include/linux/netlink.h:116:13: warning: ' TXQs for network stack (tot...' directive output truncated writing 31 bytes into a region of size between 0 and 14

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   2c40c1c6adab90ee4660caf03722b3a3ec67767b
commit: 800db2d125c2bc22c448e2386c3518e663d6db71 net: enetc: ensure we always have a minimum number of TXQs for stack
date:   9 months ago
config: alpha-allyesconfig (https://download.01.org/0day-ci/archive/20231104/202311041206.ZG6Mb1tm-lkp@xxxxxxxxx/config)
compiler: alpha-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231104/202311041206.ZG6Mb1tm-lkp@xxxxxxxxx/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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202311041206.ZG6Mb1tm-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

   In file included from include/uapi/linux/neighbour.h:6,
                    from include/linux/netdevice.h:46,
                    from drivers/net/ethernet/freescale/enetc/enetc.h:6,
                    from drivers/net/ethernet/freescale/enetc/enetc.c:4:
   In function 'enetc_setup_xdp_prog',
       inlined from 'enetc_setup_bpf' at drivers/net/ethernet/freescale/enetc/enetc.c:2733:10:
>> include/linux/netlink.h:116:13: warning: ' TXQs for network stack (tot...' directive output truncated writing 31 bytes into a region of size between 0 and 14 [-Wformat-truncation=]
     116 |         if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN,               \
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     117 |                      "%s" fmt "%s", "", ##args, "") >=                         \
         |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/netlink.h:131:9: note: in expansion of macro 'NL_SET_ERR_MSG_FMT'
     131 |         NL_SET_ERR_MSG_FMT((extack), KBUILD_MODNAME ": " fmt, ##args)
         |         ^~~~~~~~~~~~~~~~~~
   drivers/net/ethernet/freescale/enetc/enetc.c:2713:17: note: in expansion of macro 'NL_SET_ERR_MSG_FMT_MOD'
    2713 |                 NL_SET_ERR_MSG_FMT_MOD(extack,
         |                 ^~~~~~~~~~~~~~~~~~~~~~
   include/linux/netlink.h:116:13: note: directive argument in the range [0, 65535]
     116 |         if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN,               \
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     117 |                      "%s" fmt "%s", "", ##args, "") >=                         \
         |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/netlink.h:131:9: note: in expansion of macro 'NL_SET_ERR_MSG_FMT'
     131 |         NL_SET_ERR_MSG_FMT((extack), KBUILD_MODNAME ": " fmt, ##args)
         |         ^~~~~~~~~~~~~~~~~~
   drivers/net/ethernet/freescale/enetc/enetc.c:2713:17: note: in expansion of macro 'NL_SET_ERR_MSG_FMT_MOD'
    2713 |                 NL_SET_ERR_MSG_FMT_MOD(extack,
         |                 ^~~~~~~~~~~~~~~~~~~~~~
   include/linux/netlink.h:116:13: note: 'snprintf' output between 110 and 134 bytes into a destination of size 80
     116 |         if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN,               \
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     117 |                      "%s" fmt "%s", "", ##args, "") >=                         \
         |                      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/netlink.h:131:9: note: in expansion of macro 'NL_SET_ERR_MSG_FMT'
     131 |         NL_SET_ERR_MSG_FMT((extack), KBUILD_MODNAME ": " fmt, ##args)
         |         ^~~~~~~~~~~~~~~~~~
   drivers/net/ethernet/freescale/enetc/enetc.c:2713:17: note: in expansion of macro 'NL_SET_ERR_MSG_FMT_MOD'
    2713 |                 NL_SET_ERR_MSG_FMT_MOD(extack,
         |                 ^~~~~~~~~~~~~~~~~~~~~~


vim +116 include/linux/netlink.h

2d4bc93368f5a0 Johannes Berg 2017-04-12  107  
51c352bdbcd23d Edward Cree   2022-10-18  108  /* We splice fmt with %s at each end even in the snprintf so that both calls
51c352bdbcd23d Edward Cree   2022-10-18  109   * can use the same string constant, avoiding its duplication in .ro
51c352bdbcd23d Edward Cree   2022-10-18  110   */
51c352bdbcd23d Edward Cree   2022-10-18  111  #define NL_SET_ERR_MSG_FMT(extack, fmt, args...) do {			       \
51c352bdbcd23d Edward Cree   2022-10-18  112  	struct netlink_ext_ack *__extack = (extack);			       \
51c352bdbcd23d Edward Cree   2022-10-18  113  									       \
51c352bdbcd23d Edward Cree   2022-10-18  114  	if (!__extack)							       \
51c352bdbcd23d Edward Cree   2022-10-18  115  		break;							       \
51c352bdbcd23d Edward Cree   2022-10-18 @116  	if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN,	       \
51c352bdbcd23d Edward Cree   2022-10-18  117  		     "%s" fmt "%s", "", ##args, "") >=			       \
51c352bdbcd23d Edward Cree   2022-10-18  118  	    NETLINK_MAX_FMTMSG_LEN)					       \
51c352bdbcd23d Edward Cree   2022-10-18  119  		net_warn_ratelimited("%s" fmt "%s", "truncated extack: ",      \
51c352bdbcd23d Edward Cree   2022-10-18  120  				     ##args, "\n");			       \
51c352bdbcd23d Edward Cree   2022-10-18  121  									       \
51c352bdbcd23d Edward Cree   2022-10-18  122  	do_trace_netlink_extack(__extack->_msg_buf);			       \
51c352bdbcd23d Edward Cree   2022-10-18  123  									       \
51c352bdbcd23d Edward Cree   2022-10-18  124  	__extack->_msg = __extack->_msg_buf;				       \
51c352bdbcd23d Edward Cree   2022-10-18  125  } while (0)
51c352bdbcd23d Edward Cree   2022-10-18  126  

:::::: The code at line 116 was first introduced by commit
:::::: 51c352bdbcd23d7ce46b06c1e64c82754dc44044 netlink: add support for formatted extack messages

:::::: TO: Edward Cree <ecree.xilinx@xxxxxxxxx>
:::::: CC: Jakub Kicinski <kuba@xxxxxxxxxx>

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