[android-common:android15-6.6-2025-07 1/1] kernel/trace/bpf_trace.c:3110:10: warning: default initialization of an object of type 'typeof ((attr->link_create.uprobe_multi.path))' (aka 'const unsigned long long') leaves the object uninitialized

[android-common:android15-6.6-2025-07 1/1] kernel/trace/bpf_trace.c:3110:10: warning: default initialization of an object of type 'typeof ((attr->link_create.uprobe_multi.path))' (aka 'const unsigned long long') leaves the object uninitialized

[kernel test robot]

Hi Jiri,

FYI, the error/warning still remains.

tree:   https://android.googlesource.com/kernel/common android15-6.6-2025-07
head:   37d6d309e99289fe4afaf756aa8d98a11d1642f3
commit: 89ae89f53d201143560f1e9ed4bfa62eee34f88e [1/1] bpf: Add multi uprobe link
config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20260708/202607081745.ZXvZMKw9-lkp@intel.com/config)
compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 0a2fb2a2269da0e2a3e230beb6cad39ca314db33)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260708/202607081745.ZXvZMKw9-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Fixes: 89ae89f53d20 ("bpf: Add multi uprobe link")
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202607081745.ZXvZMKw9-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> kernel/trace/bpf_trace.c:3110:10: warning: default initialization of an object of type 'typeof ((attr->link_create.uprobe_multi.path))' (aka 'const unsigned long long') leaves the object uninitialized [-Wdefault-const-init-var-unsafe]
    3110 |         upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path);
         |                 ^
   include/linux/kernel.h:62:2: note: expanded from macro 'u64_to_user_ptr'
      62 |         typecheck(u64, (x));            \
         |         ^
   include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
      11 |         typeof(x) __dummy2; \
         |                   ^
>> kernel/trace/bpf_trace.c:3111:13: warning: default initialization of an object of type 'typeof ((attr->link_create.uprobe_multi.offsets))' (aka 'const unsigned long long') leaves the object uninitialized [-Wdefault-const-init-var-unsafe]
    3111 |         uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets);
         |                    ^
   include/linux/kernel.h:62:2: note: expanded from macro 'u64_to_user_ptr'
      62 |         typecheck(u64, (x));            \
         |         ^
   include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
      11 |         typeof(x) __dummy2; \
         |                   ^
>> kernel/trace/bpf_trace.c:3117:21: warning: default initialization of an object of type 'typeof ((attr->link_create.uprobe_multi.ref_ctr_offsets))' (aka 'const unsigned long long') leaves the object uninitialized [-Wdefault-const-init-var-unsafe]
    3117 |         uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets);
         |                            ^
   include/linux/kernel.h:62:2: note: expanded from macro 'u64_to_user_ptr'
      62 |         typecheck(u64, (x));            \
         |         ^
   include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
      11 |         typeof(x) __dummy2; \
         |                   ^
   3 warnings generated.


vim +3110 kernel/trace/bpf_trace.c

  3080	
  3081	int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
  3082	{
  3083		struct bpf_uprobe_multi_link *link = NULL;
  3084		unsigned long __user *uref_ctr_offsets;
  3085		unsigned long *ref_ctr_offsets = NULL;
  3086		struct bpf_link_primer link_primer;
  3087		struct bpf_uprobe *uprobes = NULL;
  3088		unsigned long __user *uoffsets;
  3089		void __user *upath;
  3090		u32 flags, cnt, i;
  3091		struct path path;
  3092		char *name;
  3093		int err;
  3094	
  3095		/* no support for 32bit archs yet */
  3096		if (sizeof(u64) != sizeof(void *))
  3097			return -EOPNOTSUPP;
  3098	
  3099		if (prog->expected_attach_type != BPF_TRACE_UPROBE_MULTI)
  3100			return -EINVAL;
  3101	
  3102		flags = attr->link_create.uprobe_multi.flags;
  3103		if (flags & ~BPF_F_UPROBE_MULTI_RETURN)
  3104			return -EINVAL;
  3105	
  3106		/*
  3107		 * path, offsets and cnt are mandatory,
  3108		 * ref_ctr_offsets is optional
  3109		 */
> 3110		upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path);
> 3111		uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets);
  3112		cnt = attr->link_create.uprobe_multi.cnt;
  3113	
  3114		if (!upath || !uoffsets || !cnt)
  3115			return -EINVAL;
  3116	
> 3117		uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets);

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki