diff options
| author | Christophe JAILLET <christophe.jaillet@wanadoo.fr> | 2023-07-12 15:56:45 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2023-08-06 21:31:29 +0300 |
| commit | 0a46781c89dece85386885a407244ca26e5c1c44 (patch) | |
| tree | 5397a7589b4bec9060f210c4c2ad6b9ab70503cf /drivers/dma | |
| parent | a68b48afc050a9456ed4ed19d8755e0f925b44e6 (diff) | |
| download | linux-0a46781c89dece85386885a407244ca26e5c1c44.tar.xz | |
dmaengine: mcf-edma: Fix a potential un-allocated memory access
When 'mcf_edma' is allocated, some space is allocated for a
flexible array at the end of the struct. 'chans' item are allocated, that is
to say 'pdata->dma_channels'.
Then, this number of item is stored in 'mcf_edma->n_chans'.
A few lines later, if 'mcf_edma->n_chans' is 0, then a default value of 64
is set.
This ends to no space allocated by devm_kzalloc() because chans was 0, but
64 items are read and/or written in some not allocated memory.
Change the logic to define a default value before allocating the memory.
Fixes: e7a3ff92eaf1 ("dmaengine: fsl-edma: add ColdFire mcf5441x edma support")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/f55d914407c900828f6fad3ea5fa791a5f17b9a4.1685172449.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/mcf-edma.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/dma/mcf-edma.c b/drivers/dma/mcf-edma.c index ebd8733f72ad..9413fad08a60 100644 --- a/drivers/dma/mcf-edma.c +++ b/drivers/dma/mcf-edma.c @@ -190,7 +190,13 @@ static int mcf_edma_probe(struct platform_device *pdev) return -EINVAL; } - chans = pdata->dma_channels; + if (!pdata->dma_channels) { + dev_info(&pdev->dev, "setting default channel number to 64"); + chans = 64; + } else { + chans = pdata->dma_channels; + } + len = sizeof(*mcf_edma) + sizeof(*mcf_chan) * chans; mcf_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL); if (!mcf_edma) @@ -202,11 +208,6 @@ static int mcf_edma_probe(struct platform_device *pdev) mcf_edma->drvdata = &mcf_data; mcf_edma->big_endian = 1; - if (!mcf_edma->n_chans) { - dev_info(&pdev->dev, "setting default channel number to 64"); - mcf_edma->n_chans = 64; - } - mutex_init(&mcf_edma->fsl_edma_mutex); mcf_edma->membase = devm_platform_ioremap_resource(pdev, 0); |