Changeset 38922 in vbox

Timestamp:

Sep 30, 2011 2:58:49 PM (13 years ago)

Author:

vboxsync

Message:

Additions/solaris/SharedFolders: MMAP fix for non-zero reused pages.

File:

• trunk/src/VBox/Additions/solaris/SharedFolders/vboxfs_vnode.c (modified) (1 diff)

trunk/src/VBox/Additions/solaris/SharedFolders/vboxfs_vnode.c

@@ -1542 +1542 @@
                 uint32_t bytes = PAGESIZE;
                 error = sfprov_read(node->sf_file, virtaddr, io_off, &bytes);
+                /*
+                 * If we reuse pages without zero'ing them, one process can mmap() and read-past the length
+                 * to read previously mmap'd contents (from possibly other processes).
+                 */
+                if (error == 0 && bytes < PAGESIZE)
+                        memset(virtaddr + bytes, 0, PAGESIZE - bytes);
                 sffs_page_unmap(pcur, virtaddr);
                 if (error != 0)