[File] Uninitialized variable fix

[Christos Zoulas]

Thanks, I initialized to 0 always now.

Best,

christos

> On Feb 23, 2026, at 9:31 PM, Steve Grubb <sgrubb at redhat.com> wrote:
> 
> Hello Christos,
> 
> 
> In src/softmagic.c, we have the msetoffset function. bb can be uninitialized 
> 
> under the right conditions. At the test, if (b->fd == -1), if that is true it 
> 
> updates some offsets and does not call buffer_init. It skips both else 
> 
> statements. It continue execution at "if ((ms->flags & MAGIC_DEBUG) != 0)" 
> 
> where it might use them uninitialized if MAGIC_DEBUG was passed. But later 
> 
> after the function returns, it will call mget passing bb.fbuf and bb.flen 
> 
> which are uninitialized. They will be whatever the stack contents are.
> 
> 
> The minimal fix is to unconditionally initialize bb at the beginning of the 
> 
> function. I'm setting it to the value initialized in the normal branch. I 
> 
> think those are what gets passed to mget(). Because it was already set at the beginning  of the function, down below I deleted that one.
> 
> 
> You know the code better than I do. You may choose a different solution. 
> 
> Anyways, just wanted to pass this along. I found this with scan-build, which 
> 
> is part of clang-analyzer.
> 
> 
> Best Regards,
> 
> -Steve
> 
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