@@ -579,15 +579,14 @@ config IKCONFIG_PROC
This option enables access to the kernel configuration file
through /proc/config.gz.
-config IKHEADERS_PROC
- tristate "Enable kernel header artifacts through /proc/kheaders.tar.xz"
- depends on PROC_FS
- help
- This option enables access to the kernel header and other artifacts that
- are generated during the build process. These can be used to build eBPF
- tracing programs, or similar programs. If you build the headers as a
- module, a module called kheaders.ko is built which can be loaded on-demand
- to get access to the headers.
+config IKHEADERS
+ tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"
+ depends on SYSFS
+ help
+ This option enables access to the in-kernel headers that are generated during
+ the build process. These can be used to build eBPF tracing programs,
+ or similar programs. If you build the headers as a module, a module called
+ kheaders.ko is built which can be loaded on-demand to get access to headers.
config LOG_BUF_SHIFT
int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
@@ -71,7 +71,7 @@ obj-$(CONFIG_UTS_NS) += utsname.o
obj-$(CONFIG_USER_NS) += user_namespace.o
obj-$(CONFIG_PID_NS) += pid_namespace.o
obj-$(CONFIG_IKCONFIG) += configs.o
-obj-$(CONFIG_IKHEADERS_PROC) += kheaders.o
+obj-$(CONFIG_IKHEADERS) += kheaders.o
obj-$(CONFIG_SMP) += stop_machine.o
obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
@@ -127,7 +127,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE
$(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz
quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz
-cmd_genikh = $(CONFIG_SHELL) $(srctree)/kernel/gen_ikh_data.sh $@
+cmd_genikh = $(CONFIG_SHELL) $(srctree)/kernel/gen_kheaders.sh $@
$(obj)/kheaders_data.tar.xz: FORCE
$(call cmd,genikh)
similarity index 98%
rename from kernel/gen_ikh_data.sh
rename to kernel/gen_kheaders.sh
@@ -2,7 +2,7 @@
# SPDX-License-Identifier: GPL-2.0
# This script generates an archive consisting of kernel headers
-# for CONFIG_IKHEADERS_PROC.
+# for CONFIG_IKHEADERS.
set -e
spath="$(dirname "$(readlink -f "$0")")"
kroot="$spath/.."
@@ -8,9 +8,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/proc_fs.h>
+#include <linux/kobject.h>
#include <linux/init.h>
-#include <linux/uaccess.h>
/*
* Define kernel_headers_data and kernel_headers_data_end, within which the
@@ -31,39 +30,32 @@ extern char kernel_headers_data;
extern char kernel_headers_data_end;
static ssize_t
-ikheaders_read_current(struct file *file, char __user *buf,
- size_t len, loff_t *offset)
+ikheaders_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t len)
{
- return simple_read_from_buffer(buf, len, offset,
- &kernel_headers_data,
- &kernel_headers_data_end -
- &kernel_headers_data);
+ memcpy(buf, &kernel_headers_data + off, len);
+ return len;
}
-static const struct file_operations ikheaders_file_ops = {
- .read = ikheaders_read_current,
- .llseek = default_llseek,
+static struct bin_attribute kheaders_attr __ro_after_init = {
+ .attr = {
+ .name = "kheaders.tar.xz",
+ .mode = 0444,
+ },
+ .read = &ikheaders_read,
};
static int __init ikheaders_init(void)
{
- struct proc_dir_entry *entry;
-
- /* create the current headers file */
- entry = proc_create("kheaders.tar.xz", S_IRUGO, NULL,
- &ikheaders_file_ops);
- if (!entry)
- return -ENOMEM;
-
- proc_set_size(entry,
- &kernel_headers_data_end -
- &kernel_headers_data);
- return 0;
+ kheaders_attr.size = (&kernel_headers_data_end -
+ &kernel_headers_data);
+ return sysfs_create_bin_file(kernel_kobj, &kheaders_attr);
}
static void __exit ikheaders_cleanup(void)
{
- remove_proc_entry("kheaders.tar.xz", NULL);
+ sysfs_remove_bin_file(kernel_kobj, &kheaders_attr);
}
module_init(ikheaders_init);
The kheaders archive consisting of the kernel headers used for compiling bpf programs is in /proc. However there is concern that moving it here will make it permanent. Let us move it to /sys/kernel as discussed [1]. [1] https://lore.kernel.org/patchwork/patch/1067310/#1265969 Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> --- This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/ v2->v3: Fixed sysfs file mode nit (Greg). v1->v2: Fixed some kconfig nits (Masami). init/Kconfig | 17 +++++---- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 27 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)