Re: [PATCH v2] staging: media: ipu7: fix double-free and use-after-free in error paths

[Dan Carpenter <error27@gmail.com>]

On Mon, Apr 13, 2026 at 12:15:33PM +0200, Alexandru Hossu wrote:
> In both ipu7_isys_init() and ipu7_psys_init(), pdata is allocated and
> then passed to ipu7_bus_initialize_device(), which stores it in
> adev->pdata. The ipu7_bus_release() function frees adev->pdata when the
> device's reference count drops to zero.
> 
> Two error paths incorrectly call kfree(pdata) after the device teardown
> has already freed it:
> 
> 1. When ipu7_mmu_init() fails: put_device() is called, which drops the
>    reference count to zero and triggers ipu7_bus_release() ->
>    kfree(pdata). The subsequent kfree(pdata) is a double-free.
> 
> 2. When ipu7_bus_add_device() fails: it calls auxiliary_device_uninit()
>    internally, which calls put_device() -> ipu7_bus_release() ->
>    kfree(pdata). The subsequent kfree(pdata) is again a double-free.
> 
> Note that the kfree(pdata) when ipu7_bus_initialize_device() itself
> fails is correct, because in that case auxiliary_device_init() failed
> and the release function was never set up, so pdata must be freed
> manually.
> 
> Additionally, the error code was not saved before calling put_device(),
> causing ERR_CAST() to dereference the already-freed adev pointer when
> constructing the return value. Fix this by saving the error from
> dev_err_probe() before put_device() and returning ERR_PTR() instead.
> 
> Remove the redundant kfree(pdata) calls and fix the use-after-free in
> the return values of the two affected error paths.
> 
> Fixes: b7fe4c0019b1 ("media: staging/ipu7: add Intel IPU7 PCI device driver")
> Signed-off-by: Alexandru Hossu <hossu.alexandru@gmail.com>
> ---

Both the resent patches are fine now.

Reviewed-by: Dan Carpenter <error27@gmail.com>

However, please could you resend the whole patch series as a new thread
(with the first two or whatever dropped)?

regards,
dan carpenter