diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c index 971a9251c1d9..902db1262d2b 100644 --- a/fs/nfs/fs_context.c +++ b/fs/nfs/fs_context.c @@ -973,6 +973,15 @@ static int nfs23_parse_monolithic(struct fs_context *fc, memset(mntfh->data + mntfh->size, 0, sizeof(mntfh->data) - mntfh->size); + /* + * for proto == XPRT_TRANSPORT_UDP, which is what uses + * to_exponential, implying shift: limit the shift value + * to BITS_PER_LONG (majortimeo is unsigned long) + */ + if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */ + if (data->retrans >= 64) /* shift value is too large */ + goto out_invalid_data; + /* * Translate to nfs_fs_context, which nfs_fill_super * can deal with. @@ -1073,6 +1082,9 @@ static int nfs23_parse_monolithic(struct fs_context *fc, out_invalid_fh: return nfs_invalf(fc, "NFS: invalid root filehandle"); + +out_invalid_data: + return nfs_invalf(fc, "NFS: invalid binary mount data"); } #if IS_ENABLED(CONFIG_NFS_V4)