[BUG] double free in dfu_free_entities()

[Lukasz Majewski]

Hi Heinrich,

> Hello Lukasz,
> 
> Jose and I have observed segmentation violations when
> dfu_free_entities() is called.
> 

Thanks for finding them.

> In our scenario we have:
> 
> dfu_alt_info=
> sf 0:0=u-boot-bin raw 0x100000 0x50000;u-boot-env raw 0x150000
> 0x200000
> 
> dfu_free_entities() is called with these entries in dfu:
> 
> u-boot-env:
>   dfu->data.sf.dev 0000000015baf420 m25p16
>   dfu->data.sf.dev->dev 0000000015888410 spi.bin at 0
> u-boot-bin:
>   dfu->data.sf.dev 0000000015baf420 m25p16
>   dfu->data.sf.dev->dev 0000000015888410 spi.bin at 0
> 
> The same device is released twice which eventually leads to the
> segmentation fault in device_chld_remove().

If I remember correctly that was fixed some time ago... Maybe something
has changed with recent patches.

Was it working before? Or is the above scenario a new one?

> 
> Program received signal SIGSEGV, Segmentation fault.
> device_chld_remove (
> dev=dev at entry=0x5555557f6750 <av_+1936>, drv=drv at entry=0x0,
> flags=flags at entry=1)
> at drivers/core/device-remove.c:55
> 55 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) {
> 
> We must ensure that dfu_free_entities() removes each device only once.
> 
> Another bug in dfu_free_entities() is that only the first list member
> is freed. free() should be called for all list members.

Yes. Correct. 

> 
> Best regards
> 
> Heinrich
> 
> 
> 




Best regards,

Lukasz Majewski

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