From: Chuck Lever <chuck.lever@xxxxxxxxxx>
There's no guarantee that the pointer returned from
xdr_reserve_space() will still point to the correct reserved space
in the encode buffer after one or more intervening calls to
xdr_reserve_space(). It just happens to work with the current
implementation of xdr_reserve_space().
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
fs/nfsd/nfs4xdr.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index a8b99e4796c9..348cd13f9012 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -4642,13 +4642,13 @@ nfsd4_encode_secinfo4(struct xdr_stream *xdr, rpc_authflavor_t pf,
}
static __be32
-nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
+nfsd4_encode_SECINFO4resok(struct xdr_stream *xdr, struct svc_export *exp)
{
u32 i, nflavs, supported;
struct exp_flavor_info *flavs;
struct exp_flavor_info def_flavs[2];
- __be32 *flavorsp;
- __be32 status;
+ unsigned int count_offset;
+ __be32 status, wire_count;
if (exp->ex_nflavors) {
flavs = exp->ex_flavors;
@@ -4670,8 +4670,8 @@ nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
}
}
- flavorsp = xdr_reserve_space(xdr, XDR_UNIT);
- if (!flavorsp)
+ count_offset = xdr_stream_pos(xdr);
+ if (unlikely(!xdr_reserve_space(xdr, XDR_UNIT)))
return nfserr_resource;
for (i = 0, supported = 0; i < nflavs; i++) {
@@ -4681,7 +4681,9 @@ nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
return status;
}
- *flavorsp = cpu_to_be32(supported);
+ wire_count = cpu_to_be32(supported);
+ write_bytes_to_xdr_buf(xdr->buf, count_offset, &wire_count,
+ XDR_UNIT);
return 0;
}
@@ -4692,7 +4694,7 @@ nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
struct nfsd4_secinfo *secinfo = &u->secinfo;
struct xdr_stream *xdr = resp->xdr;
- return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
+ return nfsd4_encode_SECINFO4resok(xdr, secinfo->si_exp);
}
static __be32
@@ -4702,7 +4704,7 @@ nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
struct nfsd4_secinfo_no_name *secinfo = &u->secinfo_no_name;
struct xdr_stream *xdr = resp->xdr;
- return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
+ return nfsd4_encode_SECINFO4resok(xdr, secinfo->sin_exp);
}
static __be32
--
2.47.0
