diff options
| author | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2025-06-12 20:26:10 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-07-10 16:04:43 +0200 |
| commit | 3419bc6a7b65cbbb91417bb9970208478e034c79 (patch) | |
| tree | 3b2e79385ac4361117b4ab35324ad53941222fc8 | |
| parent | cfbdcabab2fb5a274aba0c3426a6a71014344ad5 (diff) | |
mtk-sd: Prevent memory corruption from DMA map failure
commit f5de469990f19569627ea0dd56536ff5a13beaa3 upstream.
If msdc_prepare_data() fails to map the DMA region, the request is
not prepared for data receiving, but msdc_start_data() proceeds
the DMA with previous setting.
Since this will lead a memory corruption, we have to stop the
request operation soon after the msdc_prepare_data() fails to
prepare it.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fixes: 208489032bdd ("mmc: mediatek: Add Mediatek MMC driver")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/174972756982.3337526.6755001617701603082.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/mmc/host/mtk-sd.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index c8c4f9de30c7..7e5dda65b72f 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -783,6 +783,11 @@ static void msdc_prepare_data(struct msdc_host *host, struct mmc_data *data) } } +static bool msdc_data_prepared(struct mmc_data *data) +{ + return data->host_cookie & MSDC_PREPARE_FLAG; +} + static void msdc_unprepare_data(struct msdc_host *host, struct mmc_data *data) { if (data->host_cookie & MSDC_ASYNC_FLAG) @@ -1346,8 +1351,18 @@ static void msdc_ops_request(struct mmc_host *mmc, struct mmc_request *mrq) WARN_ON(host->mrq); host->mrq = mrq; - if (mrq->data) + if (mrq->data) { msdc_prepare_data(host, mrq->data); + if (!msdc_data_prepared(mrq->data)) { + /* + * Failed to prepare DMA area, fail fast before + * starting any commands. + */ + mrq->cmd->error = -ENOSPC; + mmc_request_done(mmc_from_priv(host), mrq); + return; + } + } /* if SBC is required, we have HW option and SW option. * if HW option is enabled, and SBC does not have "special" flags, |