diff options
| author | J. Bruce Fields <bfields@redhat.com> | 2014-03-06 20:39:29 -0500 |
|---|---|---|
| committer | J. Bruce Fields <bfields@redhat.com> | 2014-05-27 11:09:08 -0400 |
| commit | 07d1f8020738ba3180ea9992c4fa7dbc0685396a (patch) | |
| tree | 3c400bbbe4c453f6b1d5afddf3d7bfae77e81daa /fs | |
| parent | 1802a67894fab3ff90a3ef4f484e97a5b4515426 (diff) | |
| download | linux-07d1f8020738ba3180ea9992c4fa7dbc0685396a.tar.bz2 | |
nfsd4: fix encoding of out-of-space replies
If nfsd4_check_resp_size() returns an error then we should really be
truncating the reply here, otherwise we may leave extra garbage at the
end of the rpc reply.
Also add a warning to catch any cases where our reply-size estimates may
be wrong in the case of a non-idempotent operation.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nfsd/nfs4proc.c | 13 | ||||
| -rw-r--r-- | fs/nfsd/nfs4xdr.c | 17 | ||||
| -rw-r--r-- | fs/nfsd/xdr4.h | 2 |
3 files changed, 27 insertions, 5 deletions
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 747d6a87a47d..bf8cddfdd3be 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1171,9 +1171,7 @@ struct nfsd4_operation { static struct nfsd4_operation nfsd4_ops[]; -#ifdef NFSD_DEBUG static const char *nfsd4_op_name(unsigned opnum); -#endif /* * Enforce NFSv4.1 COMPOUND ordering rules: @@ -1859,14 +1857,21 @@ static struct nfsd4_operation nfsd4_ops[] = { }, }; -#ifdef NFSD_DEBUG +void warn_on_nonidempotent_op(struct nfsd4_op *op) +{ + if (OPDESC(op)->op_flags & OP_MODIFIES_SOMETHING) { + pr_err("unable to encode reply to nonidempotent op %d (%s)\n", + op->opnum, nfsd4_op_name(op->opnum)); + WARN_ON_ONCE(1); + } +} + static const char *nfsd4_op_name(unsigned opnum) { if (opnum < ARRAY_SIZE(nfsd4_ops)) return nfsd4_ops[opnum].op_name; return "unknown_operation"; } -#endif #define nfsd4_voidres nfsd4_voidargs struct nfsd4_voidargs { int dummy; }; diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 187925065d16..24ba652008db 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3637,6 +3637,7 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) { struct nfs4_stateowner *so = resp->cstate.replay_owner; __be32 *statp; + nfsd4_enc encoder; __be32 *p; RESERVE_SPACE(8); @@ -3648,10 +3649,24 @@ nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op) goto status; BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) || !nfsd4_enc_ops[op->opnum]); - op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u); + encoder = nfsd4_enc_ops[op->opnum]; + op->status = encoder(resp, op->status, &op->u); /* nfsd4_check_resp_size guarantees enough room for error status */ if (!op->status) op->status = nfsd4_check_resp_size(resp, 0); + if (op->status == nfserr_resource || + op->status == nfserr_rep_too_big || + op->status == nfserr_rep_too_big_to_cache) { + /* + * The operation may have already been encoded or + * partially encoded. No op returns anything additional + * in the case of one of these three errors, so we can + * just truncate back to after the status. But it's a + * bug if we had to do this on a non-idempotent op: + */ + warn_on_nonidempotent_op(op); + resp->xdr.p = statp + 1; + } if (so) { so->so_replay.rp_status = op->status; so->so_replay.rp_buflen = (char *)resp->xdr.p diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index f62a055bf63c..15ca47797a82 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -536,6 +536,8 @@ static inline bool nfsd4_last_compound_op(struct svc_rqst *rqstp) return argp->opcnt == resp->opcnt; } +void warn_on_nonidempotent_op(struct nfsd4_op *op); + #define NFS4_SVC_XDRSIZE sizeof(struct nfsd4_compoundargs) static inline void |