Re: [PATCH] habanalabs: Fix memory corruption in debugfs

From: Oded Gabbay
Date: Mon Aug 03 2020 - 10:43:08 EST


On Mon, Aug 3, 2020 at 5:36 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> This has to be a long instead of a u32 because we write a long value.
> On 64 bit systems, this will cause memory corruption.
>
> Fixes: c216477363a3 ("habanalabs: add debugfs support")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> drivers/misc/habanalabs/common/debugfs.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/misc/habanalabs/common/debugfs.c b/drivers/misc/habanalabs/common/debugfs.c
> index 71cfe1b6fafc..ecd37b427480 100644
> --- a/drivers/misc/habanalabs/common/debugfs.c
> +++ b/drivers/misc/habanalabs/common/debugfs.c
> @@ -19,7 +19,7 @@
> static struct dentry *hl_debug_root;
>
> static int hl_debugfs_i2c_read(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
> - u8 i2c_reg, u32 *val)
> + u8 i2c_reg, long *val)
> {
> struct armcp_packet pkt;
> int rc;
> @@ -36,7 +36,7 @@ static int hl_debugfs_i2c_read(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
> pkt.i2c_reg = i2c_reg;
>
> rc = hdev->asic_funcs->send_cpu_message(hdev, (u32 *) &pkt, sizeof(pkt),
> - 0, (long *) val);
> + 0, val);
>
> if (rc)
> dev_err(hdev->dev, "Failed to read from I2C, error %d\n", rc);
> @@ -827,7 +827,7 @@ static ssize_t hl_i2c_data_read(struct file *f, char __user *buf,
> struct hl_dbg_device_entry *entry = file_inode(f)->i_private;
> struct hl_device *hdev = entry->hdev;
> char tmp_buf[32];
> - u32 val;
> + long val;
> ssize_t rc;
>
> if (*ppos)
> @@ -842,7 +842,7 @@ static ssize_t hl_i2c_data_read(struct file *f, char __user *buf,
> return rc;
> }
>
> - sprintf(tmp_buf, "0x%02x\n", val);
> + sprintf(tmp_buf, "0x%02lx\n", val);
> rc = simple_read_from_buffer(buf, count, ppos, tmp_buf,
> strlen(tmp_buf));
>
> --
> 2.27.0
>

This patch is:
Reviewed-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>

Applied to -fixes,
Thanks!
Oded