On Sun, Oct 16, 2022 at 09:36:50PM -0700, Kees Cook wrote: > The 'nfs_server' and 'mount_server' structures include a union of > 'struct sockaddr' (with the older 16 bytes max address size) and > 'struct sockaddr_storage' which is large enough to hold all the > supported sa_family types (128 bytes max size). The runtime memcpy() > buffer overflow checker is seeing attempts to write beyond the 16 > bytes as an overflow, but the actual expected size is that of 'struct > sockaddr_storage'. Plumb the use of 'struct sockaddr_storage' more > completely through-out NFS, which results in adjusting the memcpy() > buffers to the correct union members. Avoids this false positive run-time > warning under CONFIG_FORTIFY_SOURCE: > > memcpy: detected field-spanning write (size 28) of single field "&ctx->nfs_server.address" at fs/nfs/namespace.c:178 (size 16) > > Reported-by: kernel test robot <yujie.liu@xxxxxxxxx> > Link: https://lore.kernel.org/all/202210110948.26b43120-yujie.liu@xxxxxxxxx > Cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> > Cc: Anna Schumaker <anna@xxxxxxxxxx> Friendly ping -- this needs to land in v6.1 to avoid these warnings. Should I carry this in the hardening tree instead? Thanks! -Kees -- Kees Cook
