From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE3D23B95E4; Sat, 17 Oct 2026 17:10:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792257040; cv=none; b=ghIdEUINRuxwnSn+nGDXYePztl/AQuoH+IcHlcZiQ6PFCxqoRwNZzdgNde1hDEZ7KtO56f7u0tM4idyaCLzqSg0OOxib5qFcewLb6jouY7B+GnhWQuiHWP0KHxf8uVKmOBpL2PUWiC0Y2kOR/lZ3112cEDKIHzE+1HnYc5fz5rI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792257040; c=relaxed/simple; bh=9vfAApinIyHrkl+YedU50l2T08AquHLefcGRJBLj/rM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=raP0D43K4icoP2m0gsg/8D+ObwJpm+mZkibONun30ovEF+TSSnpU48sii8tWDX2J7xab9tpYKrUE201JpwNLJJgFxmjkK145sQtbWc3uvcLn5Y1Cc/QD0zWff69gCjYLQ8MoQ2Sqo9dnaUHEhHZUGuGgE3LSPNr447dk5VRb5DA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AgMh6Rbs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="AgMh6Rbs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 332BB1F000C4; Sat, 17 Oct 2026 17:10:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792257038; bh=2Rv+2cGL9Knk3jJmQkv/9cwfOeqVDCRq4C4/EiVyJHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AgMh6RbsL2fWWTciN282CGz7b38B+OkFFuBJyIBmkKMdLip4pKaWzshHx5+/CLSa/ OqQ4Aa0KTy0iPYXLWGHBSz21AqtbkdhWbLd8ZpnDRYIMYuhalLtogSGemoqSezeajB GGmsjkqFK7u/zpk2yCkhXPlXOR1uk3ugI98F1en8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vega , Zhiling Zou , Johannes Berg , Sasha Levin Subject: [PATCH 6.6 0430/1674] wifi: mac80211: count only matching reservations in reserved switch Date: Sat, 17 Oct 2026 17:45:02 +0200 Message-ID: <20261017160442.163082283@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zhiling Zou [ Upstream commit 437f3727b4fd715266c296435c116288f82666fd ] ieee80211_vif_use_reserved_switch() validates a replacement by counting assigned links on ctx->replace_ctx and treating reservations too broadly. A link can still be assigned to the old channel context while holding a reservation that belongs to a different replacement operation. That can make the current replacement appear complete too early. If another link finalizes first, the function can free the WILL_BE_REPLACED chanctx while the unmatched link and driver still use it, leading to a use-after-free in later beacon generation. Require an in-place reservation to point at the current replacement context, and require the reserved and assigned contexts to be the matching replacement pair, before counting or moving the link. Fixes: 5bcae31d9cb1 ("mac80211: implement multi-vif in-place reservations") Cc: stable@vger.kernel.org Reported-by: Vega Signed-off-by: Zhiling Zou Link: https://patch.msgid.link/4b6c4b8648ab1920c38a40be32c0b1a2797b4ac6.1785726007.git.zhilinz@nebusec.ai Signed-off-by: Johannes Berg [ sashal: Adapted channel-context iterators to direct link-list traversal. ] Signed-off-by: Sasha Levin --- net/mac80211/chan.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 85875ed7536f8..29a6ad65c9a8b 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -1394,7 +1394,8 @@ ieee80211_link_use_reserved_assign(struct ieee80211_link_data *link) } static bool -ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link) +ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link, + struct ieee80211_chanctx *ctx) { struct ieee80211_sub_if_data *sdata = link->sdata; struct ieee80211_chanctx *old_ctx, *new_ctx; @@ -1404,6 +1405,9 @@ ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link) new_ctx = link->reserved_chanctx; old_ctx = ieee80211_link_get_chanctx(link); + if (new_ctx != ctx) + return false; + if (!old_ctx) return false; @@ -1416,6 +1420,12 @@ ieee80211_link_has_in_place_reservation(struct ieee80211_link_data *link) if (new_ctx->replace_state != IEEE80211_CHANCTX_REPLACES_OTHER) return false; + if (new_ctx->replace_ctx != old_ctx) + return false; + + if (old_ctx->replace_ctx != new_ctx) + return false; + return true; } @@ -1465,7 +1475,7 @@ static int ieee80211_chsw_switch_vifs(struct ieee80211_local *local, list_for_each_entry(link, &ctx->reserved_links, reserved_chanctx_list) { - if (!ieee80211_link_has_in_place_reservation(link)) + if (!ieee80211_link_has_in_place_reservation(link, ctx)) continue; old_ctx = ieee80211_link_get_chanctx(link); @@ -1574,7 +1584,7 @@ static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local) list_for_each_entry(link, &ctx->replace_ctx->assigned_links, assigned_chanctx_list) { n_assigned++; - if (link->reserved_chanctx) { + if (ieee80211_link_has_in_place_reservation(link, ctx)) { n_reserved++; if (link->reserved_ready) n_ready++; @@ -1595,7 +1605,7 @@ static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local) ctx->conf.radar_enabled = false; list_for_each_entry(link, &ctx->reserved_links, reserved_chanctx_list) { - if (ieee80211_link_has_in_place_reservation(link) && + if (ieee80211_link_has_in_place_reservation(link, ctx) && !link->reserved_ready) return -EAGAIN; @@ -1669,7 +1679,7 @@ static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local) struct ieee80211_bss_conf *link_conf = link->conf; u64 changed = 0; - if (!ieee80211_link_has_in_place_reservation(link)) + if (!ieee80211_link_has_in_place_reservation(link, ctx)) continue; rcu_assign_pointer(link_conf->chanctx_conf, @@ -1722,7 +1732,8 @@ static int ieee80211_vif_use_reserved_switch(struct ieee80211_local *local) */ list_for_each_entry_safe(link, link_tmp, &ctx->reserved_links, reserved_chanctx_list) { - if (WARN_ON(ieee80211_link_has_in_place_reservation(link))) + if (WARN_ON(ieee80211_link_has_in_place_reservation(link, + ctx))) continue; if (WARN_ON(link->reserved_chanctx != ctx)) -- 2.53.0