Hi Chengfeng, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on ieee1394-linux1394/for-next] [also build test WARNING on v5.15 next-20211104] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Chengfeng-Ye/firewire-fix-potential-uaf-in-outbound_phy_packet_callback/20211104-233441 base: https://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394.git for-next config: x86_64-randconfig-r034-20211105 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 847a6807332b13f43704327c2d30103ec0347c77) 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/0day-ci/linux/commit/4374c2eea7055a681ca81f925ded194d11062af6 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Chengfeng-Ye/firewire-fix-potential-uaf-in-outbound_phy_packet_callback/20211104-233441 git checkout 4374c2eea7055a681ca81f925ded194d11062af6 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> drivers/firewire/core-cdev.c:1499:17: warning: ISO C90 forbids mixing declarations and code [-Wdeclaration-after-statement] struct client *e_client = e->client; ^ 1 warning generated. vim +1499 drivers/firewire/core-cdev.c 1477 1478 static void outbound_phy_packet_callback(struct fw_packet *packet, 1479 struct fw_card *card, int status) 1480 { 1481 struct outbound_phy_packet_event *e = 1482 container_of(packet, struct outbound_phy_packet_event, p); 1483 1484 switch (status) { 1485 /* expected: */ 1486 case ACK_COMPLETE: e->phy_packet.rcode = RCODE_COMPLETE; break; 1487 /* should never happen with PHY packets: */ 1488 case ACK_PENDING: e->phy_packet.rcode = RCODE_COMPLETE; break; 1489 case ACK_BUSY_X: 1490 case ACK_BUSY_A: 1491 case ACK_BUSY_B: e->phy_packet.rcode = RCODE_BUSY; break; 1492 case ACK_DATA_ERROR: e->phy_packet.rcode = RCODE_DATA_ERROR; break; 1493 case ACK_TYPE_ERROR: e->phy_packet.rcode = RCODE_TYPE_ERROR; break; 1494 /* stale generation; cancelled; on certain controllers: no ack */ 1495 default: e->phy_packet.rcode = status; break; 1496 } 1497 e->phy_packet.data[0] = packet->timestamp; 1498 > 1499 struct client *e_client = e->client; 1500 queue_event(e->client, &e->event, &e->phy_packet, 1501 sizeof(e->phy_packet) + e->phy_packet.length, NULL, 0); 1502 client_put(e_client); 1503 } 1504 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org