From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: Re: [PATCH v2] infiniband: remove WARN that is not kernel bug Date: Mon, 21 Nov 2016 14:14:08 +0200 Message-ID: <20161121121408.GC4158@leon.nu> References: <1479723531-17940-1-git-send-email-dvyukov@google.com> <20161121114417.GA4158@leon.nu> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XStn23h1fwudRqtG" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dmitry Vyukov Cc: syzkaller , Jason Gunthorpe , Valdis.Kletnieks-PjAqaU27lzQ@public.gmane.org, dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, sean.hefty-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, Hal Rosenstock , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, LKML List-Id: linux-rdma@vger.kernel.org --XStn23h1fwudRqtG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Nov 21, 2016 at 12:48:35PM +0100, Dmitry Vyukov wrote: > On Mon, Nov 21, 2016 at 12:44 PM, Leon Romanovsky wrote: > > On Mon, Nov 21, 2016 at 11:30:21AM +0100, Dmitry Vyukov wrote: > >> On Mon, Nov 21, 2016 at 11:25 AM, Miroslav Benes wrote: > >> > On Mon, 21 Nov 2016, Dmitry Vyukov wrote: > >> > > >> >> WARNINGs mean kernel bugs. > >> >> The one in ucma_write() points to user programming error > >> >> or a malicious attempt. This is not a kernel bug, remove it. > >> >> > >> >> BUG/WARNs that are not kernel bugs hinder automated testing effots. > >> >> > >> >> Signed-off-by: Dmitry Vyukov > >> >> Cc: Doug Ledford > >> >> Cc: Sean Hefty > >> >> Cc: Hal Rosenstock > >> >> Cc: Leon Romanovsky > >> >> Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > >> >> Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > >> >> Cc: syzkaller-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org > >> >> > >> >> --- > >> >> Changes since v1: > >> >> - added printk_once > >> >> --- > >> >> drivers/infiniband/core/ucma.c | 5 ++++- > >> >> 1 file changed, 4 insertions(+), 1 deletion(-) > >> >> > >> >> diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c > >> >> index 9520154..405d0ce 100644 > >> >> --- a/drivers/infiniband/core/ucma.c > >> >> +++ b/drivers/infiniband/core/ucma.c > >> >> @@ -1584,8 +1584,11 @@ static ssize_t ucma_write(struct file *filp, const char __user *buf, > >> >> struct rdma_ucm_cmd_hdr hdr; > >> >> ssize_t ret; > >> >> > >> >> - if (WARN_ON_ONCE(!ib_safe_file_access(filp))) > >> >> + if (!ib_safe_file_access(filp)) { > >> >> + printk_once("ucma_write: process %d (%s) tried to do something hinky\n", > >> >> + task_tgid_vnr(current), current->comm); > >> >> return -EACCES; > >> >> + } > >> >> > >> >> if (len < sizeof(hdr)) > >> >> return -EINVAL; > >> > > >> > FWIW, WARN_ON_ONCE came with commit e6bd18f57aad ("IB/security: Restrict > >> > use of the write() interface"). Would it make sense to change the other > >> > places as well? > >> > >> > >> I guess so. > >> Can I ask somebody of infiniband maintainers to take care of this? > > > > Please see below, > > Hope it helps. > > In ib_ucm_write function there is a wrong prefix: > > + pr_err_once("ucm_write: process %d (%s) tried to do something hinky\n", I did it intentionally to have the same errors for all flows. > > Otherwise looks good. Thanks. --XStn23h1fwudRqtG Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJYMuUQAAoJEORje4g2clin6FcP/3JE4dxipnr2Ifbxf1dK8b16 J2m3GP1PjTF76r2jHWYwRUCpjPR/aNZQYvHa895E2x+oXR335BWQroHZ1E8EH/QC ux4RmKFrOm4fUNbjkrHT6z482BlbnnkgRoBAhrCvralAObt81yVens1zOCdBLVEv NHQcPeJfxSp3aZXr2VS9r/XqYRxRmbKsWX8l1YwCRFTGNflEAQIkOZs7z3mghwNh icFDqWGpUj7eNURr5lfDRWZ2oJLWVK/f4r3pI22LlCjIeo/PhadGH7ptmJ05ysfs /kGMa6fY0rpZtlNjnl0fREO3hOhBKEwicoXte1gpOrE19XoFwIxgO+5nLG8Il1sJ 0BrVECQEEQZ97npcvj1V69ZaIZ/xOQpu4sn57dhjl6wYtngojlgEnmwpIDNTU+sx zx4O39DzaeKRdT6Wr80hgSPgnvimi3M5vVVze+CjITaWJE3wmMCmBix2b8Lq/UfE 6p32t1yY/4JEVcelWKm50CGINfYSF1PRrPY+cocYOWTW2ld7ecFTZvajRm9f7c6X q9y3r9i2JsngaBFRQo1yxYKCE3wS0Onv3kC4hlu4Is+j18K1cvbZ7ZzdT3V549X0 BywMs6funEUSmzVBmgWL0SaOEzdMLMhpguFXHRoMAjLkzYncZtRQWjw9ilQPmKql 9L2V/rK3SKGvlaDxr1Yy =Mc/T -----END PGP SIGNATURE----- --XStn23h1fwudRqtG-- -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html