| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.4 088/214] nfsd4: fix xdr decoding of large non-write compounds | Date | Wed, 4 Jun 2014 21:17:31 -0700 |
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3.4-stable review patch. If anyone has any objections, please let me know.
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From: "J. Bruce Fields" <bfields@redhat.com>
commit 365da4adebb1c012febf81019ad3dc5bb52e2a13 upstream.
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.
Signed-off-by: J. Bruce Fields <bfields@redhat.com> [bwh: Backported to 3.2: adjust context; there is only one instance to fix] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Rui Xiang <rui.xiang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- fs/nfsd/nfs4xdr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -161,8 +161,8 @@ static __be32 *read_buf(struct nfsd4_com */ memcpy(p, argp->p, avail); /* step to next page */ - 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;
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