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Date:   Thu, 30 Mar 2023 15:10:03 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     Joe Lawrence <joe.lawrence@redhat.com>
Cc:     live-patching@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kbuild@vger.kernel.org, Josh Poimboeuf <jpoimboe@kernel.org>,
        Miroslav Benes <mbenes@suse.cz>,
        Petr Mladek <pmladek@suse.com>,
        Marcos Paulo de Souza <mpdesouza@suse.com>
Subject: Re: [PATCH v7 00/10] livepatch: klp-convert tool
Message-ID: <4ce29654-4e1e-4680-9c25-715823ff5e02@p183>
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Joe Lawrence wrote:
> +static int update_strtab(struct elf *elf)
> +{
>
> +	buf = malloc(new_size);
> +	if (!buf) {
> +		WARN("malloc failed");
> +		return -1;
> +	}
> +	memcpy(buf, (void *)strtab->data, orig_size);

This code is called realloc(). :-)

> +static int write_file(struct elf *elf, const char *file)
> +{
>
> +	fd = creat(file, 0664);
> +	e = elf_begin(fd, ELF_C_WRITE, NULL);

elf_end() doesn't close descriptor, so there is potentially corrupted
data. There is no unlink() call if writes fail as well.

> +void elf_close(struct elf *elf)
> +{
> +
> +	if (elf->fd > 0)
> +		close(elf->fd);

Techically, it is "fd >= 0".

> +filechk_klp_map = \
> +	echo "klp-convert-symbol-data.0.1";		\
> +	echo "*vmlinux";				\
> +	$(NM) -f posix vmlinux | cut -d\  -f1;		\
> +	sort $(MODORDER) $(MODULES_LIVEPATCH) |		\

This probably should be "LC_ALL=C sort" for speed and reproducibility (?).