From: Dan Carpenter <dan.carpenter@oracle.com> To: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Magnus Damm <magnus.damm@gmail.com>, Simon Horman <horms+renesas@verge.net.au>, Linux-Renesas <linux-renesas-soc@vger.kernel.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] soc: renesas: rmobile-sysc: Fix some leaks in rmobile_init_pm_domains() Date: Wed, 23 Sep 2020 13:28:28 +0300 [thread overview] Message-ID: <20200923102828.GH18329@kadam> (raw) In-Reply-To: <CAMuHMdXyM1dUPJ7ZDAk6-cEjaG_bVBfsE=bqdpf7pA0ChdRLVw@mail.gmail.com> On Wed, Sep 23, 2020 at 11:10:17AM +0200, Geert Uytterhoeven wrote: > Hi Dan, > > On Wed, Sep 23, 2020 at 10:47 AM Dan Carpenter <dan.carpenter@oracle.com> wrote: > > This code needs to call iounmap() on the error paths. > > Thanks for your patch! > > > Fixes: 2ed29e15e4b2 ("ARM: shmobile: R-Mobile: Move pm-rmobile to drivers/soc/renesas/") > > This is not the commit that introduced the issue. Duh... I don't know what I was thinking there. > > Fixes: 2173fc7cb681c38b ("ARM: shmobile: R-Mobile: Add DT support for > PM domains") > > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > > > --- a/drivers/soc/renesas/rmobile-sysc.c > > +++ b/drivers/soc/renesas/rmobile-sysc.c > > @@ -328,6 +328,7 @@ static int __init rmobile_init_pm_domains(void) > > pmd = of_get_child_by_name(np, "pm-domains"); > > if (!pmd) { > > pr_warn("%pOF lacks pm-domains node\n", np); > > + iounmap(base); > > This one I can agree with, although that case is a bug in the DTS. > > > continue; > > } > > > > @@ -341,6 +342,7 @@ static int __init rmobile_init_pm_domains(void) > > of_node_put(pmd); > > if (ret) { > > of_node_put(np); > > + iounmap(base); > > This one I cannot: in the (unlikely, only if OOM) case > rmobile_add_pm_domains() returns an error, one or more PM subdomains may > have been registered already. Hence if you call iounmap() here, the > code will try to access unmapped registers later, leading to a crash. > It's actually impossible for this rmobile_add_pm_domains() to fail on current kernels because small allocations never fail... I'll send a v2. This is for a new static checker test that I added to Smatch so I'm just sending a few of these out every day to collect feedback for now. So thanks for reviewing this, it's very helpful. regards, dan carpenter
WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com> To: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Magnus Damm <magnus.damm@gmail.com>, Simon Horman <horms+renesas@verge.net.au>, Linux-Renesas <linux-renesas-soc@vger.kernel.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] soc: renesas: rmobile-sysc: Fix some leaks in rmobile_init_pm_domains() Date: Wed, 23 Sep 2020 10:28:28 +0000 [thread overview] Message-ID: <20200923102828.GH18329@kadam> (raw) In-Reply-To: <CAMuHMdXyM1dUPJ7ZDAk6-cEjaG_bVBfsE=bqdpf7pA0ChdRLVw@mail.gmail.com> On Wed, Sep 23, 2020 at 11:10:17AM +0200, Geert Uytterhoeven wrote: > Hi Dan, > > On Wed, Sep 23, 2020 at 10:47 AM Dan Carpenter <dan.carpenter@oracle.com> wrote: > > This code needs to call iounmap() on the error paths. > > Thanks for your patch! > > > Fixes: 2ed29e15e4b2 ("ARM: shmobile: R-Mobile: Move pm-rmobile to drivers/soc/renesas/") > > This is not the commit that introduced the issue. Duh... I don't know what I was thinking there. > > Fixes: 2173fc7cb681c38b ("ARM: shmobile: R-Mobile: Add DT support for > PM domains") > > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > > > --- a/drivers/soc/renesas/rmobile-sysc.c > > +++ b/drivers/soc/renesas/rmobile-sysc.c > > @@ -328,6 +328,7 @@ static int __init rmobile_init_pm_domains(void) > > pmd = of_get_child_by_name(np, "pm-domains"); > > if (!pmd) { > > pr_warn("%pOF lacks pm-domains node\n", np); > > + iounmap(base); > > This one I can agree with, although that case is a bug in the DTS. > > > continue; > > } > > > > @@ -341,6 +342,7 @@ static int __init rmobile_init_pm_domains(void) > > of_node_put(pmd); > > if (ret) { > > of_node_put(np); > > + iounmap(base); > > This one I cannot: in the (unlikely, only if OOM) case > rmobile_add_pm_domains() returns an error, one or more PM subdomains may > have been registered already. Hence if you call iounmap() here, the > code will try to access unmapped registers later, leading to a crash. > It's actually impossible for this rmobile_add_pm_domains() to fail on current kernels because small allocations never fail... I'll send a v2. This is for a new static checker test that I added to Smatch so I'm just sending a few of these out every day to collect feedback for now. So thanks for reviewing this, it's very helpful. regards, dan carpenter
next prev parent reply other threads:[~2020-09-23 10:28 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-09-23 8:44 [PATCH] soc: renesas: rmobile-sysc: Fix some leaks in rmobile_init_pm_domains() Dan Carpenter 2020-09-23 8:44 ` Dan Carpenter 2020-09-23 9:10 ` Geert Uytterhoeven 2020-09-23 9:10 ` Geert Uytterhoeven 2020-09-23 10:28 ` Dan Carpenter [this message] 2020-09-23 10:28 ` Dan Carpenter 2020-09-23 11:31 ` [PATCH v2] " Dan Carpenter 2020-09-23 11:31 ` Dan Carpenter 2020-09-24 7:35 ` Geert Uytterhoeven 2020-09-24 7:35 ` Geert Uytterhoeven
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