diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 1ada1c0a728d..849cfd2de705 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -3560,8 +3560,11 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
 	/*
 	 * We zero the range through ioctl, so we need remove the page caches
 	 * first, otherwise the data may be inconsistent with the server.
+	 *
+	 * Start at the old EOF when extending so the folio straddling it, which
+	 * may hold data written past EOF through an mmap, is dropped too.
 	 */
-	truncate_pagecache_range(inode, offset, offset + len - 1);
+	truncate_pagecache_range(inode, min(offset, i_size), offset + len - 1);
 	netfs_wait_for_outstanding_io(inode);
 
 	/* if file not oplocked can't be sure whether asking to extend size */