From: Chuck Lever chuck.lever@oracle.com
commit 6260d9a56ab352b54891ec66ab0eced57d55abc6 upstream.
Ensure that a client cannot specify a WRITE range that falls in a byte range outside what the kernel's internal types (such as loff_t, which is signed) can represent. The kiocb iterators, invoked in nfsd_vfs_write(), should properly limit write operations to within the underlying file system's s_maxbytes.
Cc: stable@vger.kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/nfs3proc.c | 5 +++++ fs/nfsd/nfs4proc.c | 5 +++-- 2 files changed, 8 insertions(+), 2 deletions(-)
--- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -183,6 +183,11 @@ nfsd3_proc_write(struct svc_rqst *rqstp) (unsigned long long) argp->offset, argp->stable? " stable" : "");
+ resp->status = nfserr_fbig; + if (argp->offset > (u64)OFFSET_MAX || + argp->offset + argp->len > (u64)OFFSET_MAX) + return rpc_success; + fh_copy(&resp->fh, &argp->fh); resp->committed = argp->stable; nvecs = svc_fill_write_vector(rqstp, rqstp->rq_arg.pages, --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1008,8 +1008,9 @@ nfsd4_write(struct svc_rqst *rqstp, stru unsigned long cnt; int nvecs;
- if (write->wr_offset >= OFFSET_MAX) - return nfserr_inval; + if (write->wr_offset > (u64)OFFSET_MAX || + write->wr_offset + write->wr_buflen > (u64)OFFSET_MAX) + return nfserr_fbig;
cnt = write->wr_buflen; trace_nfsd_write_start(rqstp, &cstate->current_fh,