linux-kernel - Re: [PATCH v3 3/5] mtd: rawnand: brcmnand: Fix crash during the panic

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

Date:   Wed, 5 Jul 2023 09:09:30 +0200
From:   Miquel Raynal <miquel.raynal@...tlin.com>
To:     William Zhang <william.zhang@...adcom.com>
Cc:     Broadcom Kernel List <bcm-kernel-feedback-list@...adcom.com>,
        Linux MTD List <linux-mtd@...ts.infradead.org>,
        f.fainelli@...il.com, rafal@...ecki.pl, kursad.oney@...adcom.com,
        joel.peshkin@...adcom.com, computersforpeace@...il.com,
        anand.gore@...adcom.com, dregan@...l.com, kamal.dasu@...adcom.com,
        tomer.yacoby@...adcom.com, dan.beygelman@...adcom.com,
        Florian Fainelli <florian.fainelli@...adcom.com>,
        linux-kernel@...r.kernel.org,
        Vignesh Raghavendra <vigneshr@...com>,
        Richard Weinberger <richard@....at>,
        Kamal Dasu <kdasu.kdev@...il.com>
Subject: Re: [PATCH v3 3/5] mtd: rawnand: brcmnand: Fix crash during the
 panic_write

Hi William,

william.zhang@...adcom.com wrote on Tue, 4 Jul 2023 17:40:03 -0700:

> Hi Miquel,
> 
> On 07/04/2023 08:26 AM, Miquel Raynal wrote:
> > Hi William,
> > 
> > william.zhang@...adcom.com wrote on Tue, 27 Jun 2023 12:37:36 -0700:
> >   
> >> During the panic write path to execute another nand command, if
> >> there is a pending command, we should wait for the command instead of
> >> calling BUG_ON so we don't crash while crashing.
> >>
> >> Fixes: 27c5b17cd1b1 ("mtd: nand: add NAND driver "library" for Broadcom STB NAND controller")  
> > 
> > The Fixes tag looks wrong.
> >   
> The brcmnand_send_cmd function and BUG_ON line were added by this commit and the function didn't changed much since then. Not sure why you think it is wrong?

Ok, the title of that commit let me think it was moving code rather
than adding it. Alright.

> >> Signed-off-by: William Zhang <william.zhang@...adcom.com>
> >> Reviewed-by: Florian Fainelli <florian.fainelli@...adcom.com>
> >> Reviewed-by: Kursad Oney <kursad.oney@...adcom.com>
> >> Reviewed-by: Kamal Dasu <kamal.dasu@...adcom.com>
> >> ---
> >>
> >> Changes in v3: None
> >> Changes in v2: None
> >>
> >>   drivers/mtd/nand/raw/brcmnand/brcmnand.c | 12 +++++++++++-
> >>   1 file changed, 11 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> >> index 37c2c7cfa00e..ea03104692bf 100644
> >> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> >> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> >> @@ -1608,7 +1608,17 @@ static void brcmnand_send_cmd(struct brcmnand_host *host, int cmd)  
> >>   >>   	dev_dbg(ctrl->dev, "send native cmd %d addr 0x%llx\n", cmd, cmd_addr);
> >>   >> -	BUG_ON(ctrl->cmd_pending != 0);  
> >> +	/*
> >> +	 * If we came here through _panic_write and there is a pending
> >> +	 * command, try to wait for it. If it times out, rather than
> >> +	 * hitting BUG_ON, just return so we don't crash while crashing.
> >> +	 */
> >> +	if (oops_in_progress) {
> >> +		if (ctrl->cmd_pending &&
> >> +			bcmnand_ctrl_poll_status(ctrl, NAND_CTRL_RDY, NAND_CTRL_RDY, 0))
> >> +			return;
> >> +	} else
> >> +		BUG_ON(ctrl->cmd_pending != 0);
> >>   	ctrl->cmd_pending = cmd;  
> >>   >>   	ret = bcmnand_ctrl_poll_status(ctrl, NAND_CTRL_RDY, NAND_CTRL_RDY, 0);  
> > 
> > 
> > Thanks,
> > Miquèl
> >   


Thanks,
Miquèl