Commit bd5314f8 authored by Viktor Malik's avatar Viktor Malik Committed by Daniel Borkmann
Browse files

kallsyms, bpf: Move find_kallsyms_symbol_value out of internal header 



Moving find_kallsyms_symbol_value from kernel/module/internal.h to
include/linux/module.h. The reason is that internal.h is not prepared to
be included when CONFIG_MODULES=n. find_kallsyms_symbol_value is used by
kernel/bpf/verifier.c and including internal.h from it (without modules)
leads into a compilation error:

  In file included from ../include/linux/container_of.h:5,
                   from ../include/linux/list.h:5,
                   from ../include/linux/timer.h:5,
                   from ../include/linux/workqueue.h:9,
                   from ../include/linux/bpf.h:10,
                   from ../include/linux/bpf-cgroup.h:5,
                   from ../kernel/bpf/verifier.c:7:
  ../kernel/bpf/../module/internal.h: In function 'mod_find':
  ../include/linux/container_of.h:20:54: error: invalid use of undefined type 'struct module'
     20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
        |                                                      ^~
  [...]

This patch fixes the above error.

Fixes: 31bf1dbc ("bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules")
Reported-by: default avatarkernel test robot <lkp@intel.com>
Signed-off-by: default avatarViktor Malik <vmalik@redhat.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/oe-kbuild-all/202303161404.OrmfCy09-lkp@intel.com/
Link: https://lore.kernel.org/bpf/20230317095601.386738-1-vmalik@redhat.com
parent 94bbbdfb

include/linux/module.h

+8 −0
Original line number Diff line number Diff line
@@ -616,6 +616,8 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, 
/* Look for this name: can be of form module:name. */

unsigned long module_kallsyms_lookup_name(const char *name);



unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);



extern void __noreturn __module_put_and_kthread_exit(struct module *mod,

			long code);

#define module_put_and_kthread_exit(code) __module_put_and_kthread_exit(THIS_MODULE, code)
@@ -796,6 +798,12 @@ static inline unsigned long module_kallsyms_lookup_name(const char *name) 
	return 0;

}



static inline unsigned long find_kallsyms_symbol_value(struct module *mod,

						       const char *name)

{

	return 0;

}



static inline int register_module_notifier(struct notifier_block *nb)

{

	/* no events will happen anyway, so this can always succeed */

kernel/bpf/verifier.c

+1 −1
Original line number Diff line number Diff line
@@ -24,7 +24,7 @@ 
#include <linux/bpf_lsm.h>

#include <linux/btf_ids.h>

#include <linux/poison.h>

#include "../module/internal.h"

#include <linux/module.h>









#include "disasm.h"








































kernel/module/internal.h



+0
−6






























Original line number
Diff line number
Diff line







@@ -246,7 +246,6 @@ static inline void kmemleak_load_module(const struct module *mod,







void init_build_id(struct module *mod, const struct load_info *info);









void layout_symtab(struct module *mod, struct load_info *info);









void add_kallsyms(struct module *mod, const struct load_info *info);









unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name);



















static inline bool sect_empty(const Elf_Shdr *sect)









{








@@ -256,11 +255,6 @@ static inline bool sect_empty(const Elf_Shdr *sect)







static inline void init_build_id(struct module *mod, const struct load_info *info) { }









static inline void layout_symtab(struct module *mod, struct load_info *info) { }









static inline void add_kallsyms(struct module *mod, const struct load_info *info) { }









static inline unsigned long find_kallsyms_symbol_value(struct module *mod,









						       const char *name)









{









	return 0;









}









#endif /* CONFIG_KALLSYMS */



















#ifdef CONFIG_SYSFS