From: Chris Ball <cjb@laptop.org>
To: Yaniv Gardi <ygardi@codeaurora.org>
Cc: linux-mmc@vger.kernel.org, linux-arm-msm@vger.kernel.org,
open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1] mmc: card: fixing an false identification of SANITIZE command
Date: Thu, 27 Jun 2013 11:28:32 -0400 [thread overview]
Message-ID: <874ncjpo7z.fsf@octavius.laptop.org> (raw)
In-Reply-To: <1370430804-5663-1-git-send-email-ygardi@codeaurora.org> (Yaniv Gardi's message of "Wed, 5 Jun 2013 14:13:08 +0300")
Hi Yaniv,
On Wed, Jun 05 2013, Yaniv Gardi wrote:
> Inside the routine mmc_blk_ioctl_cmd() the sanitize command is
> identified according to the value of bits 16-23 of the argument.
>
> but what happens if a different command is sent, and only by chance,
> bits 16-23 contain the value of SANITIZE command ?
> In that case a SANITIZE command will be falsely identified.
> In order to prevent such a case, the condition is expanded and
> now it also checks the opcode itself, and verifies that it is an
> MMC_SWITCH opcode.
>
> Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
> ---
> drivers/mmc/card/block.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index c900d28..9775ae7 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -542,7 +542,9 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
> goto cmd_rel_host;
> }
>
> - if (MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) {
> + if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) &&
> + (cmd.opcode == MMC_SWITCH)) {
> +
> err = ioctl_do_sanitize(card);
>
> if (err)
Thanks, pushed to mmc-next for 3.11.
- Chris.
--
Chris Ball <cjb@laptop.org> <http://printf.net/>
One Laptop Per Child
WARNING: multiple messages have this Message-ID (diff)
From: Chris Ball <cjb@laptop.org>
To: Yaniv Gardi <ygardi@codeaurora.org>
Cc: linux-mmc@vger.kernel.org, linux-arm-msm@vger.kernel.org,
linux-kernel@vger.kernel.org (open list)
Subject: Re: [PATCH v1] mmc: card: fixing an false identification of SANITIZE command
Date: Thu, 27 Jun 2013 11:28:32 -0400 [thread overview]
Message-ID: <874ncjpo7z.fsf@octavius.laptop.org> (raw)
In-Reply-To: <1370430804-5663-1-git-send-email-ygardi@codeaurora.org> (Yaniv Gardi's message of "Wed, 5 Jun 2013 14:13:08 +0300")
Hi Yaniv,
On Wed, Jun 05 2013, Yaniv Gardi wrote:
> Inside the routine mmc_blk_ioctl_cmd() the sanitize command is
> identified according to the value of bits 16-23 of the argument.
>
> but what happens if a different command is sent, and only by chance,
> bits 16-23 contain the value of SANITIZE command ?
> In that case a SANITIZE command will be falsely identified.
> In order to prevent such a case, the condition is expanded and
> now it also checks the opcode itself, and verifies that it is an
> MMC_SWITCH opcode.
>
> Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
> ---
> drivers/mmc/card/block.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index c900d28..9775ae7 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -542,7 +542,9 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
> goto cmd_rel_host;
> }
>
> - if (MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) {
> + if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) &&
> + (cmd.opcode == MMC_SWITCH)) {
> +
> err = ioctl_do_sanitize(card);
>
> if (err)
Thanks, pushed to mmc-next for 3.11.
- Chris.
--
Chris Ball <cjb@laptop.org> <http://printf.net/>
One Laptop Per Child
next prev parent reply other threads:[~2013-06-27 15:28 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-05 11:13 [PATCH v1] mmc: card: fixing an false identification of SANITIZE command Yaniv Gardi
2013-06-05 11:13 ` Yaniv Gardi
2013-06-27 15:28 ` Chris Ball [this message]
2013-06-27 15:28 ` Chris Ball
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=874ncjpo7z.fsf@octavius.laptop.org \
--to=cjb@laptop.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mmc@vger.kernel.org \
--cc=ygardi@codeaurora.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.