2023-03-14 16:54:35

by Wei Chen

[permalink] [raw]
Subject: [PATCH v4] i2c: xgene-slimpro: Fix out-of-bounds bug in xgene_slimpro_i2c_xfer()

The data->block[0] variable comes from user and is a number between
0-255. Without proper check, the variable may be very large to cause
an out-of-bounds when performing memcpy in slimpro_i2c_blkwr.

Fix this bug by checking the value of writelen.

Fixes: f6505fbabc42 ("i2c: add SLIMpro I2C device driver on APM X-Gene platform")
Signed-off-by: Wei Chen <[email protected]>
Cc: [email protected]
---
Changes in v2:
- Put length check inside slimpro_i2c_blkwr
Changes in v3:
- Correct the format of patch
Changes in v4:
- CC stable email address

drivers/i2c/busses/i2c-xgene-slimpro.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/busses/i2c-xgene-slimpro.c b/drivers/i2c/busses/i2c-xgene-slimpro.c
index bc9a3e7e0c96..0f7263e2276a 100644
--- a/drivers/i2c/busses/i2c-xgene-slimpro.c
+++ b/drivers/i2c/busses/i2c-xgene-slimpro.c
@@ -308,6 +308,9 @@ static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip,
u32 msg[3];
int rc;

+ if (writelen > I2C_SMBUS_BLOCK_MAX)
+ return -EINVAL;
+
memcpy(ctx->dma_buffer, data, writelen);
paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
DMA_TO_DEVICE);
--
2.25.1



2023-03-14 17:06:03

by Andi Shyti

[permalink] [raw]
Subject: Re: [PATCH v4] i2c: xgene-slimpro: Fix out-of-bounds bug in xgene_slimpro_i2c_xfer()

Hi Wei,

On Tue, Mar 14, 2023 at 04:54:21PM +0000, Wei Chen wrote:
> The data->block[0] variable comes from user and is a number between
> 0-255. Without proper check, the variable may be very large to cause
> an out-of-bounds when performing memcpy in slimpro_i2c_blkwr.
>
> Fix this bug by checking the value of writelen.
>
> Fixes: f6505fbabc42 ("i2c: add SLIMpro I2C device driver on APM X-Gene platform")
> Signed-off-by: Wei Chen <[email protected]>
> Cc: [email protected]

and...

Reviewed-by: Andi Shyti <[email protected]>

Thanks,
Andi

2023-03-16 20:16:22

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH v4] i2c: xgene-slimpro: Fix out-of-bounds bug in xgene_slimpro_i2c_xfer()

On Tue, Mar 14, 2023 at 04:54:21PM +0000, Wei Chen wrote:
> The data->block[0] variable comes from user and is a number between
> 0-255. Without proper check, the variable may be very large to cause
> an out-of-bounds when performing memcpy in slimpro_i2c_blkwr.
>
> Fix this bug by checking the value of writelen.
>
> Fixes: f6505fbabc42 ("i2c: add SLIMpro I2C device driver on APM X-Gene platform")
> Signed-off-by: Wei Chen <[email protected]>
> Cc: [email protected]

Applied to for-current, thanks!


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