From ef95d31e6de6be9602ce950b85fb7ab8af46ae42 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 10 Mar 2009 20:33:17 -0400 Subject: [PATCH] NFS: Fix misparsing of nfsv4 fs_locations attribute (take 2) The changeset ea31a4437c59219bf3ea946d58984b01a45a289c (nfs: Fix misparsing of nfsv4 fs_locations attribute) causes the mountpath that is calculated at the beginning of try_location() to be clobbered when we later strncpy a non-nul terminated hostname using an incorrect buffer length. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4namespace.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index 30befc39b3c..2a2a0a7143a 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -21,7 +21,9 @@ #define NFSDBG_FACILITY NFSDBG_VFS /* - * Check if fs_root is valid + * Convert the NFSv4 pathname components into a standard posix path. + * + * Note that the resulting string will be placed at the end of the buffer */ static inline char *nfs4_pathname_string(const struct nfs4_pathname *pathname, char *buffer, ssize_t buflen) @@ -99,21 +101,20 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata, { struct vfsmount *mnt = ERR_PTR(-ENOENT); char *mnt_path; - int page2len; + unsigned int maxbuflen; unsigned int s; mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE); if (IS_ERR(mnt_path)) return mnt; mountdata->mnt_path = mnt_path; - page2 += strlen(mnt_path) + 1; - page2len = PAGE_SIZE - strlen(mnt_path) - 1; + maxbuflen = mnt_path - 1 - page2; for (s = 0; s < location->nservers; s++) { const struct nfs4_string *buf = &location->servers[s]; struct sockaddr_storage addr; - if (buf->len <= 0 || buf->len >= PAGE_SIZE) + if (buf->len <= 0 || buf->len >= maxbuflen) continue; mountdata->addr = (struct sockaddr *)&addr; @@ -126,8 +127,8 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata, continue; nfs_set_port(mountdata->addr, NFS_PORT); - strncpy(page2, buf->data, page2len); - page2[page2len] = '\0'; + memcpy(page2, buf->data, buf->len); + page2[buf->len] = '\0'; mountdata->hostname = page2; snprintf(page, PAGE_SIZE, "%s:%s", -- 2.41.0