Re: [PATCH] usb: typec: ucsi: Fix null pointer dereference in ucsi_sync_control_common

[Greg KH <gregkh@linuxfoundation.org>]

On Sun, Dec 14, 2025 at 12:36:41PM -0600, Mario Limonciello (AMD) wrote:
> Add missing null check for cci parameter before dereferencing it in
> ucsi_sync_control_common(). The function can be called with cci=NULL
> from ucsi_acknowledge(), which leads to a null pointer dereference
> when accessing *cci in the condition check.
> 
> The crash occurs because the code checks if cci is not null before
> calling ucsi->ops->read_cci(ucsi, cci), but then immediately
> dereferences cci without a null check in the following condition:
> (*cci & UCSI_CCI_COMMAND_COMPLETE).
> 
> KASAN trace:
>   KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
>   RIP: 0010:ucsi_sync_control_common+0x2ae/0x4e0 [typec_ucsi]
> 
> Fixes: 667ecac55861 ("usb: typec: ucsi: return CCI and message from sync_control callback")
> Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
> ---
>  drivers/usb/typec/ucsi/ucsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Hi,

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