Re: Explanation on Uninitialized Variable bio in blk_rq_prep_clone

[Hannes Reinecke]

On 10/4/24 16:10, SurajSonawane2415 wrote:
> Explaination of how bio could be used uninitialized in this function:
>
> In the function blk_rq_prep_clone, the variable bio is declared but can remain uninitialized
> if the allocation with bio_alloc_clone fails. This can lead to undefined behavior when the
> function attempts to free bio in the error handling section using bio_put(bio).
> By initializing bio to NULL at declaration, we ensure that the cleanup code will only
> interact with bio if it has been successfully allocated.
Hate to say it, but it looks you are correct.
Care to send a patch?

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
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