Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct cfg80211_scan_request. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: Paolo Abeni <pabeni@xxxxxxxxxx> Cc: linux-wireless@xxxxxxxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- include/net/cfg80211.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 6efe216c01d2..a2afc94a5408 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -2544,7 +2544,7 @@ struct cfg80211_scan_request { struct cfg80211_scan_6ghz_params *scan_6ghz_params; /* keep last */ - struct ieee80211_channel *channels[]; + struct ieee80211_channel *channels[] __counted_by(n_channels); }; static inline void get_random_mask_addr(u8 *buf, const u8 *addr, const u8 *mask) -- 2.34.1
