From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 13DC122370A; Mon, 23 Jun 2025 22:23:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750717407; cv=none; b=meWcGtjVCLae1brrwOeI7uRvxeNRLSfqG9/8xeB0yO+A3TWmqumSnaHfV2JbrqSLRMPrbwvWBtP8kupm8lMA+66YPl+WCubSdRCttGH8lP5B6sYDY+HpCH8KxykmJYKUtL8ULeYbo/glXLCrf6UEJm8s1NZ0wQUa93v/yzXR6HU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750717407; c=relaxed/simple; bh=C1dcoJ9uT5JvBa35RAcMKdGUTjLsWx4xr39DJ3Hlsh8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=K4QymuV7K6RwPdy99TE7il8XchEpRFiit4ax3SUt7J06oSZntPbb+OBt8FwxfwLpBLotD3QDryU9gUMdvEX7yXRwBPbggZuWT5DtWBsUmnDCzvG7lX1Xgfx83Nysk0EnCdnjzk8K4eUZ8xOzcXNJUI96bREhVLRj0QyKi9VD1SA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1dffHcJc; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1dffHcJc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C783C4CEEA; Mon, 23 Jun 2025 22:23:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750717406; bh=C1dcoJ9uT5JvBa35RAcMKdGUTjLsWx4xr39DJ3Hlsh8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1dffHcJcoxDgqArhOG8wui3jONa2ATbPIv7l+HrvLXSmS2g9SxGwKooMxDqzgSEf7 W6DezBmnjdo5xu6nhAckpZSi/lzxXRlJnQg+8XrOwlKDuwPCCs9kYe5IutHRiwm5CH ezM6LCViblUykj0eHBos7jh5iPc9aUOFhRdsgcDk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+1d3c235276f62963e93a@syzkaller.appspotmail.com, Kuniyuki Iwashima , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 381/414] atm: atmtcp: Free invalid length skb in atmtcp_c_send(). Date: Mon, 23 Jun 2025 15:08:38 +0200 Message-ID: <20250623130651.477979048@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130642.015559452@linuxfoundation.org> References: <20250623130642.015559452@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kuniyuki Iwashima [ Upstream commit 2f370ae1fb6317985f3497b1bb80d457508ca2f7 ] syzbot reported the splat below. [0] vcc_sendmsg() copies data passed from userspace to skb and passes it to vcc->dev->ops->send(). atmtcp_c_send() accesses skb->data as struct atmtcp_hdr after checking if skb->len is 0, but it's not enough. Also, when skb->len == 0, skb and sk (vcc) were leaked because dev_kfree_skb() is not called and sk_wmem_alloc adjustment is missing to revert atm_account_tx() in vcc_sendmsg(), which is expected to be done in atm_pop_raw(). Let's properly free skb with an invalid length in atmtcp_c_send(). [0]: BUG: KMSAN: uninit-value in atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294 atmtcp_c_send+0x255/0xed0 drivers/atm/atmtcp.c:294 vcc_sendmsg+0xd7c/0xff0 net/atm/common.c:644 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x330/0x3d0 net/socket.c:727 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655 x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was created at: slab_post_alloc_hook mm/slub.c:4154 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [inline] vcc_sendmsg+0xb40/0xff0 net/atm/common.c:628 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x330/0x3d0 net/socket.c:727 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655 x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f CPU: 1 UID: 0 PID: 5798 Comm: syz-executor192 Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+1d3c235276f62963e93a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1d3c235276f62963e93a Tested-by: syzbot+1d3c235276f62963e93a@syzkaller.appspotmail.com Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250616182147.963333-2-kuni1840@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/atm/atmtcp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/atm/atmtcp.c b/drivers/atm/atmtcp.c index d4aa0f353b6c8..eeae160c898d3 100644 --- a/drivers/atm/atmtcp.c +++ b/drivers/atm/atmtcp.c @@ -288,7 +288,9 @@ static int atmtcp_c_send(struct atm_vcc *vcc,struct sk_buff *skb) struct sk_buff *new_skb; int result = 0; - if (!skb->len) return 0; + if (skb->len < sizeof(struct atmtcp_hdr)) + goto done; + dev = vcc->dev_data; hdr = (struct atmtcp_hdr *) skb->data; if (hdr->length == ATMTCP_HDR_MAGIC) { -- 2.39.5 multicast.c +++ b/net/bridge/br_multicast.c @@ -4037,6 +4037,32 @@ static void __br_multicast_stop(struct net_bridge_mcast *brmctx) #endif } +void br_multicast_update_vlan_mcast_ctx(struct net_bridge_vlan *v, u8 state) +{ +#if IS_ENABLED(CONFIG_BRIDGE_VLAN_FILTERING) + struct net_bridge *br; + + if (!br_vlan_should_use(v)) + return; + + if (br_vlan_is_master(v)) + return; + + br = v->port->br; + + if (!br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED)) + return; + + if (br_vlan_state_allowed(state, true)) + br_multicast_enable_port_ctx(&v->port_mcast_ctx); + + /* Multicast is not disabled for the vlan when it goes in + * blocking state because the timers will expire and stop by + * themselves without sending more queries. + */ +#endif +} + void br_multicast_toggle_one_vlan(struct net_bridge_vlan *vlan, bool on) { struct net_bridge *br; diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 19fb505492521..767f0e81dd265 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -977,6 +977,7 @@ void br_multicast_port_ctx_init(struct net_bridge_port *port, struct net_bridge_vlan *vlan, struct net_bridge_mcast_port *pmctx); void br_multicast_port_ctx_deinit(struct net_bridge_mcast_port *pmctx); +void br_multicast_update_vlan_mcast_ctx(struct net_bridge_vlan *v, u8 state); void br_multicast_toggle_one_vlan(struct net_bridge_vlan *vlan, bool on); int br_multicast_toggle_vlan_snooping(struct net_bridge *br, bool on, struct netlink_ext_ack *extack); @@ -1403,6 +1404,11 @@ static inline void br_multicast_port_ctx_deinit(struct net_bridge_mcast_port *pm { } +static inline void br_multicast_update_vlan_mcast_ctx(struct net_bridge_vlan *v, + u8 state) +{ +} + static inline void br_multicast_toggle_one_vlan(struct net_bridge_vlan *vlan, bool on) { @@ -1752,7 +1758,9 @@ bool br_vlan_global_opts_can_enter_range(const struct net_bridge_vlan *v_curr, bool br_vlan_global_opts_fill(struct sk_buff *skb, u16 vid, u16 vid_range, const struct net_bridge_vlan *v_opts); -/* vlan state manipulation helpers using *_ONCE to annotate lock-free access */ +/* vlan state manipulation helpers using *_ONCE to annotate lock-free access, + * while br_vlan_set_state() may access data protected by multicast_lock. + */ static inline u8 br_vlan_get_state(const struct net_bridge_vlan *v) { return READ_ONCE(v->state); @@ -1761,6 +1769,7 @@ static inline u8 br_vlan_get_state(const struct net_bridge_vlan *v) static inline void br_vlan_set_state(struct net_bridge_vlan *v, u8 state) { WRITE_ONCE(v->state, state); + br_multicast_update_vlan_mcast_ctx(v, state); } static inline u8 br_vlan_get_pvid_state(const struct net_bridge_vlan_group *vg) -- 2.39.5