Re: [PATCH] module: prevent warning when finit_module a 0 sized file

From: Rusty Russell
Date: Sun Jan 06 2013 - 20:17:18 EST

Sasha Levin <sasha.levin@xxxxxxxxxx> writes:
> On 01/02/2013 07:41 PM, Rusty Russell wrote:
>> Sasha Levin <sasha.levin@xxxxxxxxxx> writes:
>>> If we try to finit_module on a file sized 0 bytes vmalloc will
>>> scream and spit out a warning.
>>> Since modules have to be bigger than 0 bytes anyways we can just
>>> check that beforehand and avoid the warning.
>> Applied, but I added the comment you somehow missed :)
> Thanks!
> I do have a somewhat related follow-up question:
> When init_module() goes through the module loading process, it will try to vmalloc()
> whatever size passed to it by the user, which may cause vmalloc() to scream and shout
> if the size passed from userspace is too big.
> Do you think that reading just the header and doing a quick elf_header_check() on
> it before trying to read the entire file would make sense here?

No. Root asked, we do. If modprobe wants to check the header, let it.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at