From 60f1692d8feb508a4f6db59099e1c831075f4466 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 10:56:33 -0500 Subject: [PATCH 1/8] Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put jira VULN-155527 cve-pre CVE-2022-50386 commit-author Luiz Augusto von Dentz commit d0be8347c623e0ac4202a1d4e0373882821f56b0 This fixes the following trace which is caused by hci_rx_work starting up *after* the final channel reference has been put() during sock_close() but *before* the references to the channel have been destroyed, so instead the code now rely on kref_get_unless_zero/l2cap_chan_hold_unless_zero to prevent referencing a channel that is about to be destroyed. refcount_t: increment on 0; use-after-free. BUG: KASAN: use-after-free in refcount_dec_and_test+0x20/0xd0 Read of size 4 at addr ffffffc114f5bf18 by task kworker/u17:14/705 CPU: 4 PID: 705 Comm: kworker/u17:14 Tainted: G S W 4.14.234-00003-g1fb6d0bd49a4-dirty #28 Hardware name: Qualcomm Technologies, Inc. SM8150 V2 PM8150 Google Inc. MSM sm8150 Flame DVT (DT) Workqueue: hci0 hci_rx_work Call trace: dump_backtrace+0x0/0x378 show_stack+0x20/0x2c dump_stack+0x124/0x148 print_address_description+0x80/0x2e8 __kasan_report+0x168/0x188 kasan_report+0x10/0x18 __asan_load4+0x84/0x8c refcount_dec_and_test+0x20/0xd0 l2cap_chan_put+0x48/0x12c l2cap_recv_frame+0x4770/0x6550 l2cap_recv_acldata+0x44c/0x7a4 hci_acldata_packet+0x100/0x188 hci_rx_work+0x178/0x23c process_one_work+0x35c/0x95c worker_thread+0x4cc/0x960 kthread+0x1a8/0x1c4 ret_from_fork+0x10/0x18 Cc: stable@kernel.org Reported-by: Lee Jones Signed-off-by: Luiz Augusto von Dentz Tested-by: Lee Jones Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit d0be8347c623e0ac4202a1d4e0373882821f56b0) Signed-off-by: Brett Mastbergen --- include/net/bluetooth/l2cap.h | 1 + net/bluetooth/l2cap_core.c | 61 +++++++++++++++++++++++++++-------- 2 files changed, 49 insertions(+), 13 deletions(-) diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h index 48ac89cbc837d..6a73eab415617 100644 --- a/include/net/bluetooth/l2cap.h +++ b/include/net/bluetooth/l2cap.h @@ -807,6 +807,7 @@ enum { }; void l2cap_chan_hold(struct l2cap_chan *c); +struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c); void l2cap_chan_put(struct l2cap_chan *c); static inline void l2cap_chan_lock(struct l2cap_chan *chan) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index f211e134cc0c9..63fc26eaa41b8 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -114,7 +114,8 @@ static struct l2cap_chan *__l2cap_get_chan_by_scid(struct l2cap_conn *conn, } /* Find channel with given SCID. - * Returns locked channel. */ + * Returns a reference locked channel. + */ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, u16 cid) { @@ -122,15 +123,19 @@ static struct l2cap_chan *l2cap_get_chan_by_scid(struct l2cap_conn *conn, mutex_lock(&conn->chan_lock); c = __l2cap_get_chan_by_scid(conn, cid); - if (c) - l2cap_chan_lock(c); + if (c) { + /* Only lock if chan reference is not 0 */ + c = l2cap_chan_hold_unless_zero(c); + if (c) + l2cap_chan_lock(c); + } mutex_unlock(&conn->chan_lock); return c; } /* Find channel with given DCID. - * Returns locked channel. + * Returns a reference locked channel. */ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn, u16 cid) @@ -139,8 +144,12 @@ static struct l2cap_chan *l2cap_get_chan_by_dcid(struct l2cap_conn *conn, mutex_lock(&conn->chan_lock); c = __l2cap_get_chan_by_dcid(conn, cid); - if (c) - l2cap_chan_lock(c); + if (c) { + /* Only lock if chan reference is not 0 */ + c = l2cap_chan_hold_unless_zero(c); + if (c) + l2cap_chan_lock(c); + } mutex_unlock(&conn->chan_lock); return c; @@ -165,8 +174,12 @@ static struct l2cap_chan *l2cap_get_chan_by_ident(struct l2cap_conn *conn, mutex_lock(&conn->chan_lock); c = __l2cap_get_chan_by_ident(conn, ident); - if (c) - l2cap_chan_lock(c); + if (c) { + /* Only lock if chan reference is not 0 */ + c = l2cap_chan_hold_unless_zero(c); + if (c) + l2cap_chan_lock(c); + } mutex_unlock(&conn->chan_lock); return c; @@ -487,6 +500,16 @@ void l2cap_chan_hold(struct l2cap_chan *c) kref_get(&c->kref); } +struct l2cap_chan *l2cap_chan_hold_unless_zero(struct l2cap_chan *c) +{ + BT_DBG("chan %p orig refcnt %u", c, kref_read(&c->kref)); + + if (!kref_get_unless_zero(&c->kref)) + return NULL; + + return c; +} + void l2cap_chan_put(struct l2cap_chan *c) { BT_DBG("chan %p orig refcnt %d", c, kref_read(&c->kref)); @@ -1800,7 +1823,10 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, src_match = !bacmp(&c->src, src); dst_match = !bacmp(&c->dst, dst); if (src_match && dst_match) { - l2cap_chan_hold(c); + c = l2cap_chan_hold_unless_zero(c); + if (!c) + continue; + read_unlock(&chan_list_lock); return c; } @@ -1815,7 +1841,7 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, } if (c1) - l2cap_chan_hold(c1); + c1 = l2cap_chan_hold_unless_zero(c1); read_unlock(&chan_list_lock); @@ -4190,6 +4216,7 @@ static inline int l2cap_config_req(struct l2cap_conn *conn, unlock: l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return err; } @@ -4302,6 +4329,7 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, done: l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return err; } @@ -5026,6 +5054,7 @@ static inline int l2cap_move_channel_req(struct l2cap_conn *conn, l2cap_send_move_chan_rsp(chan, result); l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return 0; } @@ -5118,6 +5147,7 @@ static void l2cap_move_continue(struct l2cap_conn *conn, u16 icid, u16 result) } l2cap_chan_unlock(chan); + l2cap_chan_put(chan); } static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid, @@ -5147,6 +5177,7 @@ static void l2cap_move_fail(struct l2cap_conn *conn, u8 ident, u16 icid, l2cap_send_move_chan_cfm(chan, L2CAP_MC_UNCONFIRMED); l2cap_chan_unlock(chan); + l2cap_chan_put(chan); } static int l2cap_move_channel_rsp(struct l2cap_conn *conn, @@ -5210,6 +5241,7 @@ static int l2cap_move_channel_confirm(struct l2cap_conn *conn, l2cap_send_move_chan_cfm_rsp(conn, cmd->ident, icid); l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return 0; } @@ -5245,6 +5277,7 @@ static inline int l2cap_move_channel_confirm_rsp(struct l2cap_conn *conn, } l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return 0; } @@ -5630,12 +5663,11 @@ static inline int l2cap_le_credits(struct l2cap_conn *conn, if (credits > max_credits) { BT_ERR("LE credits overflow"); l2cap_send_disconn_req(chan, ECONNRESET); - l2cap_chan_unlock(chan); /* Return 0 so that we don't trigger an unnecessary * command reject packet. */ - return 0; + goto unlock; } chan->tx_credits += credits; @@ -5648,7 +5680,9 @@ static inline int l2cap_le_credits(struct l2cap_conn *conn, if (chan->tx_credits) chan->ops->resume(chan); +unlock: l2cap_chan_unlock(chan); + l2cap_chan_put(chan); return 0; } @@ -6970,6 +7004,7 @@ static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid, done: l2cap_chan_unlock(chan); + l2cap_chan_put(chan); } static void l2cap_conless_channel(struct l2cap_conn *conn, __le16 psm, @@ -7374,7 +7409,7 @@ static struct l2cap_chan *l2cap_global_fixed_chan(struct l2cap_chan *c, if (src_type != c->src_type) continue; - l2cap_chan_hold(c); + c = l2cap_chan_hold_unless_zero(c); read_unlock(&chan_list_lock); return c; } From 59f1178f7bea82ed8b735dcab039351bced2aedc Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 11:04:32 -0500 Subject: [PATCH 2/8] Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regression jira VULN-155527 cve-pre CVE-2022-50386 commit-author Luiz Augusto von Dentz commit 332f1795ca202489c665a75e62e18ff6284de077 The patch d0be8347c623: "Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put" from Jul 21, 2022, leads to the following Smatch static checker warning: net/bluetooth/l2cap_core.c:1977 l2cap_global_chan_by_psm() error: we previously assumed 'c' could be null (see line 1996) Fixes: d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put") Reported-by: Dan Carpenter Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit 332f1795ca202489c665a75e62e18ff6284de077) Signed-off-by: Brett Mastbergen --- net/bluetooth/l2cap_core.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 63fc26eaa41b8..79a6e3b8d0be6 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1801,11 +1801,11 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, bdaddr_t *dst, u8 link_type) { - struct l2cap_chan *c, *c1 = NULL; + struct l2cap_chan *c, *tmp, *c1 = NULL; read_lock(&chan_list_lock); - list_for_each_entry(c, &chan_list, global_l) { + list_for_each_entry_safe(c, tmp, &chan_list, global_l) { if (state && c->state != state) continue; @@ -1824,11 +1824,10 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, dst_match = !bacmp(&c->dst, dst); if (src_match && dst_match) { c = l2cap_chan_hold_unless_zero(c); - if (!c) - continue; - - read_unlock(&chan_list_lock); - return c; + if (c) { + read_unlock(&chan_list_lock); + return c; + } } /* Closest match */ From f02ba3ae337f68e272e500350093fb838bb0b429 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 11:14:31 -0500 Subject: [PATCH 3/8] Bluetooth: L2CAP: Fix build errors in some archs jira VULN-155527 cve-pre CVE-2022-50386 commit-author Luiz Augusto von Dentz commit fc5ae5b44eb26db973a6d4cfa0f75fe0650a95c6 This attempts to fix the follow errors: In function 'memcmp', inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9, inlined from 'l2cap_global_chan_by_psm' at net/bluetooth/l2cap_core.c:2003:15: ./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp' specified bound 6 exceeds source size 0 [-Werror=stringop-overread] 44 | #define __underlying_memcmp __builtin_memcmp | ^ ./include/linux/fortify-string.h:420:16: note: in expansion of macro '__underlying_memcmp' 420 | return __underlying_memcmp(p, q, size); | ^~~~~~~~~~~~~~~~~~~ In function 'memcmp', inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9, inlined from 'l2cap_global_chan_by_psm' at net/bluetooth/l2cap_core.c:2004:15: ./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp' specified bound 6 exceeds source size 0 [-Werror=stringop-overread] 44 | #define __underlying_memcmp __builtin_memcmp | ^ ./include/linux/fortify-string.h:420:16: note: in expansion of macro '__underlying_memcmp' 420 | return __underlying_memcmp(p, q, size); | ^~~~~~~~~~~~~~~~~~~ Fixes: 332f1795ca20 ("Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regression") Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit fc5ae5b44eb26db973a6d4cfa0f75fe0650a95c6) Signed-off-by: Brett Mastbergen --- net/bluetooth/l2cap_core.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 79a6e3b8d0be6..67bff478221cc 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -1823,11 +1823,11 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm, src_match = !bacmp(&c->src, src); dst_match = !bacmp(&c->dst, dst); if (src_match && dst_match) { - c = l2cap_chan_hold_unless_zero(c); - if (c) { - read_unlock(&chan_list_lock); - return c; - } + if (!l2cap_chan_hold_unless_zero(c)) + continue; + + read_unlock(&chan_list_lock); + return c; } /* Closest match */ From b837f835eabb0781957d7c128ed583deea1e7e8b Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 10:45:47 -0500 Subject: [PATCH 4/8] Bluetooth: L2CAP: Fix user-after-free jira VULN-155527 cve CVE-2022-50386 commit-author Luiz Augusto von Dentz commit 35fcbc4243aad7e7d020b7c1dfb14bb888b20a4f This uses l2cap_chan_hold_unless_zero() after calling __l2cap_get_chan_blah() to prevent the following trace: Bluetooth: l2cap_core.c:static void l2cap_chan_destroy(struct kref *kref) Bluetooth: chan 0000000023c4974d Bluetooth: parent 00000000ae861c08 ================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:191 [inline] BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:671 [inline] BUG: KASAN: use-after-free in __mutex_lock+0x278/0x400 kernel/locking/mutex.c:729 Read of size 8 at addr ffff888006a49b08 by task kworker/u3:2/389 Link: https://lore.kernel.org/lkml/20220622082716.478486-1-lee.jones@linaro.org Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sungwoo Kim (cherry picked from commit 35fcbc4243aad7e7d020b7c1dfb14bb888b20a4f) Signed-off-by: Brett Mastbergen --- net/bluetooth/l2cap_core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 67bff478221cc..5d09c7ddd5171 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4032,6 +4032,12 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, } } + chan = l2cap_chan_hold_unless_zero(chan); + if (!chan) { + err = -EBADSLT; + goto unlock; + } + err = 0; l2cap_chan_lock(chan); @@ -4062,6 +4068,7 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, } l2cap_chan_unlock(chan); + l2cap_chan_put(chan); unlock: mutex_unlock(&conn->chan_lock); From dcd9e0a158c6e33ac0164f478e4ccb2cadfd5b7c Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 11:05:37 -0500 Subject: [PATCH 5/8] Bluetooth: L2CAP: fix use-after-free in l2cap_conn_del() jira VULN-7664 cve CVE-2022-3640 commit-author Zhengchao Shao commit 0d0e2d032811280b927650ff3c15fe5020e82533 When l2cap_recv_frame() is invoked to receive data, and the cid is L2CAP_CID_A2MP, if the channel does not exist, it will create a channel. However, after a channel is created, the hold operation of the channel is not performed. In this case, the value of channel reference counting is 1. As a result, after hci_error_reset() is triggered, l2cap_conn_del() invokes the close hook function of A2MP to release the channel. Then l2cap_chan_unlock(chan) will trigger UAF issue. The process is as follows: Receive data: l2cap_data_channel() a2mp_channel_create() --->channel ref is 2 l2cap_chan_put() --->channel ref is 1 Triger event: hci_error_reset() hci_dev_do_close() ... l2cap_disconn_cfm() l2cap_conn_del() l2cap_chan_hold() --->channel ref is 2 l2cap_chan_del() --->channel ref is 1 a2mp_chan_close_cb() --->channel ref is 0, release channel l2cap_chan_unlock() --->UAF of channel The detailed Call Trace is as follows: BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0xa6/0x5e0 Read of size 8 at addr ffff8880160664b8 by task kworker/u11:1/7593 Workqueue: hci0 hci_error_reset Call Trace: dump_stack_lvl+0xcd/0x134 print_report.cold+0x2ba/0x719 kasan_report+0xb1/0x1e0 kasan_check_range+0x140/0x190 __mutex_unlock_slowpath+0xa6/0x5e0 l2cap_conn_del+0x404/0x7b0 l2cap_disconn_cfm+0x8c/0xc0 hci_conn_hash_flush+0x11f/0x260 hci_dev_close_sync+0x5f5/0x11f0 hci_dev_do_close+0x2d/0x70 hci_error_reset+0x9e/0x140 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 Allocated by task 7593: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0xa9/0xd0 l2cap_chan_create+0x40/0x930 amp_mgr_create+0x96/0x990 a2mp_channel_create+0x7d/0x150 l2cap_recv_frame+0x51b8/0x9a70 l2cap_recv_acldata+0xaa3/0xc00 hci_rx_work+0x702/0x1220 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 Freed by task 7593: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 ____kasan_slab_free+0x167/0x1c0 slab_free_freelist_hook+0x89/0x1c0 kfree+0xe2/0x580 l2cap_chan_put+0x22a/0x2d0 l2cap_conn_del+0x3fc/0x7b0 l2cap_disconn_cfm+0x8c/0xc0 hci_conn_hash_flush+0x11f/0x260 hci_dev_close_sync+0x5f5/0x11f0 hci_dev_do_close+0x2d/0x70 hci_error_reset+0x9e/0x140 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0xbe/0xd0 call_rcu+0x99/0x740 netlink_release+0xe6a/0x1cf0 __sock_release+0xcd/0x280 sock_close+0x18/0x20 __fput+0x27c/0xa90 task_work_run+0xdd/0x1a0 exit_to_user_mode_prepare+0x23c/0x250 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x42/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0xbe/0xd0 call_rcu+0x99/0x740 netlink_release+0xe6a/0x1cf0 __sock_release+0xcd/0x280 sock_close+0x18/0x20 __fput+0x27c/0xa90 task_work_run+0xdd/0x1a0 exit_to_user_mode_prepare+0x23c/0x250 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x42/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put") Signed-off-by: Zhengchao Shao Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit 0d0e2d032811280b927650ff3c15fe5020e82533) Signed-off-by: Brett Mastbergen --- net/bluetooth/l2cap_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 5d09c7ddd5171..b2e0c120813ca 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -6952,6 +6952,7 @@ static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid, return; } + l2cap_chan_hold(chan); l2cap_chan_lock(chan); } else { BT_DBG("unknown cid 0x%4.4x", cid); From cffdec228a7136bc73e8b639d28ca4cccd597ce6 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 10:45:57 -0500 Subject: [PATCH 6/8] Bluetooth: L2CAP: Fix use-after-free jira VULN-155015 cve CVE-2023-53305 commit-author Zhengping Jiang commit f752a0b334bb95fe9b42ecb511e0864e2768046f Fix potential use-after-free in l2cap_le_command_rej. Signed-off-by: Zhengping Jiang Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Jakub Kicinski (cherry picked from commit f752a0b334bb95fe9b42ecb511e0864e2768046f) Signed-off-by: Brett Mastbergen --- net/bluetooth/l2cap_core.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index b2e0c120813ca..99a938962c973 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5709,9 +5709,14 @@ static inline int l2cap_le_command_rej(struct l2cap_conn *conn, if (!chan) goto done; + chan = l2cap_chan_hold_unless_zero(chan); + if (!chan) + goto done; + l2cap_chan_lock(chan); l2cap_chan_del(chan, ECONNREFUSED); l2cap_chan_unlock(chan); + l2cap_chan_put(chan); done: mutex_unlock(&conn->chan_lock); From 9070c051c61de79120d3dc51f41b33d07e4c3cca Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 10:45:53 -0500 Subject: [PATCH 7/8] wifi: brcmfmac: fix use-after-free bug in brcmf_netdev_start_xmit() jira VULN-155632 cve CVE-2022-50408 commit-author Alexander Coffin commit 3f42faf6db431e04bf942d2ebe3ae88975723478 > ret = brcmf_proto_tx_queue_data(drvr, ifp->ifidx, skb); may be schedule, and then complete before the line > ndev->stats.tx_bytes += skb->len; [ 46.912801] ================================================================== [ 46.920552] BUG: KASAN: use-after-free in brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac] [ 46.928673] Read of size 4 at addr ffffff803f5882e8 by task systemd-resolve/328 [ 46.935991] [ 46.937514] CPU: 1 PID: 328 Comm: systemd-resolve Tainted: G O 5.4.199-[REDACTED] #1 [ 46.947255] Hardware name: [REDACTED] [ 46.954568] Call trace: [ 46.957037] dump_backtrace+0x0/0x2b8 [ 46.960719] show_stack+0x24/0x30 [ 46.964052] dump_stack+0x128/0x194 [ 46.967557] print_address_description.isra.0+0x64/0x380 [ 46.972877] __kasan_report+0x1d4/0x240 [ 46.976723] kasan_report+0xc/0x18 [ 46.980138] __asan_report_load4_noabort+0x18/0x20 [ 46.985027] brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac] [ 46.990613] dev_hard_start_xmit+0x1bc/0xda0 [ 46.994894] sch_direct_xmit+0x198/0xd08 [ 46.998827] __qdisc_run+0x37c/0x1dc0 [ 47.002500] __dev_queue_xmit+0x1528/0x21f8 [ 47.006692] dev_queue_xmit+0x24/0x30 [ 47.010366] neigh_resolve_output+0x37c/0x678 [ 47.014734] ip_finish_output2+0x598/0x2458 [ 47.018927] __ip_finish_output+0x300/0x730 [ 47.023118] ip_output+0x2e0/0x430 [ 47.026530] ip_local_out+0x90/0x140 [ 47.030117] igmpv3_sendpack+0x14c/0x228 [ 47.034049] igmpv3_send_cr+0x384/0x6b8 [ 47.037895] igmp_ifc_timer_expire+0x4c/0x118 [ 47.042262] call_timer_fn+0x1cc/0xbe8 [ 47.046021] __run_timers+0x4d8/0xb28 [ 47.049693] run_timer_softirq+0x24/0x40 [ 47.053626] __do_softirq+0x2c0/0x117c [ 47.057387] irq_exit+0x2dc/0x388 [ 47.060715] __handle_domain_irq+0xb4/0x158 [ 47.064908] gic_handle_irq+0x58/0xb0 [ 47.068581] el0_irq_naked+0x50/0x5c [ 47.072162] [ 47.073665] Allocated by task 328: [ 47.077083] save_stack+0x24/0xb0 [ 47.080410] __kasan_kmalloc.isra.0+0xc0/0xe0 [ 47.084776] kasan_slab_alloc+0x14/0x20 [ 47.088622] kmem_cache_alloc+0x15c/0x468 [ 47.092643] __alloc_skb+0xa4/0x498 [ 47.096142] igmpv3_newpack+0x158/0xd78 [ 47.099987] add_grhead+0x210/0x288 [ 47.103485] add_grec+0x6b0/0xb70 [ 47.106811] igmpv3_send_cr+0x2e0/0x6b8 [ 47.110657] igmp_ifc_timer_expire+0x4c/0x118 [ 47.115027] call_timer_fn+0x1cc/0xbe8 [ 47.118785] __run_timers+0x4d8/0xb28 [ 47.122457] run_timer_softirq+0x24/0x40 [ 47.126389] __do_softirq+0x2c0/0x117c [ 47.130142] [ 47.131643] Freed by task 180: [ 47.134712] save_stack+0x24/0xb0 [ 47.138041] __kasan_slab_free+0x108/0x180 [ 47.142146] kasan_slab_free+0x10/0x18 [ 47.145904] slab_free_freelist_hook+0xa4/0x1b0 [ 47.150444] kmem_cache_free+0x8c/0x528 [ 47.154292] kfree_skbmem+0x94/0x108 [ 47.157880] consume_skb+0x10c/0x5a8 [ 47.161466] __dev_kfree_skb_any+0x88/0xa0 [ 47.165598] brcmu_pkt_buf_free_skb+0x44/0x68 [brcmutil] [ 47.171023] brcmf_txfinalize+0xec/0x190 [brcmfmac] [ 47.176016] brcmf_proto_bcdc_txcomplete+0x1c0/0x210 [brcmfmac] [ 47.182056] brcmf_sdio_sendfromq+0x8dc/0x1e80 [brcmfmac] [ 47.187568] brcmf_sdio_dpc+0xb48/0x2108 [brcmfmac] [ 47.192529] brcmf_sdio_dataworker+0xc8/0x238 [brcmfmac] [ 47.197859] process_one_work+0x7fc/0x1a80 [ 47.201965] worker_thread+0x31c/0xc40 [ 47.205726] kthread+0x2d8/0x370 [ 47.208967] ret_from_fork+0x10/0x18 [ 47.212546] [ 47.214051] The buggy address belongs to the object at ffffff803f588280 [ 47.214051] which belongs to the cache skbuff_head_cache of size 208 [ 47.227086] The buggy address is located 104 bytes inside of [ 47.227086] 208-byte region [ffffff803f588280, ffffff803f588350) [ 47.238814] The buggy address belongs to the page: [ 47.243618] page:ffffffff00dd6200 refcount:1 mapcount:0 mapping:ffffff804b6bf800 index:0xffffff803f589900 compound_mapcount: 0 [ 47.255007] flags: 0x10200(slab|head) [ 47.258689] raw: 0000000000010200 ffffffff00dfa980 0000000200000002 ffffff804b6bf800 [ 47.266439] raw: ffffff803f589900 0000000080190018 00000001ffffffff 0000000000000000 [ 47.274180] page dumped because: kasan: bad access detected [ 47.279752] [ 47.281251] Memory state around the buggy address: [ 47.286051] ffffff803f588180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 47.293277] ffffff803f588200: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 47.300502] >ffffff803f588280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 47.307723] ^ [ 47.314343] ffffff803f588300: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc [ 47.321569] ffffff803f588380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 47.328789] ================================================================== Signed-off-by: Alexander Coffin Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20220808174925.3922558-1-alex.coffin@matician.com (cherry picked from commit 3f42faf6db431e04bf942d2ebe3ae88975723478) Signed-off-by: Brett Mastbergen --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c index b8f6a4a460586..da1ce128c13a1 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c @@ -200,6 +200,7 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff *skb, struct brcmf_pub *drvr = ifp->drvr; struct ethhdr *eh; int head_delta; + unsigned int tx_bytes = skb->len; brcmf_dbg(DATA, "Enter, bsscfgidx=%d\n", ifp->bsscfgidx); @@ -254,7 +255,7 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff *skb, ndev->stats.tx_dropped++; } else { ndev->stats.tx_packets++; - ndev->stats.tx_bytes += skb->len; + ndev->stats.tx_bytes += tx_bytes; } /* Return ok: we always eat the packet */ From 456264b28773c29d13db5c3652ab7afd61cb38f8 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 11 Dec 2025 10:46:03 -0500 Subject: [PATCH 8/8] ip6mr: Fix skb_under_panic in ip6mr_cache_report() jira VULN-155436 cve CVE-2023-53365 commit-author Yue Haibing commit 30e0191b16e8a58e4620fa3e2839ddc7b9d4281c skbuff: skb_under_panic: text:ffffffff88771f69 len:56 put:-4 head:ffff88805f86a800 data:ffff887f5f86a850 tail:0x88 end:0x2c0 dev:pim6reg ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:192! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 2 PID: 22968 Comm: kworker/2:11 Not tainted 6.5.0-rc3-00044-g0a8db05b571a #236 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x152/0x1d0 Call Trace: skb_push+0xc4/0xe0 ip6mr_cache_report+0xd69/0x19b0 reg_vif_xmit+0x406/0x690 dev_hard_start_xmit+0x17e/0x6e0 __dev_queue_xmit+0x2d6a/0x3d20 vlan_dev_hard_start_xmit+0x3ab/0x5c0 dev_hard_start_xmit+0x17e/0x6e0 __dev_queue_xmit+0x2d6a/0x3d20 neigh_connected_output+0x3ed/0x570 ip6_finish_output2+0x5b5/0x1950 ip6_finish_output+0x693/0x11c0 ip6_output+0x24b/0x880 NF_HOOK.constprop.0+0xfd/0x530 ndisc_send_skb+0x9db/0x1400 ndisc_send_rs+0x12a/0x6c0 addrconf_dad_completed+0x3c9/0xea0 addrconf_dad_work+0x849/0x1420 process_one_work+0xa22/0x16e0 worker_thread+0x679/0x10c0 ret_from_fork+0x28/0x60 ret_from_fork_asm+0x11/0x20 When setup a vlan device on dev pim6reg, DAD ns packet may sent on reg_vif_xmit(). reg_vif_xmit() ip6mr_cache_report() skb_push(skb, -skb_network_offset(pkt));//skb_network_offset(pkt) is 4 And skb_push declared as: void *skb_push(struct sk_buff *skb, unsigned int len); skb->data -= len; //0xffff88805f86a84c - 0xfffffffc = 0xffff887f5f86a850 skb->data is set to 0xffff887f5f86a850, which is invalid mem addr, lead to skb_push() fails. Fixes: 14fb64e1f449 ("[IPV6] MROUTE: Support PIM-SM (SSM).") Signed-off-by: Yue Haibing Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller (cherry picked from commit 30e0191b16e8a58e4620fa3e2839ddc7b9d4281c) Signed-off-by: Brett Mastbergen --- net/ipv6/ip6mr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index 296861e23b0d9..b73154923ee3b 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -1163,7 +1163,7 @@ static int ip6mr_cache_report(struct mr6_table *mrt, struct sk_buff *pkt, And all this only to mangle msg->im6_msgtype and to set msg->im6_mbz to "mbz" :-) */ - skb_push(skb, -skb_network_offset(pkt)); + __skb_pull(skb, skb_network_offset(pkt)); skb_push(skb, sizeof(*msg)); skb_reset_transport_header(skb);