linux-kernel - [PATCH RFC] iw_cxgb4: drop check

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1547947633-10515-1-git-send-email-hofrat@osadl.org>
Date:   Sun, 20 Jan 2019 02:27:13 +0100
From:   Nicholas Mc Guire <hofrat@...dl.org>
To:     Steve Wise <swise@...lsio.com>
Cc:     Doug Ledford <dledford@...hat.com>,
        Raju Rangoju <rajur@...lsio.com>,
        Jason Gunthorpe <jgg@...pe.ca>, linux-rdma@...r.kernel.org,
        linux-kernel@...r.kernel.org, Nicholas Mc Guire <hofrat@...dl.org>
Subject: [PATCH RFC] iw_cxgb4: drop check - dead code

The kmalloc is called with  | __GFP_NOFAIL  so there is no point in
checking the return value - it either returns valid storage or it would
hang/terminate there. But it is not possible to say if the use of
__GFP_NOFAIL is really needed and the check should be removed or
vice-versa (use of __GFP_NOFAIL should be only in exceptional
cases as I understand it and alloc_srq_queue() is called in quite
a few places)
In either way it would need fixing.

Signed-off-by: Nicholas Mc Guire <hofrat@...dl.org>
Fixes: 6a0b6174d35a ("rdma/cxgb4: Add support for kernel mode SRQ's")
---

Found during code review

Patch was compile tested with: x86_64_defconfig + INFINIBAND=y,
INFINIBAND_USER_ACCESS=y, CHELSIO_T4=y, INFINIBAND_CXGB4=y
(with some unrelated sparse warnings)

Q:This also has an interesting dependency with no effect:
  Depends on:... (INFINIBAND_USER_ACCESS [=n] || !INFINIBAND_USER_ACCESS [=n])
  I assume htat INFINIBAND_USER_ACCESS=y should be required here ?

Patch is against 5.0-rc2 (localversion-next is next-20190118)

 drivers/infiniband/hw/cxgb4/qp.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/infiniband/hw/cxgb4/qp.c b/drivers/infiniband/hw/cxgb4/qp.c
index 917ce5c..c2a12ba 100644
--- a/drivers/infiniband/hw/cxgb4/qp.c
+++ b/drivers/infiniband/hw/cxgb4/qp.c
@@ -2597,8 +2597,6 @@ static int alloc_srq_queue(struct c4iw_srq *srq, struct c4iw_dev_ucontext *uctx,
 	wr_len = sizeof(*res_wr) + sizeof(*res);

 	skb = alloc_skb(wr_len, GFP_KERNEL | __GFP_NOFAIL);
-	if (!skb)
-		goto err_free_queue;
 	set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);

 	res_wr = (struct fw_ri_res_wr *)__skb_put(skb, wr_len);
-- 
2.1.4