 	if (!v9inode->writeback_fid &&
+	    (vma->vm_flags & VM_SHARED) &&
 	    (vma->vm_flags & VM_WRITE)) {
 		/*
 		 * clone a fid and add it to writeback_fid
@@ -614,6 +615,8 @@ static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
 			(vma->vm_end - vma->vm_start - 1),
 	};
 
+	if (!(vma->vm_flags & VM_SHARED))
+		return;
 
 	p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
 
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index ca243e658d71..74df32be4c6a 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -58,7 +58,7 @@ static int v9fs_set_super(struct super_block *s, void *data)
 
 static int
 v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
-		int flags, void *data)
+		int flags)
 {
 	int ret;
 
@@ -132,7 +132,7 @@ static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags,
 		retval = PTR_ERR(sb);
 		goto clunk_fid;
 	}
-	retval = v9fs_fill_super(sb, v9ses, flags, data);
+	retval = v9fs_fill_super(sb, v9ses, flags);
 	if (retval)
 		goto release_sb;