From: J. Bruce Fields Date: Tue, 19 Nov 2013 22:32:43 +0000 (-0500) Subject: nfsd4: fix xdr decoding of large non-write compounds X-Git-Tag: Ubuntu-5.0.0-8.9~12510^2 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=365da4adebb1c012febf81019ad3dc5bb52e2a13;p=mirror_ubuntu-disco-kernel.git nfsd4: fix xdr decoding of large non-write compounds This fixes a regression from 247500820ebd02ad87525db5d9b199e5b66f6636 "nfsd4: fix decoding of compounds across page boundaries". The previous code was correct: argp->pagelist is initialized in nfs4svc_deocde_compoundargs to rqstp->rq_arg.pages, and is therefore a pointer to the page *after* the page we are currently decoding. The reason that patch nevertheless fixed a problem with decoding compounds containing write was a bug in the write decoding introduced by 5a80a54d21c96590d013378d8c5f65f879451ab4 "nfsd4: reorganize write decoding", after which write decoding no longer adhered to the rule that argp->pagelist point to the next page. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields --- diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 088de1355e93..ee7237f99f54 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -141,8 +141,8 @@ xdr_error: \ static void next_decode_page(struct nfsd4_compoundargs *argp) { - argp->pagelist++; argp->p = page_address(argp->pagelist[0]); + argp->pagelist++; if (argp->pagelen < PAGE_SIZE) { argp->end = argp->p + (argp->pagelen>>2); argp->pagelen = 0; @@ -1229,6 +1229,7 @@ nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write) len -= pages * PAGE_SIZE; argp->p = (__be32 *)page_address(argp->pagelist[0]); + argp->pagelist++; argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE); } argp->p += XDR_QUADLEN(len);