| Message ID | ZxwWPrncTeSi1UTq@kspp (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Johannes Berg |
| Headers | show |
| Series | [v2] wifi: mac80211: ieee80211_i: Fix memory corruption bug in struct ieee80211_chanctx | expand |
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index e7815ffeaf30..c65adbdf2166 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -892,9 +892,10 @@ struct ieee80211_chanctx { /* temporary data for search algorithm etc. */ struct ieee80211_chan_req req; - struct ieee80211_chanctx_conf conf; - bool radar_detected; + + /* MUST be last - ends in a flexible-array member. */ + struct ieee80211_chanctx_conf conf; }; struct mac80211_qos_map {
Move the `struct ieee80211_chanctx_conf conf` to the end of `struct ieee80211_chanctx` and fix a memory corruption bug triggered in `hwsim_set_chanctx_magic()`: `radar_detected` is being overwritten when `cp->magic = HWSIM_CHANCTX_MAGIC;` See the function call sequence below: drv_add_chanctx(... struct ieee80211_chanctx *ctx) -> local->ops->add_chanctx(&local->hw, &ctx->conf) -> mac80211_hwsim_add_chanctx(... struct ieee80211_chanctx_conf *ctx) -> hwsim_set_chanctx_magic(ctx) Also, add a code comment to try to prevent people from introducing new members after `struct ieee80211_chanctx_conf conf`. Notice that `struct ieee80211_chanctx_conf` is a flexible structure --a structure that contains a flexible-array member, so it should always be at the end of any other containing structures. This change also fixes 50 of the following warnings: net/mac80211/ieee80211_i.h:895:39: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Fixes: bca8bc0399ac ("wifi: mac80211: handle ieee80211_radar_detected() for MLO") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- Changes in v2: - Add `Fixes:` tag. (Johannes) - Update Subject line and changelog text to better reflect the severity of this change. v1: - Link: https://lore.kernel.org/linux-hardening/Zxv7KtPEy1kvnTPM@kspp/ net/mac80211/ieee80211_i.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)