diff options
| author | Kees Cook <keescook@chromium.org> | 2023-08-17 14:15:23 -0700 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2023-08-22 13:18:15 +0200 |
| commit | 93ca82447c3eab149b5b2588ab8bd9aa2eacef7c (patch) | |
| tree | 728dc5b410867c34cb4ff4cb17fe8eb67fb04d12 | |
| parent | f585f4ab0b998578b4ef3610ccfc08e207fc3499 (diff) | |
| download | lwn-93ca82447c3eab149b5b2588ab8bd9aa2eacef7c.tar.gz lwn-93ca82447c3eab149b5b2588ab8bd9aa2eacef7c.zip | |
wifi: cfg80211: Annotate struct cfg80211_acl_data with __counted_by
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_acl_data.
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@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20230817211531.4193219-1-keescook@chromium.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
| -rw-r--r-- | include/net/cfg80211.h | 2 | ||||
| -rw-r--r-- | net/wireless/nl80211.c | 3 |
2 files changed, 2 insertions, 3 deletions
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index d6fa7c8767ad..eb73b5af5d04 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1282,7 +1282,7 @@ struct cfg80211_acl_data { int n_acl_entries; /* Keep it last */ - struct mac_address mac_addrs[]; + struct mac_address mac_addrs[] __counted_by(n_acl_entries); }; /** diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 8bcf8e293308..80633e815311 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -4889,13 +4889,12 @@ static struct cfg80211_acl_data *parse_acl_data(struct wiphy *wiphy, acl = kzalloc(struct_size(acl, mac_addrs, n_entries), GFP_KERNEL); if (!acl) return ERR_PTR(-ENOMEM); + acl->n_acl_entries = n_entries; nla_for_each_nested(attr, info->attrs[NL80211_ATTR_MAC_ADDRS], tmp) { memcpy(acl->mac_addrs[i].addr, nla_data(attr), ETH_ALEN); i++; } - - acl->n_acl_entries = n_entries; acl->acl_policy = acl_policy; return acl; |