Re: [PATCH v1 1/5] livepatch: Create and include UAPI headers
From: Marcos Paulo de Souza
Date: Wed Jan 10 2024 - 08:39:19 EST
On Mon, 2023-11-06 at 17:25 +0100, Lukas Hruska wrote:
> From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
>
> Define klp prefixes in include/uapi/linux/livepatch.h, and use them
> for
> replacing hard-coded values in kernel/livepatch/core.c.
>
> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> Signed-off-by: Lukas Hruska <lhruska@xxxxxxx>
Reviewed-by: Marcos Paulo de Souza <mpdesouza@xxxxxxxx>
> ---
> MAINTAINERS | 1 +
> include/uapi/linux/livepatch.h | 15 +++++++++++++++
> kernel/livepatch/core.c | 5 +++--
> 3 files changed, 19 insertions(+), 2 deletions(-)
> create mode 100644 include/uapi/linux/livepatch.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 4cc6bf79fdd8..11a2d84c1277 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -12130,6 +12130,7 @@ F: Documentation/ABI/testing/sysfs-
> kernel-livepatch
> F: Documentation/livepatch/
> F: arch/powerpc/include/asm/livepatch.h
> F: include/linux/livepatch.h
> +F: include/uapi/linux/livepatch.h
> F: kernel/livepatch/
> F: kernel/module/livepatch.c
> F: lib/livepatch/
> diff --git a/include/uapi/linux/livepatch.h
> b/include/uapi/linux/livepatch.h
> new file mode 100644
> index 000000000000..e19430918a07
> --- /dev/null
> +++ b/include/uapi/linux/livepatch.h
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +
> +/*
> + * livepatch.h - Kernel Live Patching Core
> + *
> + * Copyright (C) 2016 Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> + */
> +
> +#ifndef _UAPI_LIVEPATCH_H
> +#define _UAPI_LIVEPATCH_H
> +
> +#define KLP_RELA_PREFIX ".klp.rela."
> +#define KLP_SYM_PREFIX ".klp.sym."
> +
> +#endif /* _UAPI_LIVEPATCH_H */
> diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
> index 61328328c474..622f1916a5c8 100644
> --- a/kernel/livepatch/core.c
> +++ b/kernel/livepatch/core.c
> @@ -20,6 +20,7 @@
> #include <linux/completion.h>
> #include <linux/memory.h>
> #include <linux/rcupdate.h>
> +#include <uapi/linux/livepatch.h>
> #include <asm/cacheflush.h>
> #include "core.h"
> #include "patch.h"
> @@ -226,7 +227,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs,
> const char *strtab,
>
> /* Format: .klp.sym.sym_objname.sym_name,sympos */
> cnt = sscanf(strtab + sym->st_name,
> - ".klp.sym.%55[^.].%511[^,],%lu",
> + KLP_SYM_PREFIX "%55[^.].%511[^,],%lu",
> sym_objname, sym_name, &sympos);
> if (cnt != 3) {
> pr_err("symbol %s has an incorrectly
> formatted name\n",
> @@ -305,7 +306,7 @@ static int klp_write_section_relocs(struct module
> *pmod, Elf_Shdr *sechdrs,
> * See comment in klp_resolve_symbols() for an explanation
> * of the selected field width value.
> */
> - cnt = sscanf(shstrtab + sec->sh_name, ".klp.rela.%55[^.]",
> + cnt = sscanf(shstrtab + sec->sh_name, KLP_RELA_PREFIX
> "%55[^.]",
> sec_objname);
> if (cnt != 1) {
> pr_err("section %s has an incorrectly formatted
> name\n",