From 804d8e0a6e54427268790472781e03bc243f4ee3 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 31 Mar 2023 16:31:19 -0400 Subject: [PATCH] NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL OPDESC() simply indexes into nfsd4_ops[] by the op's operation number, without range checking that value. It assumes callers are careful to avoid calling it with an out-of-bounds opnum value. nfsd4_decode_compound() is not so careful, and can invoke OPDESC() with opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end of nfsd4_ops[]. Reported-by: Jeff Layton Fixes: f4f9ef4a1b0a ("nfsd4: opdesc will be useful outside nfs4proc.c") Signed-off-by: Chuck Lever --- fs/nfsd/nfs4xdr.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 97edb32b..67bbd2d 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2476,10 +2476,12 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp) for (i = 0; i < argp->opcnt; i++) { op = &argp->ops[i]; op->replay = NULL; + op->opdesc = NULL; if (xdr_stream_decode_u32(argp->xdr, &op->opnum) < 0) return false; if (nfsd4_opnum_in_range(argp, op)) { + op->opdesc = OPDESC(op); op->status = nfsd4_dec_ops[op->opnum](argp, &op->u); if (op->status != nfs_ok) trace_nfsd_compound_decode_err(argp->rqstp, @@ -2490,7 +2492,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp) op->opnum = OP_ILLEGAL; op->status = nfserr_op_illegal; } - op->opdesc = OPDESC(op); + /* * We'll try to cache the result in the DRC if any one * op in the compound wants to be cached: -- 2.7.4