From f5ca4cd4c52948e5bd3980d572ea25cf2bef4854 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Wed, 11 Feb 2026 15:41:04 -0500 Subject: [PATCH 1/6] smb: client: Fix use-after-free in cifs_fill_dirent jira VULN-70861 cve CVE-2025-38051 commit-author Wang Zhaolong commit a7a8fe56e932a36f43e031b398aef92341bf5ea0 There is a race condition in the readdir concurrency process, which may access the rsp buffer after it has been released, triggering the following KASAN warning. ================================================================== BUG: KASAN: slab-use-after-free in cifs_fill_dirent+0xb03/0xb60 [cifs] Read of size 4 at addr ffff8880099b819c by task a.out/342975 CPU: 2 UID: 0 PID: 342975 Comm: a.out Not tainted 6.15.0-rc6+ #240 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Call Trace: dump_stack_lvl+0x53/0x70 print_report+0xce/0x640 kasan_report+0xb8/0xf0 cifs_fill_dirent+0xb03/0xb60 [cifs] cifs_readdir+0x12cb/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f996f64b9f9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0d f7 c3 0c 00 f7 d8 64 89 8 RSP: 002b:00007f996f53de78 EFLAGS: 00000207 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f996f53ecdc RCX: 00007f996f64b9f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f996f53dea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000207 R12: ffffffffffffff88 R13: 0000000000000000 R14: 00007ffc8cd9a500 R15: 00007f996f51e000 Allocated by task 408: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x6e/0x70 kmem_cache_alloc_noprof+0x117/0x3d0 mempool_alloc_noprof+0xf2/0x2c0 cifs_buf_get+0x36/0x80 [cifs] allocate_buffers+0x1d2/0x330 [cifs] cifs_demultiplex_thread+0x22b/0x2690 [cifs] kthread+0x394/0x720 ret_from_fork+0x34/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 342979: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x37/0x50 kmem_cache_free+0x2b8/0x500 cifs_buf_release+0x3c/0x70 [cifs] cifs_readdir+0x1c97/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents64+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff8880099b8000 which belongs to the cache cifs_request of size 16588 The buggy address is located 412 bytes inside of freed 16588-byte region [ffff8880099b8000, ffff8880099bc0cc) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99b8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 head: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea0000266e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880099b8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880099b8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880099b8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== POC is available in the link [1]. The problem triggering process is as follows: Process 1 Process 2 ----------------------------------------------------------------- cifs_readdir /* file->private_data == NULL */ initiate_cifs_search cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); smb2_query_dir_first ->query_dir_first() SMB2_query_directory SMB2_query_directory_init cifs_send_recv smb2_parse_query_directory srch_inf->ntwrk_buf_start = (char *)rsp; srch_inf->srch_entries_start = (char *)rsp + ... srch_inf->last_entry = (char *)rsp + ... srch_inf->smallBuf = true; find_cifs_entry /* if (cfile->srch_inf.ntwrk_buf_start) */ cifs_small_buf_release(cfile->srch_inf // free cifs_readdir ->iterate_shared() /* file->private_data != NULL */ find_cifs_entry /* in while (...) loop */ smb2_query_dir_next ->query_dir_next() SMB2_query_directory SMB2_query_directory_init cifs_send_recv compound_send_recv smb_send_rqst __smb_send_rqst rc = -ERESTARTSYS; /* if (fatal_signal_pending()) */ goto out; return rc /* if (cfile->srch_inf.last_entry) */ cifs_save_resume_key() cifs_fill_dirent // UAF /* if (rc) */ return -ENOENT; Fix this by ensuring the return code is checked before using pointers from the srch_inf. Link: https://bugzilla.kernel.org/show_bug.cgi?id=220131 [1] Fixes: a364bc0b37f1 ("[CIFS] fix saving of resume key before CIFSFindNext") Cc: stable@vger.kernel.org Reviewed-by: Paulo Alcantara (Red Hat) Signed-off-by: Wang Zhaolong Signed-off-by: Steve French (cherry picked from commit a7a8fe56e932a36f43e031b398aef92341bf5ea0) Signed-off-by: Brett Mastbergen --- fs/smb/client/readdir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/smb/client/readdir.c b/fs/smb/client/readdir.c index ef638086d7341..97554f768a4ee 100644 --- a/fs/smb/client/readdir.c +++ b/fs/smb/client/readdir.c @@ -786,11 +786,11 @@ find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos, rc = server->ops->query_dir_next(xid, tcon, &cfile->fid, search_flags, &cfile->srch_inf); + if (rc) + return -ENOENT; /* FindFirst/Next set last_entry to NULL on malformed reply */ if (cfile->srch_inf.last_entry) cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); - if (rc) - return -ENOENT; } if (index_to_find < cfile->srch_inf.index_of_last_entry) { /* we found the buffer that contains the entry */ From 3bf77a680e97e675a1537135f47bdb63abd879f6 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Wed, 11 Feb 2026 15:42:47 -0500 Subject: [PATCH 2/6] drm/sched: Fix potential double free in drm_sched_job_add_resv_dependencies MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit jira VULN-159552 cve CVE-2025-40096 commit-author Tvrtko Ursulin commit 5801e65206b065b0b2af032f7f1eef222aa2fd83 When adding dependencies with drm_sched_job_add_dependency(), that function consumes the fence reference both on success and failure, so in the latter case the dma_fence_put() on the error path (xarray failed to expand) is a double free. Interestingly this bug appears to have been present ever since commit ebd5f74255b9 ("drm/sched: Add dependency tracking"), since the code back then looked like this: drm_sched_job_add_implicit_dependencies(): ... for (i = 0; i < fence_count; i++) { ret = drm_sched_job_add_dependency(job, fences[i]); if (ret) break; } for (; i < fence_count; i++) dma_fence_put(fences[i]); Which means for the failing 'i' the dma_fence_put was already a double free. Possibly there were no users at that time, or the test cases were insufficient to hit it. The bug was then only noticed and fixed after commit 9c2ba265352a ("drm/scheduler: use new iterator in drm_sched_job_add_implicit_dependencies v2") landed, with its fixup of commit 4eaf02d6076c ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies"). At that point it was a slightly different flavour of a double free, which commit 963d0b356935 ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies harder") noticed and attempted to fix. But it only moved the double free from happening inside the drm_sched_job_add_dependency(), when releasing the reference not yet obtained, to the caller, when releasing the reference already released by the former in the failure case. As such it is not easy to identify the right target for the fixes tag so lets keep it simple and just continue the chain. While fixing we also improve the comment and explain the reason for taking the reference and not dropping it. Signed-off-by: Tvrtko Ursulin Fixes: 963d0b356935 ("drm/scheduler: fix drm_sched_job_add_implicit_dependencies harder") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/dri-devel/aNFbXq8OeYl3QSdm@stanley.mountain/ Cc: Christian König Cc: Rob Clark Cc: Daniel Vetter Cc: Matthew Brost Cc: Danilo Krummrich Cc: Philipp Stanner Cc: Christian König Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Philipp Stanner Link: https://lore.kernel.org/r/20251015084015.6273-1-tvrtko.ursulin@igalia.com (cherry picked from commit 5801e65206b065b0b2af032f7f1eef222aa2fd83) Signed-off-by: Brett Mastbergen --- drivers/gpu/drm/scheduler/sched_main.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 5a3a622fc672f..ebe1724ea8011 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -775,13 +775,14 @@ int drm_sched_job_add_resv_dependencies(struct drm_sched_job *job, dma_resv_assert_held(resv); dma_resv_for_each_fence(&cursor, resv, usage, fence) { - /* Make sure to grab an additional ref on the added fence */ - dma_fence_get(fence); - ret = drm_sched_job_add_dependency(job, fence); - if (ret) { - dma_fence_put(fence); + /* + * As drm_sched_job_add_dependency always consumes the fence + * reference (even when it fails), and dma_resv_for_each_fence + * is not obtaining one, we need to grab one before calling. + */ + ret = drm_sched_job_add_dependency(job, dma_fence_get(fence)); + if (ret) return ret; - } } return 0; } From 4a348f3f4ae417b9b1e8b264fd8a2eb4268cbf4c Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Wed, 11 Feb 2026 15:43:17 -0500 Subject: [PATCH 3/6] vsock: Ignore signal/timeout on connect() if already established jira VULN-160781 cve CVE-2025-40248 commit-author Michal Luczaj commit 002541ef650b742a198e4be363881439bb9d86b4 During connect(), acting on a signal/timeout by disconnecting an already established socket leads to several issues: 1. connect() invoking vsock_transport_cancel_pkt() -> virtio_transport_purge_skbs() may race with sendmsg() invoking virtio_transport_get_credit(). This results in a permanently elevated `vvs->bytes_unsent`. Which, in turn, confuses the SOCK_LINGER handling. 2. connect() resetting a connected socket's state may race with socket being placed in a sockmap. A disconnected socket remaining in a sockmap breaks sockmap's assumptions. And gives rise to WARNs. 3. connect() transitioning SS_CONNECTED -> SS_UNCONNECTED allows for a transport change/drop after TCP_ESTABLISHED. Which poses a problem for any simultaneous sendmsg() or connect() and may result in a use-after-free/null-ptr-deref. Do not disconnect socket on signal/timeout. Keep the logic for unconnected sockets: they don't linger, can't be placed in a sockmap, are rejected by sendmsg(). [1]: https://lore.kernel.org/netdev/e07fd95c-9a38-4eea-9638-133e38c2ec9b@rbox.co/ [2]: https://lore.kernel.org/netdev/20250317-vsock-trans-signal-race-v4-0-fc8837f3f1d4@rbox.co/ [3]: https://lore.kernel.org/netdev/60f1b7db-3099-4f6a-875e-af9f6ef194f6@rbox.co/ Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Signed-off-by: Michal Luczaj Reviewed-by: Stefano Garzarella Link: https://patch.msgid.link/20251119-vsock-interrupted-connect-v2-1-70734cf1233f@rbox.co Signed-off-by: Jakub Kicinski (cherry picked from commit 002541ef650b742a198e4be363881439bb9d86b4) Signed-off-by: Brett Mastbergen --- net/vmw_vsock/af_vsock.c | 40 +++++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 9 deletions(-) diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index d19538b97489d..0320729217844 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1507,18 +1507,40 @@ static int vsock_connect(struct socket *sock, struct sockaddr *addr, timeout = schedule_timeout(timeout); lock_sock(sk); - if (signal_pending(current)) { - err = sock_intr_errno(timeout); - sk->sk_state = sk->sk_state == TCP_ESTABLISHED ? TCP_CLOSING : TCP_CLOSE; - sock->state = SS_UNCONNECTED; - vsock_transport_cancel_pkt(vsk); - vsock_remove_connected(vsk); - goto out_wait; - } else if ((sk->sk_state != TCP_ESTABLISHED) && (timeout == 0)) { - err = -ETIMEDOUT; + /* Connection established. Whatever happens to socket once we + * release it, that's not connect()'s concern. No need to go + * into signal and timeout handling. Call it a day. + * + * Note that allowing to "reset" an already established socket + * here is racy and insecure. + */ + if (sk->sk_state == TCP_ESTABLISHED) + break; + + /* If connection was _not_ established and a signal/timeout came + * to be, we want the socket's state reset. User space may want + * to retry. + * + * sk_state != TCP_ESTABLISHED implies that socket is not on + * vsock_connected_table. We keep the binding and the transport + * assigned. + */ + if (signal_pending(current) || timeout == 0) { + err = timeout == 0 ? -ETIMEDOUT : sock_intr_errno(timeout); + + /* Listener might have already responded with + * VIRTIO_VSOCK_OP_RESPONSE. Its handling expects our + * sk_state == TCP_SYN_SENT, which hereby we break. + * In such case VIRTIO_VSOCK_OP_RST will follow. + */ sk->sk_state = TCP_CLOSE; sock->state = SS_UNCONNECTED; + + /* Try to cancel VIRTIO_VSOCK_OP_REQUEST skb sent out by + * transport->connect(). + */ vsock_transport_cancel_pkt(vsk); + goto out_wait; } From 562ed1b2d1cbd3a520bcf0aca190ae7906ef5bb3 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Wed, 11 Feb 2026 15:44:07 -0500 Subject: [PATCH 4/6] mptcp: fix race condition in mptcp_schedule_work() jira VULN-160809 cve CVE-2025-40258 commit-author Eric Dumazet commit 035bca3f017ee9dea3a5a756e77a6f7138cc6eea syzbot reported use-after-free in mptcp_schedule_work() [1] Issue here is that mptcp_schedule_work() schedules a work, then gets a refcount on sk->sk_refcnt if the work was scheduled. This refcount will be released by mptcp_worker(). [A] if (schedule_work(...)) { [B] sock_hold(sk); return true; } Problem is that mptcp_worker() can run immediately and complete before [B] We need instead : sock_hold(sk); if (schedule_work(...)) return true; sock_put(sk); [1] refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 29 at lib/refcount.c:25 refcount_warn_saturate+0xfa/0x1d0 lib/refcount.c:25 Call Trace: __refcount_add include/linux/refcount.h:-1 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] sock_hold include/net/sock.h:816 [inline] mptcp_schedule_work+0x164/0x1a0 net/mptcp/protocol.c:943 mptcp_tout_timer+0x21/0xa0 net/mptcp/protocol.c:2316 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x648/0x970 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403 handle_softirqs+0x22f/0x710 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] run_ktimerd+0xcf/0x190 kernel/softirq.c:1138 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Cc: stable@vger.kernel.org Fixes: 3b1d6210a957 ("mptcp: implement and use MPTCP-level retransmission") Reported-by: syzbot+355158e7e301548a1424@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6915b46f.050a0220.3565dc.0028.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Reviewed-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20251113103924.3737425-1-edumazet@google.com Signed-off-by: Jakub Kicinski (cherry picked from commit 035bca3f017ee9dea3a5a756e77a6f7138cc6eea) Signed-off-by: Brett Mastbergen --- net/mptcp/protocol.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index d24afb0715ddd..414a8775af6b6 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -930,14 +930,19 @@ static void mptcp_reset_rtx_timer(struct sock *sk) bool mptcp_schedule_work(struct sock *sk) { - if (inet_sk_state_load(sk) != TCP_CLOSE && - schedule_work(&mptcp_sk(sk)->work)) { - /* each subflow already holds a reference to the sk, and the - * workqueue is invoked by a subflow, so sk can't go away here. - */ - sock_hold(sk); + if (inet_sk_state_load(sk) == TCP_CLOSE) + return false; + + /* Get a reference on this socket, mptcp_worker() will release it. + * As mptcp_worker() might complete before us, we can not avoid + * a sock_hold()/sock_put() if schedule_work() returns false. + */ + sock_hold(sk); + + if (schedule_work(&mptcp_sk(sk)->work)) return true; - } + + sock_put(sk); return false; } From b752a1a59a9bfa9d9e9446b378ee291aed55c202 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Wed, 11 Feb 2026 15:44:37 -0500 Subject: [PATCH 5/6] net: atlantic: fix fragment overflow handling in RX path jira VULN-170100 cve CVE-2025-68301 commit-author Jiefeng Zhang commit 5ffcb7b890f61541201461580bb6622ace405aec The atlantic driver can receive packets with more than MAX_SKB_FRAGS (17) fragments when handling large multi-descriptor packets. This causes an out-of-bounds write in skb_add_rx_frag_netmem() leading to kernel panic. The issue occurs because the driver doesn't check the total number of fragments before calling skb_add_rx_frag(). When a packet requires more than MAX_SKB_FRAGS fragments, the fragment index exceeds the array bounds. Fix by assuming there will be an extra frag if buff->len > AQ_CFG_RX_HDR_SIZE, then all fragments are accounted for. And reusing the existing check to prevent the overflow earlier in the code path. This crash occurred in production with an Aquantia AQC113 10G NIC. Stack trace from production environment: ``` RIP: 0010:skb_add_rx_frag_netmem+0x29/0xd0 Code: 90 f3 0f 1e fa 0f 1f 44 00 00 48 89 f8 41 89 ca 48 89 d7 48 63 ce 8b 90 c0 00 00 00 48 c1 e1 04 48 01 ca 48 03 90 c8 00 00 00 <48> 89 7a 30 44 89 52 3c 44 89 42 38 40 f6 c7 01 75 74 48 89 fa 83 RSP: 0018:ffffa9bec02a8d50 EFLAGS: 00010287 RAX: ffff925b22e80a00 RBX: ffff925ad38d2700 RCX: fffffffe0a0c8000 RDX: ffff9258ea95bac0 RSI: ffff925ae0a0c800 RDI: 0000000000037a40 RBP: 0000000000000024 R08: 0000000000000000 R09: 0000000000000021 R10: 0000000000000848 R11: 0000000000000000 R12: ffffa9bec02a8e24 R13: ffff925ad8615570 R14: 0000000000000000 R15: ffff925b22e80a00 FS: 0000000000000000(0000) GS:ffff925e47880000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff9258ea95baf0 CR3: 0000000166022004 CR4: 0000000000f72ef0 PKRU: 55555554 Call Trace: aq_ring_rx_clean+0x175/0xe60 [atlantic] ? aq_ring_rx_clean+0x14d/0xe60 [atlantic] ? aq_ring_tx_clean+0xdf/0x190 [atlantic] ? kmem_cache_free+0x348/0x450 ? aq_vec_poll+0x81/0x1d0 [atlantic] ? __napi_poll+0x28/0x1c0 ? net_rx_action+0x337/0x420 ``` Fixes: 6aecbba12b5c ("net: atlantic: add check for MAX_SKB_FRAGS") Changes in v4: - Add Fixes: tag to satisfy patch validation requirements. Changes in v3: - Fix by assuming there will be an extra frag if buff->len > AQ_CFG_RX_HDR_SIZE, then all fragments are accounted for. Signed-off-by: Jiefeng Zhang Link: https://patch.msgid.link/20251126032249.69358-1-jiefeng.z.zhang@gmail.com Signed-off-by: Jakub Kicinski (cherry picked from commit 5ffcb7b890f61541201461580bb6622ace405aec) Signed-off-by: Brett Mastbergen --- drivers/net/ethernet/aquantia/atlantic/aq_ring.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c index 4de22eed099a8..63d7280137ead 100644 --- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c +++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c @@ -576,6 +576,11 @@ static int __aq_ring_rx_clean(struct aq_ring_s *self, struct napi_struct *napi, if (!buff->is_eop) { unsigned int frag_cnt = 0U; + + /* There will be an extra fragment */ + if (buff->len > AQ_CFG_RX_HDR_SIZE) + frag_cnt++; + buff_ = buff; do { bool is_rsc_completed = true; From d46c14d79bd989d17c75d365d9eec9006eb7cc97 Mon Sep 17 00:00:00 2001 From: Brett Mastbergen Date: Thu, 12 Feb 2026 11:22:12 -0500 Subject: [PATCH 6/6] drm: Check output polling initialized before disabling jira VULN-37936 cve CVE-2024-35927 commit-author Shradha Gupta commit 5abffb66d12bcac84bf7b66389c571b8bb6e82bd In drm_kms_helper_poll_disable() check if output polling support is initialized before disabling polling. If not flag this as a warning. Additionally in drm_mode_config_helper_suspend() and drm_mode_config_helper_resume() calls, that re the callers of these functions, avoid invoking them if polling is not initialized. For drivers like hyperv-drm, that do not initialize connector polling, if suspend is called without this check, it leads to suspend failure with following stack [ 770.719392] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. [ 770.720592] printk: Suspending console(s) (use no_console_suspend to debug) [ 770.948823] ------------[ cut here ]------------ [ 770.948824] WARNING: CPU: 1 PID: 17197 at kernel/workqueue.c:3162 __flush_work.isra.0+0x212/0x230 [ 770.948831] Modules linked in: rfkill nft_counter xt_conntrack xt_owner udf nft_compat crc_itu_t nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink vfat fat mlx5_ib ib_uverbs ib_core mlx5_core intel_rapl_msr intel_rapl_common kvm_amd ccp mlxfw kvm psample hyperv_drm tls drm_shmem_helper drm_kms_helper irqbypass pcspkr syscopyarea sysfillrect sysimgblt hv_balloon hv_utils joydev drm fuse xfs libcrc32c pci_hyperv pci_hyperv_intf sr_mod sd_mod cdrom t10_pi sg hv_storvsc scsi_transport_fc hv_netvsc serio_raw hyperv_keyboard hid_hyperv crct10dif_pclmul crc32_pclmul crc32c_intel hv_vmbus ghash_clmulni_intel dm_mirror dm_region_hash dm_log dm_mod [ 770.948863] CPU: 1 PID: 17197 Comm: systemd-sleep Not tainted 5.14.0-362.2.1.el9_3.x86_64 #1 [ 770.948865] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 770.948866] RIP: 0010:__flush_work.isra.0+0x212/0x230 [ 770.948869] Code: 8b 4d 00 4c 8b 45 08 89 ca 48 c1 e9 04 83 e2 08 83 e1 0f 83 ca 02 89 c8 48 0f ba 6d 00 03 e9 25 ff ff ff 0f 0b e9 4e ff ff ff <0f> 0b 45 31 ed e9 44 ff ff ff e8 8f 89 b2 00 66 66 2e 0f 1f 84 00 [ 770.948870] RSP: 0018:ffffaf4ac213fb10 EFLAGS: 00010246 [ 770.948871] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8c992857 [ 770.948872] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff9aad82b00330 [ 770.948873] RBP: ffff9aad82b00330 R08: 0000000000000000 R09: ffff9aad87ee3d10 [ 770.948874] R10: 0000000000000200 R11: 0000000000000000 R12: ffff9aad82b00330 [ 770.948874] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 770.948875] FS: 00007ff1b2f6bb40(0000) GS:ffff9aaf37d00000(0000) knlGS:0000000000000000 [ 770.948878] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 770.948878] CR2: 0000555f345cb666 CR3: 00000001462dc005 CR4: 0000000000370ee0 [ 770.948879] Call Trace: [ 770.948880] [ 770.948881] ? show_trace_log_lvl+0x1c4/0x2df [ 770.948884] ? show_trace_log_lvl+0x1c4/0x2df [ 770.948886] ? __cancel_work_timer+0x103/0x190 [ 770.948887] ? __flush_work.isra.0+0x212/0x230 [ 770.948889] ? __warn+0x81/0x110 [ 770.948891] ? __flush_work.isra.0+0x212/0x230 [ 770.948892] ? report_bug+0x10a/0x140 [ 770.948895] ? handle_bug+0x3c/0x70 [ 770.948898] ? exc_invalid_op+0x14/0x70 [ 770.948899] ? asm_exc_invalid_op+0x16/0x20 [ 770.948903] ? __flush_work.isra.0+0x212/0x230 [ 770.948905] __cancel_work_timer+0x103/0x190 [ 770.948907] ? _raw_spin_unlock_irqrestore+0xa/0x30 [ 770.948910] drm_kms_helper_poll_disable+0x1e/0x40 [drm_kms_helper] [ 770.948923] drm_mode_config_helper_suspend+0x1c/0x80 [drm_kms_helper] [ 770.948933] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus] [ 770.948942] hyperv_vmbus_suspend+0x17/0x40 [hyperv_drm] [ 770.948944] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus] [ 770.948951] dpm_run_callback+0x4c/0x140 [ 770.948954] __device_suspend_noirq+0x74/0x220 [ 770.948956] dpm_noirq_suspend_devices+0x148/0x2a0 [ 770.948958] dpm_suspend_end+0x54/0xe0 [ 770.948960] create_image+0x14/0x290 [ 770.948963] hibernation_snapshot+0xd6/0x200 [ 770.948964] hibernate.cold+0x8b/0x1fb [ 770.948967] state_store+0xcd/0xd0 [ 770.948969] kernfs_fop_write_iter+0x124/0x1b0 [ 770.948973] new_sync_write+0xff/0x190 [ 770.948976] vfs_write+0x1ef/0x280 [ 770.948978] ksys_write+0x5f/0xe0 [ 770.948979] do_syscall_64+0x5c/0x90 [ 770.948981] ? syscall_exit_work+0x103/0x130 [ 770.948983] ? syscall_exit_to_user_mode+0x12/0x30 [ 770.948985] ? do_syscall_64+0x69/0x90 [ 770.948986] ? do_syscall_64+0x69/0x90 [ 770.948987] ? do_user_addr_fault+0x1d6/0x6a0 [ 770.948989] ? do_syscall_64+0x69/0x90 [ 770.948990] ? exc_page_fault+0x62/0x150 [ 770.948992] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 770.948995] RIP: 0033:0x7ff1b293eba7 [ 770.949010] Code: 0b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 [ 770.949011] RSP: 002b:00007ffde3912128 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 770.949012] RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007ff1b293eba7 [ 770.949013] RDX: 0000000000000005 RSI: 00007ffde3912210 RDI: 0000000000000004 [ 770.949014] RBP: 00007ffde3912210 R08: 000055d7dd4c9510 R09: 00007ff1b29b14e0 [ 770.949014] R10: 00007ff1b29b13e0 R11: 0000000000000246 R12: 0000000000000005 [ 770.949015] R13: 000055d7dd4c53e0 R14: 0000000000000005 R15: 00007ff1b29f69e0 [ 770.949016] [ 770.949017] ---[ end trace e6fa0618bfa2f31d ]--- Built-on: Rhel9, Ubuntu22 Signed-off-by: Shradha Gupta Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/1706856208-9617-1-git-send-email-shradhagupta@linux.microsoft.com (cherry picked from commit 5abffb66d12bcac84bf7b66389c571b8bb6e82bd) Signed-off-by: Brett Mastbergen --- drivers/gpu/drm/drm_modeset_helper.c | 19 ++++++++++++++++--- drivers/gpu/drm/drm_probe_helper.c | 13 +++++++++++-- 2 files changed, 27 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/drm_modeset_helper.c b/drivers/gpu/drm/drm_modeset_helper.c index f858dfedf2cfc..2c582020cb423 100644 --- a/drivers/gpu/drm/drm_modeset_helper.c +++ b/drivers/gpu/drm/drm_modeset_helper.c @@ -193,13 +193,22 @@ int drm_mode_config_helper_suspend(struct drm_device *dev) if (!dev) return 0; + /* + * Don't disable polling if it was never initialized + */ + if (dev->mode_config.poll_enabled) + drm_kms_helper_poll_disable(dev); - drm_kms_helper_poll_disable(dev); drm_fb_helper_set_suspend_unlocked(dev->fb_helper, 1); state = drm_atomic_helper_suspend(dev); if (IS_ERR(state)) { drm_fb_helper_set_suspend_unlocked(dev->fb_helper, 0); - drm_kms_helper_poll_enable(dev); + /* + * Don't enable polling if it was never initialized + */ + if (dev->mode_config.poll_enabled) + drm_kms_helper_poll_enable(dev); + return PTR_ERR(state); } @@ -239,7 +248,11 @@ int drm_mode_config_helper_resume(struct drm_device *dev) dev->mode_config.suspend_state = NULL; drm_fb_helper_set_suspend_unlocked(dev->fb_helper, 0); - drm_kms_helper_poll_enable(dev); + /* + * Don't enable polling if it is not initialized + */ + if (dev->mode_config.poll_enabled) + drm_kms_helper_poll_enable(dev); return ret; } diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index 3f479483d7d80..bd76603dc3876 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -293,14 +293,17 @@ static void reschedule_output_poll_work(struct drm_device *dev) * Drivers can call this helper from their device resume implementation. It is * not an error to call this even when output polling isn't enabled. * + * If device polling was never initialized before, this call will trigger a + * warning and return. + * * Note that calls to enable and disable polling must be strictly ordered, which * is automatically the case when they're only call from suspend/resume * callbacks. */ void drm_kms_helper_poll_enable(struct drm_device *dev) { - if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll || - dev->mode_config.poll_running) + if (drm_WARN_ON_ONCE(dev, !dev->mode_config.poll_enabled) || + !drm_kms_helper_poll || dev->mode_config.poll_running) return; if (drm_kms_helper_enable_hpd(dev) || @@ -871,12 +874,18 @@ EXPORT_SYMBOL(drm_kms_helper_is_poll_worker); * not an error to call this even when output polling isn't enabled or already * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable(). * + * If however, the polling was never initialized, this call will trigger a + * warning and return + * * Note that calls to enable and disable polling must be strictly ordered, which * is automatically the case when they're only call from suspend/resume * callbacks. */ void drm_kms_helper_poll_disable(struct drm_device *dev) { + if (drm_WARN_ON(dev, !dev->mode_config.poll_enabled)) + return; + if (dev->mode_config.poll_running) drm_kms_helper_disable_hpd(dev);