From 78d04af4995a1358039f4406bd31c28faedfa030 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 20 Sep 2016 14:34:24 -0400 Subject: [PATCH] NFS: nfs_prime_dcache must validate the filename Before we try to stash it in the dcache, we need to at least check that the filename passed to us by the server is non-empty and doesn't contain any illegal '\0' or '/' characters. Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker --- fs/nfs/dir.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 177fefb26c18..eb095f77c39d 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -496,6 +496,14 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry) return; if (!(entry->fattr->valid & NFS_ATTR_FATTR_FSID)) return; + if (filename.len == 0) + return; + /* Validate that the name doesn't contain any illegal '\0' */ + if (strnlen(filename.name, filename.len) != filename.len) + return; + /* ...or '/' */ + if (strnchr(filename.name, filename.len, '/')) + return; if (filename.name[0] == '.') { if (filename.len == 1) return; -- 2.20.1