[PATCH v1] mmc: card: fixing an false identification of SANITIZE command

From: Yaniv Gardi
Date: Wed Jun 05 2013 - 07:13:45 EST


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@xxxxxxxxxxxxxx>
---
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)
--
1.7.6

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