Return-Path: Received: from fieldses.org ([173.255.197.46]:50222 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751294AbdJXRxm (ORCPT ); Tue, 24 Oct 2017 13:53:42 -0400 Date: Tue, 24 Oct 2017 13:53:42 -0400 From: "J. Bruce Fields" To: Weston Andros Adamson Cc: "Gustavo A. R. Silva" , Jeff Layton , Trond Myklebust , Anna Schumaker , "David S. Miller" , linux-nfs list , netdev@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] net: sunrpc: svcauth_gss: use BUG_ON instead of if condition followed by BUG Message-ID: <20171024175342.GA27853@fieldses.org> References: <20171023181635.GA25334@embeddedor.com> <20171023203135.GA21106@fieldses.org> <496D700A-E9D1-4745-B5DE-24BB9231A449@monkey.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <496D700A-E9D1-4745-B5DE-24BB9231A449@monkey.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tue, Oct 24, 2017 at 01:26:49PM -0400, Weston Andros Adamson wrote: > Is there a reason to BUG() in these places? Couldn't we WARN_ON_ONCE and return an error? I think the BUG() will just kill an nfsd thread that isn't holding any interesting locks. The failures look unlikely. (Except for that read_u32... return, I wonder if we're missing a check there.) --b. > > -dros > > > On Oct 23, 2017, at 4:31 PM, J. Bruce Fields wrote: > > > > In the past we've avoided BUG_ON(X) where X might have side effects, on > > the theory that it should actually be OK just to compile out BUG_ON()s. > > Has that changed? > > > > In any case, I don't find that this improves readability; dropping. > > > > --b. > > > > On Mon, Oct 23, 2017 at 01:16:35PM -0500, Gustavo A. R. Silva wrote: > >> Use BUG_ON instead of if condition followed by BUG. > >> > >> This issue was detected with the help of Coccinelle. > >> > >> Signed-off-by: Gustavo A. R. Silva > >> --- > >> net/sunrpc/auth_gss/svcauth_gss.c | 9 +++------ > >> 1 file changed, 3 insertions(+), 6 deletions(-) > >> > >> diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c > >> index 7b1ee5a..a10ce43 100644 > >> --- a/net/sunrpc/auth_gss/svcauth_gss.c > >> +++ b/net/sunrpc/auth_gss/svcauth_gss.c > >> @@ -855,11 +855,9 @@ unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct g > >> return stat; > >> if (integ_len > buf->len) > >> return stat; > >> - if (xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)) > >> - BUG(); > >> + BUG_ON(xdr_buf_subsegment(buf, &integ_buf, 0, integ_len)); > >> /* copy out mic... */ > >> - if (read_u32_from_xdr_buf(buf, integ_len, &mic.len)) > >> - BUG(); > >> + BUG_ON(read_u32_from_xdr_buf(buf, integ_len, &mic.len)); > >> if (mic.len > RPC_MAX_AUTH_SIZE) > >> return stat; > >> mic.data = kmalloc(mic.len, GFP_KERNEL); > >> @@ -1611,8 +1609,7 @@ svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp) > >> BUG_ON(integ_len % 4); > >> *p++ = htonl(integ_len); > >> *p++ = htonl(gc->gc_seq); > >> - if (xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)) > >> - BUG(); > >> + BUG_ON(xdr_buf_subsegment(resbuf, &integ_buf, integ_offset, integ_len)); > >> if (resbuf->tail[0].iov_base == NULL) { > >> if (resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE > PAGE_SIZE) > >> goto out_err; > >> -- > >> 2.7.4 > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html