diff mbox series

[bpf-next,v5,1/2] bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules

Message ID 14feaab32b06bd76b1689ade6f4709e246a77bbe.1676302508.git.vmalik@redhat.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series Fix attaching fentry/fexit/fmod_ret/lsm to modules | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1424 this patch: 1424
netdev/cc_maintainers warning 1 maintainers not CCed: linux-modules@vger.kernel.org
netdev/build_clang success Errors and warnings before: 152 this patch: 152
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1419 this patch: 1419
netdev/checkpatch warning WARNING: line length of 86 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-7 success Logs for llvm-toolchain
bpf/vmtest-bpf-next-VM_Test-8 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-5 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-6 success Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-2 success Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-4 success Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for test_maps on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for test_maps on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-14 fail Logs for test_progs on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-17 success Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-18 success Logs for test_progs on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-19 fail Logs for test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 fail Logs for test_progs_no_alu32 on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-22 success Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for test_progs_no_alu32 on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-24 success Logs for test_progs_no_alu32_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-27 success Logs for test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-28 success Logs for test_progs_no_alu32_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-29 success Logs for test_progs_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-32 success Logs for test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-33 success Logs for test_progs_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-34 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-37 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-38 success Logs for test_verifier on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-15 fail Logs for test_progs on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-25 success Logs for test_progs_no_alu32_parallel on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-30 success Logs for test_progs_parallel on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-35 success Logs for test_verifier on aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-21 success Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-26 success Logs for test_progs_no_alu32_parallel on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-36 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-31 success Logs for test_progs_parallel on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for test_maps on s390x with gcc

Commit Message

Viktor Malik Feb. 13, 2023, 3:59 p.m. UTC 
This resolves two problems with attachment of fentry/fexit/fmod_ret/lsm
to functions located in modules:

1. The verifier tries to find the address to attach to in kallsyms. This
   is always done by searching the entire kallsyms, not respecting the
   module in which the function is located. Such approach causes an
   incorrect attachment address to be computed if the function to attach
   to is shadowed by a function of the same name located earlier in
   kallsyms.

2. If the address to attach to is located in a module, the module
   reference is only acquired in register_fentry. If the module is
   unloaded between the place where the address is found
   (bpf_check_attach_target in the verifier) and register_fentry, it is
   possible that another module is loaded to the same address which may
   lead to potential errors.

Since the attachment must contain the BTF of the program to attach to,
we extract the module from it and search for the function address in the
correct module (resolving problem no. 1). Then, the module reference is
taken directly in bpf_check_attach_target and it is later passed to the
trampoline in bpf_trampoline_get. The reference is only released in the
corresponding bpf_trampoline_put (resolving problem no. 2).

Since bpf_trampoline_get may be called multiple times, we make sure that
the reference is only acquired and released once. If an error occurs
between bpf_check_attach_target and bpf_trampoline_get, the module
reference (stored in tgt_info) must be released.

Signed-off-by: Viktor Malik <vmalik@redhat.com>
---
 include/linux/bpf.h      |  1 +
 kernel/bpf/syscall.c     |  2 ++
 kernel/bpf/trampoline.c  | 44 +++++++++++++++-------------------------
 kernel/bpf/verifier.c    | 27 +++++++++++++++++++++---
 kernel/module/internal.h |  5 +++++
 5 files changed, 48 insertions(+), 31 deletions(-)

Comments

Jiri Olsa Feb. 13, 2023, 6:33 p.m. UTC | #1 
On Mon, Feb 13, 2023 at 04:59:58PM +0100, Viktor Malik wrote:

SNIP

> @@ -248,8 +223,6 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
>  		ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, NULL, new_addr);
>  	}
>  
> -	if (ret)
> -		bpf_trampoline_module_put(tr);
>  	return ret;
>  }
>  
> @@ -719,8 +692,11 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
>  
>  	bpf_lsm_find_cgroup_shim(prog, &bpf_func);
>  	tr = bpf_trampoline_get(key, &tgt_info);
> -	if (!tr)
> +	if (!tr) {
> +		if (tgt_info.tgt_mod)
> +			module_put(tgt_info.tgt_mod);
>  		return  -ENOMEM;
> +	}
>  
>  	mutex_lock(&tr->mutex);
>  
> @@ -800,6 +776,14 @@ struct bpf_trampoline *bpf_trampoline_get(u64 key,
>  		return NULL;
>  
>  	mutex_lock(&tr->mutex);
> +	if (tgt_info->tgt_mod) {
> +		if (tr->mod)
> +			/* we already have the module reference, release tgt_info reference */
> +			module_put(tgt_info->tgt_mod);
> +		else
> +			/* take ownership of the module reference */
> +			tr->mod = tgt_info->tgt_mod;

this seems tricky, should we take and save module reference in bpf_prog
struct and release it when the program goes out? IIUC the module for
which the program was verified for should stay as long as the program
is loaded

jirka

> +	}
>  	if (tr->func.addr)
>  		goto out;
>  
> @@ -819,6 +803,10 @@ void bpf_trampoline_put(struct bpf_trampoline *tr)
>  	mutex_lock(&trampoline_mutex);
>  	if (!refcount_dec_and_test(&tr->refcnt))
>  		goto out;
> +	if (tr->mod) {
> +		module_put(tr->mod);
> +		tr->mod = NULL;
> +	}
>  	WARN_ON_ONCE(mutex_is_locked(&tr->mutex));
>  
>  	for (i = 0; i < BPF_TRAMP_MAX; i++)

SNIP
Viktor Malik Feb. 14, 2023, 9:57 a.m. UTC | #2 
On 2/13/23 19:33, Jiri Olsa wrote:
> On Mon, Feb 13, 2023 at 04:59:58PM +0100, Viktor Malik wrote:
> 
> SNIP
> 
>> @@ -248,8 +223,6 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
>>   		ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, NULL, new_addr);
>>   	}
>>   
>> -	if (ret)
>> -		bpf_trampoline_module_put(tr);
>>   	return ret;
>>   }
>>   
>> @@ -719,8 +692,11 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
>>   
>>   	bpf_lsm_find_cgroup_shim(prog, &bpf_func);
>>   	tr = bpf_trampoline_get(key, &tgt_info);
>> -	if (!tr)
>> +	if (!tr) {
>> +		if (tgt_info.tgt_mod)
>> +			module_put(tgt_info.tgt_mod);
>>   		return  -ENOMEM;
>> +	}
>>   
>>   	mutex_lock(&tr->mutex);
>>   
>> @@ -800,6 +776,14 @@ struct bpf_trampoline *bpf_trampoline_get(u64 key,
>>   		return NULL;
>>   
>>   	mutex_lock(&tr->mutex);
>> +	if (tgt_info->tgt_mod) {
>> +		if (tr->mod)
>> +			/* we already have the module reference, release tgt_info reference */
>> +			module_put(tgt_info->tgt_mod);
>> +		else
>> +			/* take ownership of the module reference */
>> +			tr->mod = tgt_info->tgt_mod;
> 
> this seems tricky, should we take and save module reference in bpf_prog
> struct and release it when the program goes out? IIUC the module for
> which the program was verified for should stay as long as the program
> is loaded

You're right, it makes more sense that the module is associated with the
program, not with the trampoline. So we just save the mod reference into
prog->aux (in bpf_check_attach_target) and release it on bpf_prog_put,
just before the program is freed.

Does that make sense? Anything else to be aware of comes to mind?

Thanks!

Viktor

> 
> jirka
> 
>> +	}
>>   	if (tr->func.addr)
>>   		goto out;
>>   
>> @@ -819,6 +803,10 @@ void bpf_trampoline_put(struct bpf_trampoline *tr)
>>   	mutex_lock(&trampoline_mutex);
>>   	if (!refcount_dec_and_test(&tr->refcnt))
>>   		goto out;
>> +	if (tr->mod) {
>> +		module_put(tr->mod);
>> +		tr->mod = NULL;
>> +	}
>>   	WARN_ON_ONCE(mutex_is_locked(&tr->mutex));
>>   
>>   	for (i = 0; i < BPF_TRAMP_MAX; i++)
> 
> SNIP
>
kernel test robot Feb. 16, 2023, 4:49 a.m. UTC | #3 
Hi Viktor,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/intel-lab-lkp/linux/commits/Viktor-Malik/bpf-Fix-attaching-fentry-fexit-fmod_ret-lsm-to-modules/20230214-012627
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/14feaab32b06bd76b1689ade6f4709e246a77bbe.1676302508.git.vmalik%40redhat.com
patch subject: [PATCH bpf-next v5 1/2] bpf: Fix attaching fentry/fexit/fmod_ret/lsm to modules
config: arm-randconfig-r005-20230213 (https://download.01.org/0day-ci/archive/20230216/202302161237.VATmhmIP-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/ae726649987118f58eb95cd056acd6a5f0619a0f
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Viktor-Malik/bpf-Fix-attaching-fentry-fexit-fmod_ret-lsm-to-modules/20230214-012627
        git checkout ae726649987118f58eb95cd056acd6a5f0619a0f
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash kernel/bpf/ kernel/module/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302161237.VATmhmIP-lkp@intel.com/

All errors (new ones prefixed by >>):

   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) ||       \
         |                                                      ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/rculist.h:391:20: note: in expansion of macro 'list_entry_rcu'
     391 |              pos = list_entry_rcu((head)->next, typeof(*pos), member);  \
         |                    ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:299:27: error: expression in static assertion is not an integer
     299 | #define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
         |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/rculist.h:391:20: note: in expansion of macro 'list_entry_rcu'
     391 |              pos = list_entry_rcu((head)->next, typeof(*pos), member);  \
         |                    ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   In file included from include/uapi/linux/posix_types.h:5,
                    from include/uapi/linux/types.h:14,
                    from include/linux/types.h:6,
                    from include/uapi/linux/btf.h:6,
                    from kernel/bpf/verifier.c:6:
>> include/linux/stddef.h:16:33: error: invalid use of undefined type 'struct module'
      16 | #define offsetof(TYPE, MEMBER)  __builtin_offsetof(TYPE, MEMBER)
         |                                 ^~~~~~~~~~~~~~~~~~
   include/linux/container_of.h:23:28: note: in expansion of macro 'offsetof'
      23 |         ((type *)(__mptr - offsetof(type, member))); })
         |                            ^~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/rculist.h:391:20: note: in expansion of macro 'list_entry_rcu'
     391 |              pos = list_entry_rcu((head)->next, typeof(*pos), member);  \
         |                    ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   In file included from include/linux/pid.h:5,
                    from include/linux/sched.h:14,
                    from include/linux/sched/mm.h:7,
                    from include/linux/xarray.h:19,
                    from include/linux/radix-tree.h:21,
                    from include/linux/idr.h:15,
                    from include/linux/kernfs.h:12,
                    from include/linux/sysfs.h:16,
                    from include/linux/kobject.h:20,
                    from include/linux/module.h:21,
                    from include/linux/bpf.h:20:
>> include/linux/rculist.h:392:21: error: invalid use of undefined type 'struct module'
     392 |                 &pos->member != (head);                                 \
         |                     ^~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/container_of.h:19:33: note: in definition of macro 'container_of'
      19 |         void *__mptr = (void *)(ptr);                                   \
         |                                 ^~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |                            ^~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/container_of.h:19:33: note: in definition of macro 'container_of'
      19 |         void *__mptr = (void *)(ptr);                                   \
         |                                 ^~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |                            ^~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/container_of.h:19:33: note: in definition of macro 'container_of'
      19 |         void *__mptr = (void *)(ptr);                                   \
         |                                 ^~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |                            ^~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/container_of.h:19:33: note: in definition of macro 'container_of'
      19 |         void *__mptr = (void *)(ptr);                                   \
--
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/asm-generic/rwonce.h:44:43: note: in expansion of macro '__unqual_scalar_typeof'
      44 | #define __READ_ONCE(x)  (*(const volatile __unqual_scalar_typeof(x) *)&(x))
         |                                           ^~~~~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:50:9: note: in expansion of macro '__READ_ONCE'
      50 |         __READ_ONCE(x);                                                 \
         |         ^~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/asm-generic/rwonce.h:50:9: note: in expansion of macro '__READ_ONCE'
      50 |         __READ_ONCE(x);                                                 \
         |         ^~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/container_of.h:20:54: error: invalid use of undefined type 'struct module'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                                                      ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:20:23: note: in expansion of macro '__same_type'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:21:23: note: in expansion of macro '__same_type'
      21 |                       __same_type(*(ptr), void),                        \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |                            ^~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                                         ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/container_of.h:20:9: note: in expansion of macro 'static_assert'
      20 |         static_assert(__same_type(*(ptr), ((type *)0)->member) ||       \
         |         ^~~~~~~~~~~~~
   include/linux/container_of.h:21:23: note: in expansion of macro '__same_type'
      21 |                       __same_type(*(ptr), void),                        \
         |                       ^~~~~~~~~~~
   include/linux/rculist.h:307:9: note: in expansion of macro 'container_of'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |         ^~~~~~~~~~~~
   include/linux/compiler_types.h:346:9: note: in expansion of macro '__compiletime_assert'
     346 |         __compiletime_assert(condition, msg, prefix, suffix)
         |         ^~~~~~~~~~~~~~~~~~~~
   include/linux/compiler_types.h:358:9: note: in expansion of macro '_compiletime_assert'
     358 |         _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
         |         ^~~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:9: note: in expansion of macro 'compiletime_assert'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |         ^~~~~~~~~~~~~~~~~~
   include/asm-generic/rwonce.h:36:28: note: in expansion of macro '__native_word'
      36 |         compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long),  \
         |                            ^~~~~~~~~~~~~
   include/asm-generic/rwonce.h:49:9: note: in expansion of macro 'compiletime_assert_rwonce_type'
      49 |         compiletime_assert_rwonce_type(x);                              \
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:307:22: note: in expansion of macro 'READ_ONCE'
     307 |         container_of(READ_ONCE(ptr), type, member)
         |                      ^~~~~~~~~
   include/linux/rculist.h:393:23: note: in expansion of macro 'list_entry_rcu'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
         |                       ^~~~~~~~~~~~~~
   kernel/bpf/../module/internal.h:212:9: note: in expansion of macro 'list_for_each_entry_rcu'
     212 |         list_for_each_entry_rcu(mod, &modules, list,
         |         ^~~~~~~~~~~~~~~~~~~~~~~
   include/linux/rculist.h:393:41: error: invalid use of undefined type 'struct module'
     393 |                 pos = list_entry_rcu(pos->member.next, typeof(*pos), member))
..


vim +20 include/linux/container_of.h

d2a8ebbf8192b8 Andy Shevchenko  2021-11-08   9  
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  10  /**
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  11   * container_of - cast a member of a structure out to the containing structure
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  12   * @ptr:	the pointer to the member.
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  13   * @type:	the type of the container struct this is embedded in.
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  14   * @member:	the name of the member within the struct.
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  15   *
7376e561fd2e01 Sakari Ailus     2022-10-24  16   * WARNING: any const qualifier of @ptr is lost.
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  17   */
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  18  #define container_of(ptr, type, member) ({				\
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  19  	void *__mptr = (void *)(ptr);					\
e1edc277e6f6df Rasmus Villemoes 2021-11-08 @20  	static_assert(__same_type(*(ptr), ((type *)0)->member) ||	\
e1edc277e6f6df Rasmus Villemoes 2021-11-08  21  		      __same_type(*(ptr), void),			\
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  22  		      "pointer type mismatch in container_of()");	\
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  23  	((type *)(__mptr - offsetof(type, member))); })
d2a8ebbf8192b8 Andy Shevchenko  2021-11-08  24
diff mbox series

Patch

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 4385418118f6..8619bac13721 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1058,6 +1058,7 @@  struct bpf_trampoline {
 struct bpf_attach_target_info {
 	struct btf_func_model fmodel;
 	long tgt_addr;
+	struct module *tgt_mod;
 	const char *tgt_name;
 	const struct btf_type *tgt_type;
 };
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index cda8d00f3762..7072217ccffc 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3087,6 +3087,8 @@  static int bpf_tracing_prog_attach(struct bpf_prog *prog,
 
 		tr = bpf_trampoline_get(key, &tgt_info);
 		if (!tr) {
+			if (tgt_info.tgt_mod)
+				module_put(tgt_info.tgt_mod);
 			err = -ENOMEM;
 			goto out_unlock;
 		}
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index d0ed7d6f5eec..e33c051592f0 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -172,26 +172,6 @@  static struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
 	return tr;
 }
 
-static int bpf_trampoline_module_get(struct bpf_trampoline *tr)
-{
-	struct module *mod;
-	int err = 0;
-
-	preempt_disable();
-	mod = __module_text_address((unsigned long) tr->func.addr);
-	if (mod && !try_module_get(mod))
-		err = -ENOENT;
-	preempt_enable();
-	tr->mod = mod;
-	return err;
-}
-
-static void bpf_trampoline_module_put(struct bpf_trampoline *tr)
-{
-	module_put(tr->mod);
-	tr->mod = NULL;
-}
-
 static int unregister_fentry(struct bpf_trampoline *tr, void *old_addr)
 {
 	void *ip = tr->func.addr;
@@ -202,8 +182,6 @@  static int unregister_fentry(struct bpf_trampoline *tr, void *old_addr)
 	else
 		ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, old_addr, NULL);
 
-	if (!ret)
-		bpf_trampoline_module_put(tr);
 	return ret;
 }
 
@@ -238,9 +216,6 @@  static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
 		tr->func.ftrace_managed = true;
 	}
 
-	if (bpf_trampoline_module_get(tr))
-		return -ENOENT;
-
 	if (tr->func.ftrace_managed) {
 		ftrace_set_filter_ip(tr->fops, (unsigned long)ip, 0, 1);
 		ret = register_ftrace_direct_multi(tr->fops, (long)new_addr);
@@ -248,8 +223,6 @@  static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
 		ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, NULL, new_addr);
 	}
 
-	if (ret)
-		bpf_trampoline_module_put(tr);
 	return ret;
 }
 
@@ -719,8 +692,11 @@  int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
 
 	bpf_lsm_find_cgroup_shim(prog, &bpf_func);
 	tr = bpf_trampoline_get(key, &tgt_info);
-	if (!tr)
+	if (!tr) {
+		if (tgt_info.tgt_mod)
+			module_put(tgt_info.tgt_mod);
 		return  -ENOMEM;
+	}
 
 	mutex_lock(&tr->mutex);
 
@@ -800,6 +776,14 @@  struct bpf_trampoline *bpf_trampoline_get(u64 key,
 		return NULL;
 
 	mutex_lock(&tr->mutex);
+	if (tgt_info->tgt_mod) {
+		if (tr->mod)
+			/* we already have the module reference, release tgt_info reference */
+			module_put(tgt_info->tgt_mod);
+		else
+			/* take ownership of the module reference */
+			tr->mod = tgt_info->tgt_mod;
+	}
 	if (tr->func.addr)
 		goto out;
 
@@ -819,6 +803,10 @@  void bpf_trampoline_put(struct bpf_trampoline *tr)
 	mutex_lock(&trampoline_mutex);
 	if (!refcount_dec_and_test(&tr->refcnt))
 		goto out;
+	if (tr->mod) {
+		module_put(tr->mod);
+		tr->mod = NULL;
+	}
 	WARN_ON_ONCE(mutex_is_locked(&tr->mutex));
 
 	for (i = 0; i < BPF_TRAMP_MAX; i++)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 388245e8826e..ae7ba40eb535 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -24,6 +24,7 @@ 
 #include <linux/bpf_lsm.h>
 #include <linux/btf_ids.h>
 #include <linux/poison.h>
+#include "../module/internal.h"
 
 #include "disasm.h"
 
@@ -16868,6 +16869,7 @@  int bpf_check_attach_target(struct bpf_verifier_log *log,
 	const char *tname;
 	struct btf *btf;
 	long addr = 0;
+	struct module *mod = NULL;
 
 	if (!btf_id) {
 		bpf_log(log, "Tracing programs must provide btf_id\n");
@@ -17041,7 +17043,17 @@  int bpf_check_attach_target(struct bpf_verifier_log *log,
 			else
 				addr = (long) tgt_prog->aux->func[subprog]->bpf_func;
 		} else {
-			addr = kallsyms_lookup_name(tname);
+			if (btf_is_module(btf)) {
+				preempt_disable();
+				mod = btf_try_get_module(btf);
+				if (mod)
+					addr = find_kallsyms_symbol_value(mod, tname);
+				else
+					addr = 0;
+				preempt_enable();
+			} else {
+				addr = kallsyms_lookup_name(tname);
+			}
 			if (!addr) {
 				bpf_log(log,
 					"The address of function %s cannot be found\n",
@@ -17103,6 +17115,7 @@  int bpf_check_attach_target(struct bpf_verifier_log *log,
 		break;
 	}
 	tgt_info->tgt_addr = addr;
+	tgt_info->tgt_mod = mod;
 	tgt_info->tgt_name = tname;
 	tgt_info->tgt_type = t;
 	return 0;
@@ -17201,17 +17214,25 @@  static int check_attach_btf_id(struct bpf_verifier_env *env)
 
 	if (prog->type == BPF_PROG_TYPE_LSM) {
 		ret = bpf_lsm_verify_prog(&env->log, prog);
-		if (ret < 0)
+		if (ret < 0) {
+			if (tgt_info.tgt_mod)
+				module_put(tgt_info.tgt_mod);
 			return ret;
+		}
 	} else if (prog->type == BPF_PROG_TYPE_TRACING &&
 		   btf_id_set_contains(&btf_id_deny, btf_id)) {
+		if (tgt_info.tgt_mod)
+			module_put(tgt_info.tgt_mod);
 		return -EINVAL;
 	}
 
 	key = bpf_trampoline_compute_key(tgt_prog, prog->aux->attach_btf, btf_id);
 	tr = bpf_trampoline_get(key, &tgt_info);
-	if (!tr)
+	if (!tr) {
+		if (tgt_info.tgt_mod)
+			module_put(tgt_info.tgt_mod);
 		return -ENOMEM;
+	}
 
 	prog->aux->dst_trampoline = tr;
 	return 0;
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 2e2bf236f558..5cb103a46018 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -256,6 +256,11 @@  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