[scosu-sched:topic/mmap-cap-prot-wip/v6.18 115/1130] kernel/ptrace.c:1339:37: error: passing 'void **' to parameter of type 'const void **' discards qualifiers in nested pointer types

[scosu-sched:topic/mmap-cap-prot-wip/v6.18 115/1130] kernel/ptrace.c:1339:37: error: passing 'void **' to parameter of type 'const void **' discards qualifiers in nested pointer types

[kernel test robot]

Hi Christian,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree:   https://github.com/scosu/linux-sched topic/mmap-cap-prot-wip/v6.18
head:   f69a5a9d9fee15edde28429e23a4c749a59937bd
commit: b8dd58a99f3a6b933636441f72da97e1a06c8a57 [115/1130] [CHERRY-PICK] kernel/ptrace: Modify ptrace syscall to accept capability arguments
config: um-allnoconfig (https://download.01.org/0day-ci/archive/20260521/202605211145.HiFuURcJ-lkp@intel.com/config)
compiler: clang version 23.0.0git (https://github.com/llvm/llvm-project 5bac06718f502014fade905512f1d26d578a18f3)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260521/202605211145.HiFuURcJ-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
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605211145.HiFuURcJ-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from kernel/ptrace.c:16:
   In file included from include/linux/sched/task.h:13:
   include/linux/uaccess.h:726:9: warning: 'get_user_ptr' macro redefined [-Wmacro-redefined]
     726 | #define get_user_ptr(x,y) __get_user(x,y)
         |         ^
   include/asm-generic/uaccess.h:259:9: note: previous definition is here
     259 | #define get_user_ptr(x, ptr)                                    \
         |         ^
   In file included from kernel/ptrace.c:16:
   In file included from include/linux/sched/task.h:13:
   include/linux/uaccess.h:727:9: warning: 'put_user_ptr' macro redefined [-Wmacro-redefined]
     727 | #define put_user_ptr(x,y) __put_user(x,y)
         |         ^
   include/asm-generic/uaccess.h:218:9: note: previous definition is here
     218 | #define put_user_ptr(x, ptr)                                    \
         |         ^
>> kernel/ptrace.c:1339:37: error: passing 'void **' to parameter of type 'const void **' discards qualifiers in nested pointer types [-Werror,-Wincompatible-pointer-types-discards-qualifiers]
    1339 |                 if (__get_user_ptr(kiov.iov_base, &uiov->iov_base) ||
         |                                                   ^~~~~~~~~~~~~~~
   include/asm-generic/uaccess.h:254:31: note: expanded from macro '__get_user_ptr'
     254 |         __gu_err = __get_user_ptr_fn(ptr, &__x);                \
         |                                      ^~~
   include/asm-generic/uaccess.h:286:51: note: expanded from macro '__get_user_ptr_fn'
     286 | #define __get_user_ptr_fn(u, k) __get_user_ptr_fn(u, k)
         |                                                   ^
   include/asm-generic/uaccess.h:279:47: note: passing argument to parameter 'ptr' here
     279 | __get_user_ptr_fn(const void __user * __user *ptr,
         |                                               ^
   2 warnings and 1 error generated.


vim +1339 kernel/ptrace.c

  1313	
  1314		case PTRACE_SINGLESTEP:
  1315	#ifdef PTRACE_SINGLEBLOCK
  1316		case PTRACE_SINGLEBLOCK:
  1317	#endif
  1318	#ifdef PTRACE_SYSEMU
  1319		case PTRACE_SYSEMU:
  1320		case PTRACE_SYSEMU_SINGLESTEP:
  1321	#endif
  1322		case PTRACE_SYSCALL:
  1323		case PTRACE_CONT:
  1324			return ptrace_resume(child, request, data);
  1325	
  1326		case PTRACE_KILL:
  1327			send_sig_info(SIGKILL, SEND_SIG_NOINFO, child);
  1328			return 0;
  1329	
  1330	#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
  1331		case PTRACE_GETREGSET:
  1332		case PTRACE_SETREGSET: {
  1333			struct iovec kiov;
  1334			struct iovec __user *uiov = datavp;
  1335	
  1336			if (!access_ok(uiov, sizeof(*uiov)))
  1337				return -EFAULT;
  1338	
> 1339			if (__get_user_ptr(kiov.iov_base, &uiov->iov_base) ||
  1340			    __get_user(kiov.iov_len, &uiov->iov_len))
  1341				return -EFAULT;
  1342	
  1343			ret = ptrace_regset(child, request, addr, &kiov);
  1344			if (!ret)
  1345				ret = __put_user(kiov.iov_len, &uiov->iov_len);
  1346			break;
  1347		}
  1348	
  1349		case PTRACE_GET_SYSCALL_INFO:
  1350			ret = ptrace_get_syscall_info(child, addr, datavp);
  1351			break;
  1352	
  1353		case PTRACE_SET_SYSCALL_INFO:
  1354			ret = ptrace_set_syscall_info(child, addr, datavp);
  1355			break;
  1356	#endif
  1357	
  1358		case PTRACE_SECCOMP_GET_FILTER:
  1359			ret = seccomp_get_filter(child, addr, datavp);
  1360			break;
  1361	
  1362		case PTRACE_SECCOMP_GET_METADATA:
  1363			ret = seccomp_get_metadata(child, addr, datavp);
  1364			break;
  1365	

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