tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git pending-fixes head: 6edb22d074776a37273a470ad7aa041671a1b9f3 commit: 4c559f15efcc43b996f4da528cd7f9483aaca36d [119/144] netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code config: um-allmodconfig (attached as .config) compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0 reproduce (this is a W=1 build): git checkout 4c559f15efcc43b996f4da528cd7f9483aaca36d # save the attached .config to linux build tree make W=1 ARCH=um If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): cc1: warning: arch/um/include/uapi: No such file or directory [-Wmissing-include-dirs] In file included from include/linux/kernel.h:11:0, from include/linux/list.h:9, from include/linux/module.h:12, from net/netfilter/nf_conntrack_pptp.c:26: include/asm-generic/fixmap.h: In function 'fix_to_virt': include/asm-generic/fixmap.h:32:19: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] BUILD_BUG_ON(idx >= __end_of_fixed_addresses); ^ include/linux/compiler.h:330:9: note: in definition of macro '__compiletime_assert' if (!(condition)) ^~~~~~~~~ include/linux/compiler.h:350:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:50:2: note: in expansion of macro 'BUILD_BUG_ON_MSG' BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) ^~~~~~~~~~~~~~~~ include/asm-generic/fixmap.h:32:2: note: in expansion of macro 'BUILD_BUG_ON' BUILD_BUG_ON(idx >= __end_of_fixed_addresses); ^~~~~~~~~~~~ In file included from include/linux/uaccess.h:11:0, from include/linux/sched/task.h:11, from include/linux/sched/signal.h:9, from include/linux/rcuwait.h:6, from include/linux/percpu-rwsem.h:7, from include/linux/fs.h:34, from include/linux/huge_mm.h:8, from include/linux/mm.h:679, from include/linux/bvec.h:13, from include/linux/skbuff.h:17, from net/netfilter/nf_conntrack_pptp.c:27: arch/um/include/asm/uaccess.h: In function '__access_ok': arch/um/include/asm/uaccess.h:17:29: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] (((unsigned long) (addr) >= FIXADDR_USER_START) && ^ arch/um/include/asm/uaccess.h:45:3: note: in expansion of macro '__access_ok_vsyscall' __access_ok_vsyscall(addr, size) || ^~~~~~~~~~~~~~~~~~~~ In file included from net/netfilter/nf_conntrack_pptp.c:36:0: include/linux/netfilter/nf_conntrack_pptp.h: At top level: include/linux/netfilter/nf_conntrack_pptp.h:13:8: warning: type qualifiers ignored on function return type [-Wignored-qualifiers] extern const char *const pptp_msg_name(u_int16_t msg); ^~~~~ const char *const pptp_msg_name(u_int16_t msg) ^~~~~ vim +94 net/netfilter/nf_conntrack_pptp.c 93 95 { 96 if (msg > PPTP_MSG_MAX) 97 return pptp_msg_name_array[0]; 98 99 return pptp_msg_name_array[msg]; 100 } 101 EXPORT_SYMBOL(pptp_msg_name); 102 #endif 103 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org