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From: Matthew Wilcox <willy@infradead.org>
To: "Burrow, Ryan - 0553 - MITLL" <Ryan.Burrow@ll.mit.edu>
Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Bug fix to ELF Loader which rejects valid ELFs
Date: Tue, 11 Aug 2020 16:05:17 +0100	[thread overview]
Message-ID: <20200811150517.GR17456@casper.infradead.org> (raw)
In-Reply-To: <c51feef9afbd4b82a3c718a072433a20@ll.mit.edu>

On Tue, Aug 11, 2020 at 02:44:08PM +0000, Burrow, Ryan - 0553 - MITLL wrote:
>  	/* Sanity check the number of program headers... */
> -	/* ...and their total size. */
> -	size = sizeof(struct elf_phdr) * elf_ex->e_phnum;
> -	if (size == 0 || size > 65536 || size > ELF_MIN_ALIGN)
> +	if (elf_ex->e_phnum == 0 || elf_ex->phnum > 65535)

umm, did you compile-test this?

assuming you meant e_phnum, it's a 16-bit quantity, so it can't be bigger
than 65535.

>  		goto out;
>  
> +	size = sizeof(struct elf_phdr) * elf_ex->e_phnum;

use array_size() here?




  reply	other threads:[~2020-08-11 15:05 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-11 14:44 [PATCH] Bug fix to ELF Loader which rejects valid ELFs Burrow, Ryan - 0553 - MITLL
2020-08-11 15:05 ` Matthew Wilcox [this message]
2020-08-11 16:39   ` Burrow, Ryan - 0553 - MITLL

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