realtek: dsa: Build check size of drop counter names

The commit 1cfd45ae0b ("realtek: Add debugfs support for RTL9300") caused
previously an out of bounds access on the array holding the names of drop
counters (and incorrect names in the output) fur RTL839x because of a
missing comma. To avoid such situation in the future, calculate the size of
the array during compilation. And to ensure that this count matches the
actual number of counters in HW, compare this number during compile time
with the expected value.

Suggested-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Link: https://github.com/openwrt/openwrt/pull/20905
Signed-off-by: Robert Marko <robimarko@gmail.com>
This commit is contained in:
Sven Eckelmann 2025-11-24 08:54:30 +01:00 committed by Robert Marko
parent abb7bbb64a
commit 4dab2a9405

View File

@ -205,22 +205,26 @@ static ssize_t drop_counter_read(struct file *filp, char __user *buffer, size_t
case RTL8380_FAMILY_ID:
d = rtl838x_drop_cntr;
offset = RTL838X_STAT_PRVTE_DROP_COUNTERS;
num = 40;
num = ARRAY_SIZE(rtl838x_drop_cntr);
BUILD_BUG_ON(num != 40);
break;
case RTL8390_FAMILY_ID:
d = rtl839x_drop_cntr;
offset = RTL839X_STAT_PRVTE_DROP_COUNTERS;
num = 45;
num = ARRAY_SIZE(rtl839x_drop_cntr);
BUILD_BUG_ON(num != 45);
break;
case RTL9300_FAMILY_ID:
d = rtl930x_drop_cntr;
offset = RTL930X_STAT_PRVTE_DROP_COUNTERS;
num = 85;
num = ARRAY_SIZE(rtl930x_drop_cntr);
BUILD_BUG_ON(num != 85);
break;
case RTL9310_FAMILY_ID:
d = rtl931x_drop_cntr;
offset = RTL931X_STAT_PRVTE_DROP_COUNTERS;
num = 81;
num = ARRAY_SIZE(rtl931x_drop_cntr);
BUILD_BUG_ON(num != 81);
break;
}