[PATCH v1 33/42] NFSD: Remove argument length checking in nfsd_dispatch()

Chuck Lever
2021-01-05T15:32:54Z

Now that the argument decoders for NFSv2 and NFSv3 use the
xdr_stream mechanism, the version-specific length checking logic in
nfsd_dispatch() is no longer necessary.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
fs/nfsd/nfssvc.c | 34 ----------------------------------
1 file changed, 34 deletions(-)

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index f9c9f4c63cc7..6de406322106 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -955,37 +955,6 @@ nfsd(void *vrqstp)
return 0;
}

-/*
- * A write procedure can have a large argument, and a read procedure can
- * have a large reply, but no NFSv2 or NFSv3 procedure has argument and
- * reply that can both be larger than a page. The xdr code has taken
- * advantage of this assumption to be a sloppy about bounds checking in
- * some cases. Pending a rewrite of the NFSv2/v3 xdr code to fix that
- * problem, we enforce these assumptions here:
- */
-static bool nfs_request_too_big(struct svc_rqst *rqstp,
- const struct svc_procedure *proc)
-{
- /*
- * The ACL code has more careful bounds-checking and is not
- * susceptible to this problem:
- */
- if (rqstp->rq_prog != NFS_PROGRAM)
- return false;
- /*
- * Ditto NFSv4 (which can in theory have argument and reply both
- * more than a page):
- */
- if (rqstp->rq_vers >= 4)
- return false;
- /* The reply will be small, we're OK: */
- if (proc->pc_xdrressize > 0 &&
- proc->pc_xdrressize < XDR_QUADLEN(PAGE_SIZE))
- return false;
-
- return rqstp->rq_arg.len > PAGE_SIZE;
-}
-
/**
* nfsd_dispatch - Process an NFS or NFSACL Request
* @rqstp: incoming request
@@ -1004,9 +973,6 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
struct kvec *resv = &rqstp->rq_res.head[0];
__be32 *p;

- if (nfs_request_too_big(rqstp, proc))
- goto out_decode_err;
-
/*
* Give the xdr decoder a chance to change this if it wants
* (necessary in the NFSv4.0 compound case)