diff mbox series

[v2,1/2] net, treewide: define and use MAC_ADDR_LEN

Message ID 20250204-netconsole-v2-1-5ef5eb5f6056@purestorage.com
State Superseded
Headers show
Series netconsole: allow selection of egress interface via MAC address | expand

Commit Message

Uday Shankar Feb. 4, 2025, 9:41 p.m. UTC
There are a few places in the tree which compute the length of the
string representation of a MAC address as 3 * ETH_ALEN - 1. Define a
constant for this and use it where relevant. No functionality changes
are expected.

Signed-off-by: Uday Shankar <ushankar@purestorage.com>
---
 drivers/net/netconsole.c           | 2 +-
 drivers/nvmem/brcm_nvram.c         | 2 +-
 drivers/nvmem/layouts/u-boot-env.c | 2 +-
 include/linux/if_ether.h           | 3 +++
 lib/net_utils.c                    | 4 +---
 net/mac80211/debugfs_sta.c         | 5 +++--
 6 files changed, 10 insertions(+), 8 deletions(-)

Comments

Johannes Berg Feb. 5, 2025, 7:25 a.m. UTC | #1
On Tue, 2025-02-04 at 14:41 -0700, Uday Shankar wrote:
> There are a few places in the tree which compute the length of the
> string representation of a MAC address as 3 * ETH_ALEN - 1. Define a
> constant for this and use it where relevant. No functionality changes
> are expected.

True ... but is "MAC_ADDR_LEN" really an appropriate name for that? Just
plain reading the subject, my first thought was why you weren't going to
use ETH_ALEN.

Would seem nicer to me, at least, to have something indicating a
*string* in there, e.g. MAC_ADDR_STR_LEN or so.

johannes
kernel test robot Feb. 6, 2025, 9:31 a.m. UTC | #2
Hi Uday,

kernel test robot noticed the following build warnings:

[auto build test WARNING on c2933b2befe25309f4c5cfbea0ca80909735fd76]

url:    https://github.com/intel-lab-lkp/linux/commits/Uday-Shankar/net-treewide-define-and-use-MAC_ADDR_LEN/20250205-054620
base:   c2933b2befe25309f4c5cfbea0ca80909735fd76
patch link:    https://lore.kernel.org/r/20250204-netconsole-v2-1-5ef5eb5f6056%40purestorage.com
patch subject: [PATCH v2 1/2] net, treewide: define and use MAC_ADDR_LEN
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20250206/202502061751.GNyqzMGp-lkp@intel.com/config)
compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250206/202502061751.GNyqzMGp-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/202502061751.GNyqzMGp-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from drivers/scsi/qla4xxx/ql4_os.c:8:
   In file included from include/linux/blkdev.h:9:
   In file included from include/linux/blk_types.h:10:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/scsi/qla4xxx/ql4_os.c:15:
>> drivers/scsi/qla4xxx/ql4_def.h:148:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
     148 | #define MAC_ADDR_LEN                    6       /* in bytes */
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.
--
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8188ee/dm.c:4:
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8188ee/../wifi.h:11:
   In file included from include/linux/etherdevice.h:20:
   In file included from include/linux/if_ether.h:19:
   In file included from include/linux/skbuff.h:17:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8188ee/dm.c:8:
>> drivers/net/wireless/realtek/rtlwifi/rtl8188ee/reg.h:1230:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
    1230 | #define MAC_ADDR_LEN                            6
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.
--
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8192ee/dm.c:4:
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8192ee/../wifi.h:11:
   In file included from include/linux/etherdevice.h:20:
   In file included from include/linux/if_ether.h:19:
   In file included from include/linux/skbuff.h:17:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8192ee/dm.c:8:
>> drivers/net/wireless/realtek/rtlwifi/rtl8192ee/reg.h:1192:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
    1192 | #define MAC_ADDR_LEN                            6
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.
--
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723ae/dm.c:4:
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723ae/../wifi.h:11:
   In file included from include/linux/etherdevice.h:20:
   In file included from include/linux/if_ether.h:19:
   In file included from include/linux/skbuff.h:17:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723ae/dm.c:8:
>> drivers/net/wireless/realtek/rtlwifi/rtl8723ae/reg.h:1194:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
    1194 | #define MAC_ADDR_LEN                            6
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.
--
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723be/dm.c:4:
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723be/../wifi.h:11:
   In file included from include/linux/etherdevice.h:20:
   In file included from include/linux/if_ether.h:19:
   In file included from include/linux/skbuff.h:17:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8723be/dm.c:8:
>> drivers/net/wireless/realtek/rtlwifi/rtl8723be/reg.h:1245:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
    1245 | #define MAC_ADDR_LEN                            6
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.
--
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8821ae/dm.c:4:
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8821ae/../wifi.h:11:
   In file included from include/linux/etherdevice.h:20:
   In file included from include/linux/if_ether.h:19:
   In file included from include/linux/skbuff.h:17:
   In file included from include/linux/bvec.h:10:
   In file included from include/linux/highmem.h:8:
   In file included from include/linux/cacheflush.h:5:
   In file included from arch/x86/include/asm/cacheflush.h:5:
   In file included from include/linux/mm.h:2224:
   include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     504 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     505 |                            item];
         |                            ~~~~
   include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     511 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     512 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
     524 |         return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~ ^
     525 |                            NR_VM_NUMA_EVENT_ITEMS +
         |                            ~~~~~~~~~~~~~~~~~~~~~~
   In file included from drivers/net/wireless/realtek/rtlwifi/rtl8821ae/dm.c:8:
>> drivers/net/wireless/realtek/rtlwifi/rtl8821ae/reg.h:1274:9: warning: 'MAC_ADDR_LEN' macro redefined [-Wmacro-redefined]
    1274 | #define MAC_ADDR_LEN                    6
         |         ^
   include/linux/if_ether.h:23:9: note: previous definition is here
      23 | #define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
         |         ^
   4 warnings generated.


vim +/MAC_ADDR_LEN +148 drivers/scsi/qla4xxx/ql4_def.h

afaf5a2d341d33 David Somayajulu 2006-09-19  144  
afaf5a2d341d33 David Somayajulu 2006-09-19  145  /*
afaf5a2d341d33 David Somayajulu 2006-09-19  146   * Misc
afaf5a2d341d33 David Somayajulu 2006-09-19  147   */
afaf5a2d341d33 David Somayajulu 2006-09-19 @148  #define MAC_ADDR_LEN			6	/* in bytes */
afaf5a2d341d33 David Somayajulu 2006-09-19  149  #define IP_ADDR_LEN			4	/* in bytes */
2a49a78ed3c8d7 Vikas Chaudhary  2010-04-28  150  #define IPv6_ADDR_LEN			16	/* IPv6 address size */
afaf5a2d341d33 David Somayajulu 2006-09-19  151  #define DRIVER_NAME			"qla4xxx"
afaf5a2d341d33 David Somayajulu 2006-09-19  152
diff mbox series

Patch

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 86ab4a42769a49eebe5dd6f01dafafc6c86ec54f..78c143e65a3f337929f91f70b77e5bc88365eea7 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -675,7 +675,7 @@  static ssize_t remote_mac_store(struct config_item *item, const char *buf,
 
 	if (!mac_pton(buf, remote_mac))
 		goto out_unlock;
-	if (buf[3 * ETH_ALEN - 1] && buf[3 * ETH_ALEN - 1] != '\n')
+	if (buf[MAC_ADDR_LEN] && buf[MAC_ADDR_LEN] != '\n')
 		goto out_unlock;
 	memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
 
diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c
index b810df727b446b1762a1851750f743e0de6e8788..43608e45c58aa96a505d82733de1b24ef8d18a1b 100644
--- a/drivers/nvmem/brcm_nvram.c
+++ b/drivers/nvmem/brcm_nvram.c
@@ -100,7 +100,7 @@  static int brcm_nvram_read_post_process_macaddr(void *context, const char *id, i
 {
 	u8 mac[ETH_ALEN];
 
-	if (bytes != 3 * ETH_ALEN - 1)
+	if (bytes != MAC_ADDR_LEN)
 		return -EINVAL;
 
 	if (!mac_pton(buf, mac))
diff --git a/drivers/nvmem/layouts/u-boot-env.c b/drivers/nvmem/layouts/u-boot-env.c
index 731e6f4f12b2bf28e4547d128954a095545ad461..4a6c0d0e6dc90a138bfbb402d401d41f59c021f8 100644
--- a/drivers/nvmem/layouts/u-boot-env.c
+++ b/drivers/nvmem/layouts/u-boot-env.c
@@ -37,7 +37,7 @@  static int u_boot_env_read_post_process_ethaddr(void *context, const char *id, i
 {
 	u8 mac[ETH_ALEN];
 
-	if (bytes != 3 * ETH_ALEN - 1)
+	if (bytes != MAC_ADDR_LEN)
 		return -EINVAL;
 
 	if (!mac_pton(buf, mac))
diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 8a9792a6427ad9cf58b50c79cbfe185615800dcb..afb2fdc0af653626034ae5e19309c8427272a828 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -19,6 +19,9 @@ 
 #include <linux/skbuff.h>
 #include <uapi/linux/if_ether.h>
 
+/* XX:XX:XX:XX:XX:XX */
+#define MAC_ADDR_LEN (3 * ETH_ALEN - 1)
+
 static inline struct ethhdr *eth_hdr(const struct sk_buff *skb)
 {
 	return (struct ethhdr *)skb_mac_header(skb);
diff --git a/lib/net_utils.c b/lib/net_utils.c
index 42bb0473fb22f977409f7a6792bb1340f4e911c3..0aedd4854d85ba89dbf0e7451b3f6b197cfac1de 100644
--- a/lib/net_utils.c
+++ b/lib/net_utils.c
@@ -7,11 +7,9 @@ 
 
 bool mac_pton(const char *s, u8 *mac)
 {
-	size_t maxlen = 3 * ETH_ALEN - 1;
 	int i;
 
-	/* XX:XX:XX:XX:XX:XX */
-	if (strnlen(s, maxlen) < maxlen)
+	if (strnlen(s, MAC_ADDR_LEN) < MAC_ADDR_LEN)
 		return false;
 
 	/* Don't dirty result unless string is valid MAC. */
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index a67a9d3160086ac492d77092a0c8a74d2384b28c..29f45382367e4f6cceb0e0b5f04db1c408da712e 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -457,11 +457,12 @@  static ssize_t link_sta_addr_read(struct file *file, char __user *userbuf,
 				  size_t count, loff_t *ppos)
 {
 	struct link_sta_info *link_sta = file->private_data;
-	u8 mac[3 * ETH_ALEN + 1];
+	u8 mac[MAC_ADDR_LEN + 2];
 
 	snprintf(mac, sizeof(mac), "%pM\n", link_sta->pub->addr);
 
-	return simple_read_from_buffer(userbuf, count, ppos, mac, 3 * ETH_ALEN);
+	return simple_read_from_buffer(userbuf, count, ppos, mac,
+				       MAC_ADDR_LEN + 1);
 }
 
 LINK_STA_OPS(addr);