Messages in this thread Patch in this message | | | From | Takashi Iwai <> | Subject | [PATCH] mmc: sdhci: Clear unused bounce buffer at DMA mmap error path | Date | Fri, 11 Jun 2021 11:03:30 +0200 |
| |
When DMA-mapping of the bounce buffer fails, the driver tries to fall back, but it leaves the allocated host->bounce_buffer although its size is zero. Later on, the driver checks the use of bounce buffer with host->bounce_buffer pointer, and it tries to use the buffer incorrectly, resulting in Oops.
This patch clears the release the unused buffer and clears the bounce_buffer pointer for addressing the problem.
Signed-off-by: Takashi Iwai <tiwai@suse.de> --- drivers/mmc/host/sdhci.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index bf238ade1602..5f467b98ca88 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -4072,9 +4072,13 @@ static void sdhci_allocate_bounce_buffer(struct sdhci_host *host) bounce_size, DMA_BIDIRECTIONAL); ret = dma_mapping_error(mmc_dev(mmc), host->bounce_addr); - if (ret) + if (ret) { + devm_kfree(mmc->parent, host->bounce_buffer); + host->bounce_buffer = NULL; /* Again fall back to max_segs == 1 */ return; + } + host->bounce_buffer_size = bounce_size; /* Lie about this since we're bouncing */ -- 2.26.2
| |