From 453b6e62c5fbfc67d7b08d7b6f8e685d7fbb3b54 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:36:33 -0400 Subject: [PATCH 1/9] posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit jira VULN-136692 cve CVE-2025-38352 commit-author Oleg Nesterov commit f90fff1e152dedf52b932240ebbd670d83330eca If an exiting non-autoreaping task has already passed exit_notify() and calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent or debugger right after unlock_task_sighand(). If a concurrent posix_cpu_timer_del() runs at that moment, it won't be able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or lock_task_sighand() will fail. Add the tsk->exit_state check into run_posix_cpu_timers() to fix this. This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because exit_task_work() is called before exit_notify(). But the check still makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail anyway in this case. Cc: stable@vger.kernel.org Reported-by: BenoƮt Sevens Fixes: 0bdd2ed4138e ("sched: run_posix_cpu_timers: Don't check ->exit_state, use lock_task_sighand()") Signed-off-by: Oleg Nesterov Signed-off-by: Linus Torvalds (cherry picked from commit f90fff1e152dedf52b932240ebbd670d83330eca) Signed-off-by: Brett Mastbergen --- kernel/time/posix-cpu-timers.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 0a97193984dbf..7f58fddeeaae8 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -1379,6 +1379,15 @@ void run_posix_cpu_timers(void) lockdep_assert_irqs_disabled(); + /* + * Ensure that release_task(tsk) can't happen while + * handle_posix_cpu_timers() is running. Otherwise, a concurrent + * posix_cpu_timer_del() may fail to lock_task_sighand(tsk) and + * miss timer->it.cpu.firing != 0. + */ + if (tsk->exit_state) + return; + /* * If the actual expiry is deferred to task work context and the * work is already scheduled there is no point to do anything here. From c31dec07f2693d30c8e1ccd30a9650f03dee18b2 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:38:00 -0400 Subject: [PATCH 2/9] nfp: fix use-after-free in area_cache_get() jira VULN-5899 cve CVE-2022-3545 commit-author Jialiang Wang commit 02e1a114fdb71e59ee6770294166c30d437bf86a area_cache_get() is used to distribute cache->area and set cache->id, and if cache->id is not 0 and cache->area->kref refcount is 0, it will release the cache->area by nfp_cpp_area_release(). area_cache_get() set cache->id before cpp->op->area_init() and nfp_cpp_area_acquire(). But if area_init() or nfp_cpp_area_acquire() fails, the cache->id is is already set but the refcount is not increased as expected. At this time, calling the nfp_cpp_area_release() will cause use-after-free. To avoid the use-after-free, set cache->id after area_init() and nfp_cpp_area_acquire() complete successfully. Note: This vulnerability is triggerable by providing emulated device equipped with specified configuration. BUG: KASAN: use-after-free in nfp6000_area_init (drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c:760) Write of size 4 at addr ffff888005b7f4a0 by task swapper/0/1 Call Trace: nfp6000_area_init (drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c:760) area_cache_get.constprop.8 (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:884) Allocated by task 1: nfp_cpp_area_alloc_with_name (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:303) nfp_cpp_area_cache_add (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:802) nfp6000_init (drivers/net/ethernet/netronome/nfp/nfpcore/nfp6000_pcie.c:1230) nfp_cpp_from_operations (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:1215) nfp_pci_probe (drivers/net/ethernet/netronome/nfp/nfp_main.c:744) Freed by task 1: kfree (mm/slub.c:4562) area_cache_get.constprop.8 (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:873) nfp_cpp_read (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:924 drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c:973) nfp_cpp_readl (drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cpplib.c:48) Signed-off-by: Jialiang Wang Reviewed-by: Yinjun Zhang Acked-by: Simon Horman Link: https://lore.kernel.org/r/20220810073057.4032-1-wangjialiang0806@163.com Signed-off-by: Jakub Kicinski (cherry picked from commit 02e1a114fdb71e59ee6770294166c30d437bf86a) Signed-off-by: Brett Mastbergen --- drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c index 34c0d2ddf9ef6..a8286d0032d1e 100644 --- a/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c +++ b/drivers/net/ethernet/netronome/nfp/nfpcore/nfp_cppcore.c @@ -874,7 +874,6 @@ area_cache_get(struct nfp_cpp *cpp, u32 id, } /* Adjust the start address to be cache size aligned */ - cache->id = id; cache->addr = addr & ~(u64)(cache->size - 1); /* Re-init to the new ID and address */ @@ -894,6 +893,8 @@ area_cache_get(struct nfp_cpp *cpp, u32 id, return NULL; } + cache->id = id; + exit: /* Adjust offset */ *offset = addr - cache->addr; From 39feb8393c1d46f5ce874ef7bacb22eaaae8cccd Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:39:23 -0400 Subject: [PATCH 3/9] drivers: net: slip: fix NPD bug in sl_tx_timeout() jira VULN-6069 cve CVE-2022-41858 commit-author Duoming Zhou commit ec4eb8a86ade4d22633e1da2a7d85a846b7d1798 When a slip driver is detaching, the slip_close() will act to cleanup necessary resources and sl->tty is set to NULL in slip_close(). Meanwhile, the packet we transmit is blocked, sl_tx_timeout() will be called. Although slip_close() and sl_tx_timeout() use sl->lock to synchronize, we don`t judge whether sl->tty equals to NULL in sl_tx_timeout() and the null pointer dereference bug will happen. (Thread 1) | (Thread 2) | slip_close() | spin_lock_bh(&sl->lock) | ... ... | sl->tty = NULL //(1) sl_tx_timeout() | spin_unlock_bh(&sl->lock) spin_lock(&sl->lock); | ... | ... tty_chars_in_buffer(sl->tty)| if (tty->ops->..) //(2) | ... | synchronize_rcu() We set NULL to sl->tty in position (1) and dereference sl->tty in position (2). This patch adds check in sl_tx_timeout(). If sl->tty equals to NULL, sl_tx_timeout() will goto out. Signed-off-by: Duoming Zhou Reviewed-by: Jiri Slaby Link: https://lore.kernel.org/r/20220405132206.55291-1-duoming@zju.edu.cn Signed-off-by: Jakub Kicinski (cherry picked from commit ec4eb8a86ade4d22633e1da2a7d85a846b7d1798) Signed-off-by: Brett Mastbergen --- drivers/net/slip/slip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/slip/slip.c b/drivers/net/slip/slip.c index 88396ff99f03f..6865d32270e5d 100644 --- a/drivers/net/slip/slip.c +++ b/drivers/net/slip/slip.c @@ -469,7 +469,7 @@ static void sl_tx_timeout(struct net_device *dev, unsigned int txqueue) spin_lock(&sl->lock); if (netif_queue_stopped(dev)) { - if (!netif_running(dev)) + if (!netif_running(dev) || !sl->tty) goto out; /* May be we must check transmitter timeout here ? From 2f2d6fd9d700219e91d2b38fe5d7325495e39b78 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:40:50 -0400 Subject: [PATCH 4/9] bnxt: prevent skb UAF after handing over to PTP worker jira VULN-8012 cve CVE-2022-48637 commit-author Jakub Kicinski commit c31f26c8f69f776759cbbdfb38e40ea91aa0dd65 When reading the timestamp is required bnxt_tx_int() hands over the ownership of the completed skb to the PTP worker. The skb should not be used afterwards, as the worker may run before the rest of our code and free the skb, leading to a use-after-free. Since dev_kfree_skb_any() accepts NULL make the loss of ownership more obvious and set skb to NULL. Fixes: 83bb623c968e ("bnxt_en: Transmit and retrieve packet timestamps") Reviewed-by: Andy Gospodarek Reviewed-by: Michael Chan Link: https://lore.kernel.org/r/20220921201005.335390-1-kuba@kernel.org Signed-off-by: Jakub Kicinski (cherry picked from commit c31f26c8f69f776759cbbdfb38e40ea91aa0dd65) Signed-off-by: Brett Mastbergen --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 34bf1a9daae5c..3d9dacfd7bdbc 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -659,7 +659,6 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) for (i = 0; i < nr_pkts; i++) { struct bnxt_sw_tx_bd *tx_buf; - bool compl_deferred = false; struct sk_buff *skb; int j, last; @@ -668,6 +667,8 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) skb = tx_buf->skb; tx_buf->skb = NULL; + tx_bytes += skb->len; + if (tx_buf->is_push) { tx_buf->is_push = 0; goto next_tx_int; @@ -688,8 +689,9 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) } if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) { if (bp->flags & BNXT_FLAG_CHIP_P5) { + /* PTP worker takes ownership of the skb */ if (!bnxt_get_tx_ts_p5(bp, skb)) - compl_deferred = true; + skb = NULL; else atomic_inc(&bp->ptp_cfg->tx_avail); } @@ -698,9 +700,7 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) next_tx_int: cons = NEXT_TX(cons); - tx_bytes += skb->len; - if (!compl_deferred) - dev_kfree_skb_any(skb); + dev_kfree_skb_any(skb); } netdev_tx_completed_queue(txq, nr_pkts, tx_bytes); From 205d74bab85c553d1faa7ad5122dea5fa010ccb0 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:42:03 -0400 Subject: [PATCH 5/9] ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead jira VULN-70418 cve CVE-2022-49977 commit-author Yang Jihong commit c3b0f72e805f0801f05fa2aa52011c4bfc694c44 ftrace_startup does not remove ops from ftrace_ops_list when ftrace_startup_enable fails: register_ftrace_function ftrace_startup __register_ftrace_function ... add_ftrace_ops(&ftrace_ops_list, ops) ... ... ftrace_startup_enable // if ftrace failed to modify, ftrace_disabled is set to 1 ... return 0 // ops is in the ftrace_ops_list. When ftrace_disabled = 1, unregister_ftrace_function simply returns without doing anything: unregister_ftrace_function ftrace_shutdown if (unlikely(ftrace_disabled)) return -ENODEV; // return here, __unregister_ftrace_function is not executed, // as a result, ops is still in the ftrace_ops_list __unregister_ftrace_function ... If ops is dynamically allocated, it will be free later, in this case, is_ftrace_trampoline accesses NULL pointer: is_ftrace_trampoline ftrace_ops_trampoline do_for_each_ftrace_op(op, ftrace_ops_list) // OOPS! op may be NULL! Syzkaller reports as follows: [ 1203.506103] BUG: kernel NULL pointer dereference, address: 000000000000010b [ 1203.508039] #PF: supervisor read access in kernel mode [ 1203.508798] #PF: error_code(0x0000) - not-present page [ 1203.509558] PGD 800000011660b067 P4D 800000011660b067 PUD 130fb8067 PMD 0 [ 1203.510560] Oops: 0000 [#1] SMP KASAN PTI [ 1203.511189] CPU: 6 PID: 29532 Comm: syz-executor.2 Tainted: G B W 5.10.0 #8 [ 1203.512324] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 1203.513895] RIP: 0010:is_ftrace_trampoline+0x26/0xb0 [ 1203.514644] Code: ff eb d3 90 41 55 41 54 49 89 fc 55 53 e8 f2 00 fd ff 48 8b 1d 3b 35 5d 03 e8 e6 00 fd ff 48 8d bb 90 00 00 00 e8 2a 81 26 00 <48> 8b ab 90 00 00 00 48 85 ed 74 1d e8 c9 00 fd ff 48 8d bb 98 00 [ 1203.518838] RSP: 0018:ffffc900012cf960 EFLAGS: 00010246 [ 1203.520092] RAX: 0000000000000000 RBX: 000000000000007b RCX: ffffffff8a331866 [ 1203.521469] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000000010b [ 1203.522583] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8df18b07 [ 1203.523550] R10: fffffbfff1be3160 R11: 0000000000000001 R12: 0000000000478399 [ 1203.524596] R13: 0000000000000000 R14: ffff888145088000 R15: 0000000000000008 [ 1203.525634] FS: 00007f429f5f4700(0000) GS:ffff8881daf00000(0000) knlGS:0000000000000000 [ 1203.526801] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1203.527626] CR2: 000000000000010b CR3: 0000000170e1e001 CR4: 00000000003706e0 [ 1203.528611] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1203.529605] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Therefore, when ftrace_startup_enable fails, we need to rollback registration process and remove ops from ftrace_ops_list. Link: https://lkml.kernel.org/r/20220818032659.56209-1-yangjihong1@huawei.com Suggested-by: Steven Rostedt Signed-off-by: Yang Jihong Signed-off-by: Steven Rostedt (Google) (cherry picked from commit c3b0f72e805f0801f05fa2aa52011c4bfc694c44) Signed-off-by: Brett Mastbergen --- kernel/trace/ftrace.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7300743f2b799..8df057c4f418e 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3000,6 +3000,16 @@ int ftrace_startup(struct ftrace_ops *ops, int command) ftrace_startup_enable(command); + /* + * If ftrace is in an undefined state, we just remove ops from list + * to prevent the NULL pointer, instead of totally rolling it back and + * free trampoline, because those actions could cause further damage. + */ + if (unlikely(ftrace_disabled)) { + __unregister_ftrace_function(ops); + return -ENODEV; + } + ops->flags &= ~FTRACE_OPS_FL_ADDING; return 0; From fabbb1f41103fe7ab3a6e9a9be47b704ef9f1dca Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:46:47 -0400 Subject: [PATCH 6/9] drm/atomic: Fix potential use-after-free in nonblocking commits jira VULN-6740 cve CVE-2023-51043 commit-author Daniel Vetter commit 4e076c73e4f6e90816b30fcd4a0d7ab365087255 This requires a bit of background. Properly done a modeset driver's unload/remove sequence should be drm_dev_unplug(); drm_atomic_helper_shutdown(); drm_dev_put(); The trouble is that the drm_dev_unplugged() checks are by design racy, they do not synchronize against all outstanding ioctl. This is because those ioctl could block forever (both for modeset and for driver specific ioctls), leading to deadlocks in hotunplug. Instead the code sections that touch the hardware need to be annotated with drm_dev_enter/exit, to avoid accessing hardware resources after the unload/remove has finished. To avoid use-after-free issues all the involved userspace visible objects are supposed to hold a reference on the underlying drm_device, like drm_file does. The issue now is that we missed one, the atomic modeset ioctl can be run in a nonblocking fashion, and in that case it cannot rely on the implied drm_device reference provided by the ioctl calling context. This can result in a use-after-free if an nonblocking atomic commit is carefully raced against a driver unload. Fix this by unconditionally grabbing a drm_device reference for any drm_atomic_state structures. Strictly speaking this isn't required for blocking commits and TEST_ONLY calls, but it's the simpler approach. Thanks to shanzhulig for the initial idea of grabbing an unconditional reference, I just added comments, a condensed commit message and fixed a minor potential issue in where exactly we drop the final reference. Reported-by: shanzhulig Suggested-by: shanzhulig Reviewed-by: Maxime Ripard Cc: Maarten Lankhorst Cc: Thomas Zimmermann Cc: David Airlie Cc: stable@kernel.org Signed-off-by: Daniel Vetter Signed-off-by: Daniel Vetter Signed-off-by: Linus Torvalds (cherry picked from commit 4e076c73e4f6e90816b30fcd4a0d7ab365087255) Signed-off-by: Brett Mastbergen --- drivers/gpu/drm/drm_atomic.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index f197f59f6d99b..f7c5f114d883e 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -140,6 +140,12 @@ drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state) if (!state->planes) goto fail; + /* + * Because drm_atomic_state can be committed asynchronously we need our + * own reference and cannot rely on the on implied by drm_file in the + * ioctl call. + */ + drm_dev_get(dev); state->dev = dev; drm_dbg_atomic(dev, "Allocated atomic state %p\n", state); @@ -299,7 +305,8 @@ EXPORT_SYMBOL(drm_atomic_state_clear); void __drm_atomic_state_free(struct kref *ref) { struct drm_atomic_state *state = container_of(ref, typeof(*state), ref); - struct drm_mode_config *config = &state->dev->mode_config; + struct drm_device *dev = state->dev; + struct drm_mode_config *config = &dev->mode_config; drm_atomic_state_clear(state); @@ -311,6 +318,8 @@ void __drm_atomic_state_free(struct kref *ref) drm_atomic_state_default_release(state); kfree(state); } + + drm_dev_put(dev); } EXPORT_SYMBOL(__drm_atomic_state_free); From 320f150d4006e0064ddc79964c1aaa073fb2bc5f Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:48:41 -0400 Subject: [PATCH 7/9] Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg jira VULN-470 cve CVE-2023-51779 commit-author Hyunwoo Kim commit 2e07e8348ea454615e268222ae3fc240421be768 This can cause a race with bt_sock_ioctl() because bt_sock_recvmsg() gets the skb from sk->sk_receive_queue and then frees it without holding lock_sock. A use-after-free for a skb occurs with the following flow. ``` bt_sock_recvmsg() -> skb_recv_datagram() -> skb_free_datagram() bt_sock_ioctl() -> skb_peek() ``` Add lock_sock to bt_sock_recvmsg() to fix this issue. Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit 2e07e8348ea454615e268222ae3fc240421be768) Signed-off-by: Brett Mastbergen --- net/bluetooth/af_bluetooth.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index dafb06f10813f..db9fc67994624 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -264,11 +264,14 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, if (flags & MSG_OOB) return -EOPNOTSUPP; + lock_sock(sk); + skb = skb_recv_datagram(sk, flags, &err); if (!skb) { if (sk->sk_shutdown & RCV_SHUTDOWN) - return 0; + err = 0; + release_sock(sk); return err; } @@ -294,6 +297,8 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, skb_free_datagram(sk, skb); + release_sock(sk); + if (flags & MSG_TRUNC) copied = skblen; From 44a1b336251bfc5a2f6d09253c10446e0a10f06c Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:58:28 -0400 Subject: [PATCH 8/9] Bluetooth: af_bluetooth: Fix deadlock jira VULN-144746 cve CVE-2024-26886 commit-author Luiz Augusto von Dentz commit f7b94bdc1ec107c92262716b073b3e816d4784fb Attemting to do sock_lock on .recvmsg may cause a deadlock as shown bellow, so instead of using sock_sock this uses sk_receive_queue.lock on bt_sock_ioctl to avoid the UAF: INFO: task kworker/u9:1:121 blocked for more than 30 seconds. Not tainted 6.7.6-lemon #183 Workqueue: hci0 hci_rx_work Call Trace: __schedule+0x37d/0xa00 schedule+0x32/0xe0 __lock_sock+0x68/0xa0 ? __pfx_autoremove_wake_function+0x10/0x10 lock_sock_nested+0x43/0x50 l2cap_sock_recv_cb+0x21/0xa0 l2cap_recv_frame+0x55b/0x30a0 ? psi_task_switch+0xeb/0x270 ? finish_task_switch.isra.0+0x93/0x2a0 hci_rx_work+0x33a/0x3f0 process_one_work+0x13a/0x2f0 worker_thread+0x2f0/0x410 ? __pfx_worker_thread+0x10/0x10 kthread+0xe0/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2c/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 Fixes: 2e07e8348ea4 ("Bluetooth: af_bluetooth: Fix Use-After-Free in bt_sock_recvmsg") Signed-off-by: Luiz Augusto von Dentz (cherry picked from commit f7b94bdc1ec107c92262716b073b3e816d4784fb) Signed-off-by: Brett Mastbergen --- net/bluetooth/af_bluetooth.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index db9fc67994624..84dba1a3ef3b8 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -264,14 +264,11 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, if (flags & MSG_OOB) return -EOPNOTSUPP; - lock_sock(sk); - skb = skb_recv_datagram(sk, flags, &err); if (!skb) { if (sk->sk_shutdown & RCV_SHUTDOWN) err = 0; - release_sock(sk); return err; } @@ -297,8 +294,6 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, skb_free_datagram(sk, skb); - release_sock(sk); - if (flags & MSG_TRUNC) copied = skblen; @@ -521,10 +516,11 @@ int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) if (sk->sk_state == BT_LISTEN) return -EINVAL; - lock_sock(sk); + spin_lock(&sk->sk_receive_queue.lock); skb = skb_peek(&sk->sk_receive_queue); amount = skb ? skb->len : 0; - release_sock(sk); + spin_unlock(&sk->sk_receive_queue.lock); + err = put_user(amount, (int __user *)arg); break; From 0405abf43b49222b866c59ea9e4c28acbbdce693 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Tue, 9 Sep 2025 16:50:01 -0400 Subject: [PATCH 9/9] uio: Fix use-after-free in uio_open jira VULN-502 cve CVE-2023-52439 commit-author Guanghui Feng commit 0c9ae0b8605078eafc3bea053cc78791e97ba2e2 core-1 core-2 ------------------------------------------------------- uio_unregister_device uio_open idev = idr_find() device_unregister(&idev->dev) put_device(&idev->dev) uio_device_release get_device(&idev->dev) kfree(idev) uio_free_minor(minor) uio_release put_device(&idev->dev) kfree(idev) ------------------------------------------------------- In the core-1 uio_unregister_device(), the device_unregister will kfree idev when the idev->dev kobject ref is 1. But after core-1 device_unregister, put_device and before doing kfree, the core-2 may get_device. Then: 1. After core-1 kfree idev, the core-2 will do use-after-free for idev. 2. When core-2 do uio_release and put_device, the idev will be double freed. To address this issue, we can get idev atomic & inc idev reference with minor_lock. Fixes: 57c5f4df0a5a ("uio: fix crash after the device is unregistered") Cc: stable Signed-off-by: Guanghui Feng Reviewed-by: Baolin Wang Link: https://lore.kernel.org/r/1703152663-59949-1-git-send-email-guanghuifeng@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 0c9ae0b8605078eafc3bea053cc78791e97ba2e2) Signed-off-by: Brett Mastbergen --- drivers/uio/uio.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c index ea96e319c8a0e..e9b739def70e3 100644 --- a/drivers/uio/uio.c +++ b/drivers/uio/uio.c @@ -464,13 +464,13 @@ static int uio_open(struct inode *inode, struct file *filep) mutex_lock(&minor_lock); idev = idr_find(&uio_idr, iminor(inode)); - mutex_unlock(&minor_lock); if (!idev) { ret = -ENODEV; + mutex_unlock(&minor_lock); goto out; } - get_device(&idev->dev); + mutex_unlock(&minor_lock); if (!try_module_get(idev->owner)) { ret = -ENODEV; @@ -1062,9 +1062,8 @@ void uio_unregister_device(struct uio_info *info) wake_up_interruptible(&idev->wait); kill_fasync(&idev->async_queue, SIGIO, POLL_HUP); - device_unregister(&idev->dev); - uio_free_minor(minor); + device_unregister(&idev->dev); return; }