In the Linux kernel, the following vulnerability has been resolved: cxl/region: Avoid null pointer dereference in region lookup cxl_dpa_to_region() looks up a region based on a memdev and DPA. It wrongly assumes an endpoint found mapping the DPA is also of a fully assembled region. When not true it leads to a null pointer dereference looking up the region name. This appears during testing of region lookup after a failure to assemble a BIOS defined region or if the lookup raced with the assembly of the BIOS defined region. Failure to clean up BIOS defined regions that fail assembly is an issue in itself and a fix to that problem will alleviate some of the impact. It will not alleviate the race condition so let's harden this path. The behavior change is that the kernel oops due to a null pointer dereference is replaced with a dev_dbg() message noting that an endpoint was mapped. Additional comments are added so that future users of this function can more clearly understand what it provides.

In the Linux kernel, the following vulnerability has been resolved: io_uring: check for non-NULL file pointer in io_file_can_poll() In earlier kernels, it was possible to trigger a NULL pointer dereference off the forced async preparation path, if no file had been assigned. The trace leading to that looks as follows: BUG: kernel NULL pointer dereference, address: 00000000000000b0 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 67 PID: 1633 Comm: buf-ring-invali Not tainted 6.8.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 2/2/2022 RIP: 0010:io_buffer_select+0xc3/0x210 Code: 00 00 48 39 d1 0f 82 ae 00 00 00 48 81 4b 48 00 00 01 00 48 89 73 70 0f b7 50 0c 66 89 53 42 85 ed 0f 85 d2 00 00 00 48 8b 13 <48> 8b 92 b0 00 00 00 48 83 7a 40 00 0f 84 21 01 00 00 4c 8b 20 5b RSP: 0018:ffffb7bec38c7d88 EFLAGS: 00010246 RAX: ffff97af2be61000 RBX: ffff97af234f1700 RCX: 0000000000000040 RDX: 0000000000000000 RSI: ffff97aecfb04820 RDI: ffff97af234f1700 RBP: 0000000000000000 R08: 0000000000200030 R09: 0000000000000020 R10: ffffb7bec38c7dc8 R11: 000000000000c000 R12: ffffb7bec38c7db8 R13: ffff97aecfb05800 R14: ffff97aecfb05800 R15: ffff97af2be5e000 FS: 00007f852f74b740(0000) GS:ffff97b1eeec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000b0 CR3: 000000016deab005 CR4: 0000000000370ef0 Call Trace: <TASK> ? __die+0x1f/0x60 ? page_fault_oops+0x14d/0x420 ? do_user_addr_fault+0x61/0x6a0 ? exc_page_fault+0x6c/0x150 ? asm_exc_page_fault+0x22/0x30 ? io_buffer_select+0xc3/0x210 __io_import_iovec+0xb5/0x120 io_readv_prep_async+0x36/0x70 io_queue_sqe_fallback+0x20/0x260 io_submit_sqes+0x314/0x630 __do_sys_io_uring_enter+0x339/0xbc0 ? __do_sys_io_uring_register+0x11b/0xc50 ? vm_mmap_pgoff+0xce/0x160 do_syscall_64+0x5f/0x180 entry_SYSCALL_64_after_hwframe+0x46/0x4e RIP: 0033:0x55e0a110a67e Code: ba cc 00 00 00 45 31 c0 44 0f b6 92 d0 00 00 00 31 d2 41 b9 08 00 00 00 41 83 e2 01 41 c1 e2 04 41 09 c2 b8 aa 01 00 00 0f 05 <c3> 90 89 30 eb a9 0f 1f 40 00 48 8b 42 20 8b 00 a8 06 75 af 85 f6 because the request is marked forced ASYNC and has a bad file fd, and hence takes the forced async prep path. Current kernels with the request async prep cleaned up can no longer hit this issue, but for ease of backporting, let's add this safety check in here too as it really doesn't hurt. For both cases, this will inevitably end with a CQE posted with -EBADF.

In the Linux kernel, the following vulnerability has been resolved: drm: bridge: cdns-mhdp8546: Fix possible null pointer dereference In cdns_mhdp_atomic_enable(), the return value of drm_mode_duplicate() is assigned to mhdp_state->current_mode, and there is a dereference of it in drm_mode_set_name(), which will lead to a NULL pointer dereference on failure of drm_mode_duplicate(). Fix this bug add a check of mhdp_state->current_mode.

In the Linux kernel, the following vulnerability has been resolved: eventfs: Fix a possible null pointer dereference in eventfs_find_events() In function eventfs_find_events,there is a potential null pointer that may be caused by calling update_events_attr which will perform some operations on the members of the ei struct when ei is NULL. Hence,When ei->is_freed is set,return NULL directly.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix netif state handling mlx5e_suspend cleans resources only if netif_device_present() returns true. However, mlx5e_resume changes the state of netif, via mlx5e_nic_enable, only if reg_state == NETREG_REGISTERED. In the below case, the above leads to NULL-ptr Oops[1] and memory leaks: mlx5e_probe _mlx5e_resume mlx5e_attach_netdev mlx5e_nic_enable <-- netdev not reg, not calling netif_device_attach() register_netdev <-- failed for some reason. ERROR_FLOW: _mlx5e_suspend <-- netif_device_present return false, resources aren't freed :( Hence, clean resources in this case as well. [1] BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0010 [#1] SMP CPU: 2 PID: 9345 Comm: test-ovs-ct-gen Not tainted 6.5.0_for_upstream_min_debug_2023_09_05_16_01 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at0xffffffffffffffd6. RSP: 0018:ffff888178aaf758 EFLAGS: 00010246 Call Trace: <TASK> ? __die+0x20/0x60 ? page_fault_oops+0x14c/0x3c0 ? exc_page_fault+0x75/0x140 ? asm_exc_page_fault+0x22/0x30 notifier_call_chain+0x35/0xb0 blocking_notifier_call_chain+0x3d/0x60 mlx5_blocking_notifier_call_chain+0x22/0x30 [mlx5_core] mlx5_core_uplink_netdev_event_replay+0x3e/0x60 [mlx5_core] mlx5_mdev_netdev_track+0x53/0x60 [mlx5_ib] mlx5_ib_roce_init+0xc3/0x340 [mlx5_ib] __mlx5_ib_add+0x34/0xd0 [mlx5_ib] mlx5r_probe+0xe1/0x210 [mlx5_ib] ? auxiliary_match_id+0x6a/0x90 auxiliary_bus_probe+0x38/0x80 ? driver_sysfs_add+0x51/0x80 really_probe+0xc9/0x3e0 ? driver_probe_device+0x90/0x90 __driver_probe_device+0x80/0x160 driver_probe_device+0x1e/0x90 __device_attach_driver+0x7d/0x100 bus_for_each_drv+0x80/0xd0 __device_attach+0xbc/0x1f0 bus_probe_device+0x86/0xa0 device_add+0x637/0x840 __auxiliary_device_add+0x3b/0xa0 add_adev+0xc9/0x140 [mlx5_core] mlx5_rescan_drivers_locked+0x22a/0x310 [mlx5_core] mlx5_register_device+0x53/0xa0 [mlx5_core] mlx5_init_one_devl_locked+0x5c4/0x9c0 [mlx5_core] mlx5_init_one+0x3b/0x60 [mlx5_core] probe_one+0x44c/0x730 [mlx5_core] local_pci_probe+0x3e/0x90 pci_device_probe+0xbf/0x210 ? kernfs_create_link+0x5d/0xa0 ? sysfs_do_create_link_sd+0x60/0xc0 really_probe+0xc9/0x3e0 ? driver_probe_device+0x90/0x90 __driver_probe_device+0x80/0x160 driver_probe_device+0x1e/0x90 __device_attach_driver+0x7d/0x100 bus_for_each_drv+0x80/0xd0 __device_attach+0xbc/0x1f0 pci_bus_add_device+0x54/0x80 pci_iov_add_virtfn+0x2e6/0x320 sriov_enable+0x208/0x420 mlx5_core_sriov_configure+0x9e/0x200 [mlx5_core] sriov_numvfs_store+0xae/0x1a0 kernfs_fop_write_iter+0x10c/0x1a0 vfs_write+0x291/0x3c0 ksys_write+0x5f/0xe0 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x46/0xb0 CR2: 0000000000000000 ---[ end trace 0000000000000000 ]---

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add callback function pointer check before its call In dpu_core_irq_callback_handler() callback function pointer is compared to NULL, but then callback function is unconditionally called by this pointer. Fix this bug by adding conditional return. Found by Linux Verification Center (linuxtesting.org) with SVACE. Patchwork: https://patchwork.freedesktop.org/patch/588237/

In the Linux kernel, the following vulnerability has been resolved: cpufreq: exit() callback is optional The exit() callback is optional and shouldn't be called without checking a valid pointer first. Also, we must clear freq_table pointer even if the exit() callback isn't present.

A null pointer dereference vulnerability was found in nft_dynset_init() in net/netfilter/nft_dynset.c in nf_tables in the Linux kernel. This issue may allow a local attacker with CAP_NET_ADMIN user privilege to trigger a denial of service.

A null pointer dereference vulnerability was found in ath10k_wmi_tlv_op_pull_mgmt_tx_compl_ev() in drivers/net/wireless/ath/ath10k/wmi-tlv.c in the Linux kernel. This issue could be exploited to trigger a denial of service.

In the Linux kernel, the following vulnerability has been resolved: net: sock: fix hardened usercopy panic in sock_recv_errqueue skbuff_fclone_cache was created without defining a usercopy region, [1] unlike skbuff_head_cache which properly whitelists the cb[] field. [2] This causes a usercopy BUG() when CONFIG_HARDENED_USERCOPY is enabled and the kernel attempts to copy sk_buff.cb data to userspace via sock_recv_errqueue() -> put_cmsg(). The crash occurs when: 1. TCP allocates an skb using alloc_skb_fclone() (from skbuff_fclone_cache) [1] 2. The skb is cloned via skb_clone() using the pre-allocated fclone [3] 3. The cloned skb is queued to sk_error_queue for timestamp reporting 4. Userspace reads the error queue via recvmsg(MSG_ERRQUEUE) 5. sock_recv_errqueue() calls put_cmsg() to copy serr->ee from skb->cb [4] 6. __check_heap_object() fails because skbuff_fclone_cache has no usercopy whitelist [5] When cloned skbs allocated from skbuff_fclone_cache are used in the socket error queue, accessing the sock_exterr_skb structure in skb->cb via put_cmsg() triggers a usercopy hardening violation: [ 5.379589] usercopy: Kernel memory exposure attempt detected from SLUB object 'skbuff_fclone_cache' (offset 296, size 16)! [ 5.382796] kernel BUG at mm/usercopy.c:102! [ 5.383923] Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI [ 5.384903] CPU: 1 UID: 0 PID: 138 Comm: poc_put_cmsg Not tainted 6.12.57 #7 [ 5.384903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 5.384903] RIP: 0010:usercopy_abort+0x6c/0x80 [ 5.384903] Code: 1a 86 51 48 c7 c2 40 15 1a 86 41 52 48 c7 c7 c0 15 1a 86 48 0f 45 d6 48 c7 c6 80 15 1a 86 48 89 c1 49 0f 45 f3 e8 84 27 88 ff <0f> 0b 490 [ 5.384903] RSP: 0018:ffffc900006f77a8 EFLAGS: 00010246 [ 5.384903] RAX: 000000000000006f RBX: ffff88800f0ad2a8 RCX: 1ffffffff0f72e74 [ 5.384903] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff87b973a0 [ 5.384903] RBP: 0000000000000010 R08: 0000000000000000 R09: fffffbfff0f72e74 [ 5.384903] R10: 0000000000000003 R11: 79706f6372657375 R12: 0000000000000001 [ 5.384903] R13: ffff88800f0ad2b8 R14: ffffea00003c2b40 R15: ffffea00003c2b00 [ 5.384903] FS: 0000000011bc4380(0000) GS:ffff8880bf100000(0000) knlGS:0000000000000000 [ 5.384903] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5.384903] CR2: 000056aa3b8e5fe4 CR3: 000000000ea26004 CR4: 0000000000770ef0 [ 5.384903] PKRU: 55555554 [ 5.384903] Call Trace: [ 5.384903] <TASK> [ 5.384903] __check_heap_object+0x9a/0xd0 [ 5.384903] __check_object_size+0x46c/0x690 [ 5.384903] put_cmsg+0x129/0x5e0 [ 5.384903] sock_recv_errqueue+0x22f/0x380 [ 5.384903] tls_sw_recvmsg+0x7ed/0x1960 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5.384903] ? schedule+0x6d/0x270 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5.384903] ? mutex_unlock+0x81/0xd0 [ 5.384903] ? __pfx_mutex_unlock+0x10/0x10 [ 5.384903] ? __pfx_tls_sw_recvmsg+0x10/0x10 [ 5.384903] ? _raw_spin_lock_irqsave+0x8f/0xf0 [ 5.384903] ? _raw_read_unlock_irqrestore+0x20/0x40 [ 5.384903] ? srso_alias_return_thunk+0x5/0xfbef5 The crash offset 296 corresponds to skb2->cb within skbuff_fclones: - sizeof(struct sk_buff) = 232 - offsetof(struct sk_buff, cb) = 40 - offset of skb2.cb in fclones = 232 + 40 = 272 - crash offset 296 = 272 + 24 (inside sock_exterr_skb.ee) This patch uses a local stack variable as a bounce buffer to avoid the hardened usercopy check failure. [1] https://elixir.bootlin.com/linux/v6.12.62/source/net/ipv4/tcp.c#L885 [2] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5104 [3] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5566 [4] https://elixir.bootlin.com/linux/v6.12.62/source/net/core/skbuff.c#L5491 [5] https://elixir.bootlin.com/linux/v6.12.62/source/mm/slub.c#L5719

In the Linux kernel, the following vulnerability has been resolved: sctp: check send stream number after wait_for_sndbuf This patch fixes a corner case where the asoc out stream count may change after wait_for_sndbuf. When the main thread in the client starts a connection, if its out stream count is set to N while the in stream count in the server is set to N - 2, another thread in the client keeps sending the msgs with stream number N - 1, and waits for sndbuf before processing INIT_ACK. However, after processing INIT_ACK, the out stream count in the client is shrunk to N - 2, the same to the in stream count in the server. The crash occurs when the thread waiting for sndbuf is awake and sends the msg in a non-existing stream(N - 1), the call trace is as below: KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] Call Trace: <TASK> sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170 sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163 sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868 sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 The fix is to add an unlikely check for the send stream number after the thread wakes up from the wait_for_sndbuf.

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Fix potential NULL pointer dereference Klocwork tool reported 'cur_dsd' may be dereferenced. Add fix to validate pointer before dereferencing the pointer.

In the Linux kernel, the following vulnerability has been resolved: spi: bcm-qspi: return error if neither hif_mspi nor mspi is available If neither a "hif_mspi" nor "mspi" resource is present, the driver will just early exit in probe but still return success. Apart from not doing anything meaningful, this would then also lead to a null pointer access on removal, as platform_get_drvdata() would return NULL, which it would then try to dereference when trying to unregister the spi master. Fix this by unconditionally calling devm_ioremap_resource(), as it can handle a NULL res and will then return a viable ERR_PTR() if we get one. The "return 0;" was previously a "goto qspi_resource_err;" where then ret was returned, but since ret was still initialized to 0 at this place this was a valid conversion in 63c5395bb7a9 ("spi: bcm-qspi: Fix use-after-free on unbind"). The issue was not introduced by this commit, only made more obvious.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Add null pointer check in gserial_resume Consider a case where gserial_disconnect has already cleared gser->ioport. And if a wakeup interrupt triggers afterwards, gserial_resume gets called, which will lead to accessing of gser->ioport and thus causing null pointer dereference.Add a null pointer check to prevent this. Added a static spinlock to prevent gser->ioport from becoming null after the newly added check.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_serial: Add null pointer check in gserial_suspend Consider a case where gserial_disconnect has already cleared gser->ioport. And if gserial_suspend gets called afterwards, it will lead to accessing of gser->ioport and thus causing null pointer dereference. Avoid this by adding a null pointer check. Added a static spinlock to prevent gser->ioport from becoming null after the newly added null pointer check.

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: do not run mt76_unregister_device() on unregistered hw Trying to probe a mt7921e pci card without firmware results in a successful probe where ieee80211_register_hw hasn't been called. When removing the driver, ieee802111_unregister_hw is called unconditionally leading to a kernel NULL pointer dereference. Fix the issue running mt76_unregister_device routine just for registered hw.

In the Linux kernel, the following vulnerability has been resolved: net/handshake: fix null-ptr-deref in handshake_nl_done_doit() We should not call trace_handshake_cmd_done_err() if socket lookup has failed. Also we should call trace_handshake_cmd_done_err() before releasing the file, otherwise dereferencing sock->sk can return garbage. This also reverts 7afc6d0a107f ("net/handshake: Fix uninitialized local variable") Unable to handle kernel paging request at virtual address dfff800000000003 KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [dfff800000000003] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 5986 Comm: syz-executor292 Not tainted 6.5.0-rc7-syzkaller-gfe4469582053 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : handshake_nl_done_doit+0x198/0x9c8 net/handshake/netlink.c:193 lr : handshake_nl_done_doit+0x180/0x9c8 sp : ffff800096e37180 x29: ffff800096e37200 x28: 1ffff00012dc6e34 x27: dfff800000000000 x26: ffff800096e373d0 x25: 0000000000000000 x24: 00000000ffffffa8 x23: ffff800096e373f0 x22: 1ffff00012dc6e38 x21: 0000000000000000 x20: ffff800096e371c0 x19: 0000000000000018 x18: 0000000000000000 x17: 0000000000000000 x16: ffff800080516cc4 x15: 0000000000000001 x14: 1fffe0001b14aa3b x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000003 x8 : 0000000000000003 x7 : ffff800080afe47c x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800080a88078 x2 : 0000000000000001 x1 : 00000000ffffffa8 x0 : 0000000000000000 Call trace: handshake_nl_done_doit+0x198/0x9c8 net/handshake/netlink.c:193 genl_family_rcv_msg_doit net/netlink/genetlink.c:970 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1050 [inline] genl_rcv_msg+0x96c/0xc50 net/netlink/genetlink.c:1067 netlink_rcv_skb+0x214/0x3c4 net/netlink/af_netlink.c:2549 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1078 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg net/socket.c:748 [inline] ____sys_sendmsg+0x56c/0x840 net/socket.c:2494 ___sys_sendmsg net/socket.c:2548 [inline] __sys_sendmsg+0x26c/0x33c net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2584 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 Code: 12800108 b90043e8 910062b3 d343fe68 (387b6908)

In the Linux kernel, the following vulnerability has been resolved: iw_cxgb4: Fix potential NULL dereference in c4iw_fill_res_cm_id_entry() This condition needs to match the previous "if (epcp->state == LISTEN) {" exactly to avoid a NULL dereference of either "listen_ep" or "ep". The problem is that "epcp" has been re-assigned so just testing "if (epcp->state == LISTEN) {" a second time is not sufficient.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix potential null dereference The adev->dm.dc pointer can be NULL and dereferenced in amdgpu_dm_fini() without checking. Add a NULL pointer check before calling dc_dmub_srv_destroy(). Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid() r5l_flush_stripe_to_raid() will check if the list 'flushing_ios' is empty, and then submit 'flush_bio', however, r5l_log_flush_endio() is clearing the list first and then clear the bio, which will cause null-ptr-deref: T1: submit flush io raid5d handle_active_stripes r5l_flush_stripe_to_raid // list is empty // add 'io_end_ios' to the list bio_init submit_bio // io1 T2: io1 is done r5l_log_flush_endio list_splice_tail_init // clear the list T3: submit new flush io ... r5l_flush_stripe_to_raid // list is empty // add 'io_end_ios' to the list bio_init bio_uninit // clear bio->bi_blkg submit_bio // null-ptr-deref Fix this problem by clearing bio before clearing the list in r5l_log_flush_endio().

In the Linux kernel, the following vulnerability has been resolved: ionic: catch failure from devlink_alloc Add a check for NULL on the alloc return. If devlink_alloc() fails and we try to use devlink_priv() on the NULL return, the kernel gets very unhappy and panics. With this fix, the driver load will still fail, but at least it won't panic the kernel.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/mdp5: Add check for kzalloc As kzalloc may fail and return NULL pointer, it should be better to check the return value in order to avoid the NULL pointer dereference. Patchwork: https://patchwork.freedesktop.org/patch/514154/

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Avoid fcport pointer dereference Klocwork reported warning of NULL pointer may be dereferenced. The routine exits when sa_ctl is NULL and fcport is allocated after the exit call thus causing NULL fcport pointer to dereference at the time of exit. To avoid fcport pointer dereference, exit the routine when sa_ctl is NULL.

In the Linux kernel, the following vulnerability has been resolved: RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish() If get_ep_from_tid() fails to lookup non-NULL value for ep, ep is dereferenced later regardless of whether it is empty. This patch adds a simple sanity check to fix the issue. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: kobject: Add sanity check for kset->kobj.ktype in kset_register() When I register a kset in the following way: static struct kset my_kset; kobject_set_name(&my_kset.kobj, "my_kset"); ret = kset_register(&my_kset); A null pointer dereference exception is occurred: [ 4453.568337] Unable to handle kernel NULL pointer dereference at \ virtual address 0000000000000028 ... ... [ 4453.810361] Call trace: [ 4453.813062] kobject_get_ownership+0xc/0x34 [ 4453.817493] kobject_add_internal+0x98/0x274 [ 4453.822005] kset_register+0x5c/0xb4 [ 4453.825820] my_kobj_init+0x44/0x1000 [my_kset] ... ... Because I didn't initialize my_kset.kobj.ktype. According to the description in Documentation/core-api/kobject.rst: - A ktype is the type of object that embeds a kobject. Every structure that embeds a kobject needs a corresponding ktype. So add sanity check to make sure kset->kobj.ktype is not NULL.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwl4965: Add missing check for create_singlethread_workqueue() Add the check for the return value of the create_singlethread_workqueue() in order to avoid NULL pointer dereference.

In the Linux kernel, the following vulnerability has been resolved: genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask() If ipi_send_{mask|single}() is called with an invalid interrupt number, all the local variables there will be NULL. ipi_send_verify() which is invoked from these functions does verify its 'data' parameter, resulting in a kernel oops in irq_data_get_affinity_mask() as the passed NULL pointer gets dereferenced. Add a missing NULL pointer check in ipi_send_verify()... Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool.

In the Linux kernel, the following vulnerability has been resolved: regulator: da9063: better fix null deref with partial DT Two versions of the original patch were sent but V1 was merged instead of V2 due to a mistake. So update to V2. The advantage of V2 is that it completely avoids dereferencing the pointer, even just to take the address, which may fix problems with some compilers. Both versions work on my gcc 9.4 but use the safer one.

In the Linux kernel, the following vulnerability has been resolved: bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent In some specific situations, the return value of __bch_btree_node_alloc may be NULL. This may lead to a potential NULL pointer dereference in caller function like a calling chain : btree_split->bch_btree_node_alloc->__bch_btree_node_alloc. Fix it by initializing the return value in __bch_btree_node_alloc.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix NULL pointer dereference in smb2_get_info_filesystem() If share is , share->path is NULL and it cause NULL pointer dereference issue.

In the Linux kernel, the following vulnerability has been resolved: ice: xsk: disable txq irq before flushing hw ice_qp_dis() intends to stop a given queue pair that is a target of xsk pool attach/detach. One of the steps is to disable interrupts on these queues. It currently is broken in a way that txq irq is turned off *after* HW flush which in turn takes no effect. ice_qp_dis(): -> ice_qvec_dis_irq() --> disable rxq irq --> flush hw -> ice_vsi_stop_tx_ring() -->disable txq irq Below splat can be triggered by following steps: - start xdpsock WITHOUT loading xdp prog - run xdp_rxq_info with XDP_TX action on this interface - start traffic - terminate xdpsock [ 256.312485] BUG: kernel NULL pointer dereference, address: 0000000000000018 [ 256.319560] #PF: supervisor read access in kernel mode [ 256.324775] #PF: error_code(0x0000) - not-present page [ 256.329994] PGD 0 P4D 0 [ 256.332574] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 256.337006] CPU: 3 PID: 32 Comm: ksoftirqd/3 Tainted: G OE 6.2.0-rc5+ #51 [ 256.345218] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019 [ 256.355807] RIP: 0010:ice_clean_rx_irq_zc+0x9c/0x7d0 [ice] [ 256.361423] Code: b7 8f 8a 00 00 00 66 39 ca 0f 84 f1 04 00 00 49 8b 47 40 4c 8b 24 d0 41 0f b7 45 04 66 25 ff 3f 66 89 04 24 0f 84 85 02 00 00 <49> 8b 44 24 18 0f b7 14 24 48 05 00 01 00 00 49 89 04 24 49 89 44 [ 256.380463] RSP: 0018:ffffc900088bfd20 EFLAGS: 00010206 [ 256.385765] RAX: 000000000000003c RBX: 0000000000000035 RCX: 000000000000067f [ 256.393012] RDX: 0000000000000775 RSI: 0000000000000000 RDI: ffff8881deb3ac80 [ 256.400256] RBP: 000000000000003c R08: ffff889847982710 R09: 0000000000010000 [ 256.407500] R10: ffffffff82c060c0 R11: 0000000000000004 R12: 0000000000000000 [ 256.414746] R13: ffff88811165eea0 R14: ffffc9000d255000 R15: ffff888119b37600 [ 256.421990] FS: 0000000000000000(0000) GS:ffff8897e0cc0000(0000) knlGS:0000000000000000 [ 256.430207] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 256.436036] CR2: 0000000000000018 CR3: 0000000005c0a006 CR4: 00000000007706e0 [ 256.443283] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 256.450527] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 256.457770] PKRU: 55555554 [ 256.460529] Call Trace: [ 256.463015] <TASK> [ 256.465157] ? ice_xmit_zc+0x6e/0x150 [ice] [ 256.469437] ice_napi_poll+0x46d/0x680 [ice] [ 256.473815] ? _raw_spin_unlock_irqrestore+0x1b/0x40 [ 256.478863] __napi_poll+0x29/0x160 [ 256.482409] net_rx_action+0x136/0x260 [ 256.486222] __do_softirq+0xe8/0x2e5 [ 256.489853] ? smpboot_thread_fn+0x2c/0x270 [ 256.494108] run_ksoftirqd+0x2a/0x50 [ 256.497747] smpboot_thread_fn+0x1c1/0x270 [ 256.501907] ? __pfx_smpboot_thread_fn+0x10/0x10 [ 256.506594] kthread+0xea/0x120 [ 256.509785] ? __pfx_kthread+0x10/0x10 [ 256.513597] ret_from_fork+0x29/0x50 [ 256.517238] </TASK> In fact, irqs were not disabled and napi managed to be scheduled and run while xsk_pool pointer was still valid, but SW ring of xdp_buff pointers was already freed. To fix this, call ice_qvec_dis_irq() after ice_vsi_stop_tx_ring(). Also while at it, remove redundant ice_clean_rx_ring() call - this is handled in ice_qp_clean_rings().

In the Linux kernel, the following vulnerability has been resolved: cifs: fix DFS traversal oops without CONFIG_CIFS_DFS_UPCALL When compiled with CONFIG_CIFS_DFS_UPCALL disabled, cifs_dfs_d_automount is NULL. cifs.ko logic for mapping CIFS_FATTR_DFS_REFERRAL attributes to S_AUTOMOUNT and corresponding dentry flags is retained regardless of CONFIG_CIFS_DFS_UPCALL, leading to a NULL pointer dereference in VFS follow_automount() when traversing a DFS referral link: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> __traverse_mounts+0xb5/0x220 ? cifs_revalidate_mapping+0x65/0xc0 [cifs] step_into+0x195/0x610 ? lookup_fast+0xe2/0xf0 path_lookupat+0x64/0x140 filename_lookup+0xc2/0x140 ? __create_object+0x299/0x380 ? kmem_cache_alloc+0x119/0x220 ? user_path_at_empty+0x31/0x50 user_path_at_empty+0x31/0x50 __x64_sys_chdir+0x2a/0xd0 ? exit_to_user_mode_prepare+0xca/0x100 do_syscall_64+0x42/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc This fix adds an inline cifs_dfs_d_automount() {return -EREMOTE} handler when CONFIG_CIFS_DFS_UPCALL is disabled. An alternative would be to avoid flagging S_AUTOMOUNT, etc. without CONFIG_CIFS_DFS_UPCALL. This approach was chosen as it provides more control over the error path.

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211_hwsim: Fix possible NULL dereference In a call to mac80211_hwsim_select_tx_link() the sta pointer might be NULL, thus need to check that it is not NULL before accessing it.

In the Linux kernel, the following vulnerability has been resolved: scsi: mpt3sas: Fix NULL pointer access in mpt3sas_transport_port_add() Port is allocated by sas_port_alloc_num() and rphy is allocated by either sas_end_device_alloc() or sas_expander_alloc(), all of which may return NULL. So we need to check the rphy to avoid possible NULL pointer access. If sas_rphy_add() returned with failure, rphy is set to NULL. We would access the rphy in the following lines which would also result NULL pointer access.

In the Linux kernel, the following vulnerability has been resolved: net/smc: Reset connection when trying to use SMCRv2 fails. We found a crash when using SMCRv2 with 2 Mellanox ConnectX-4. It can be reproduced by: - smc_run nginx - smc_run wrk -t 32 -c 500 -d 30 http://<ip>:<port> BUG: kernel NULL pointer dereference, address: 0000000000000014 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000108713067 P4D 8000000108713067 PUD 151127067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 4 PID: 2441 Comm: kworker/4:249 Kdump: loaded Tainted: G W E 6.4.0-rc1+ #42 Workqueue: smc_hs_wq smc_listen_work [smc] RIP: 0010:smc_clc_send_confirm_accept+0x284/0x580 [smc] RSP: 0018:ffffb8294b2d7c78 EFLAGS: 00010a06 RAX: ffff8f1873238880 RBX: ffffb8294b2d7dc8 RCX: 0000000000000000 RDX: 00000000000000b4 RSI: 0000000000000001 RDI: 0000000000b40c00 RBP: ffffb8294b2d7db8 R08: ffff8f1815c5860c R09: 0000000000000000 R10: 0000000000000400 R11: 0000000000000000 R12: ffff8f1846f56180 R13: ffff8f1815c5860c R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8f1aefd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000014 CR3: 00000001027a0001 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? mlx5_ib_map_mr_sg+0xa1/0xd0 [mlx5_ib] ? smcr_buf_map_link+0x24b/0x290 [smc] ? __smc_buf_create+0x4ee/0x9b0 [smc] smc_clc_send_accept+0x4c/0xb0 [smc] smc_listen_work+0x346/0x650 [smc] ? __schedule+0x279/0x820 process_one_work+0x1e5/0x3f0 worker_thread+0x4d/0x2f0 ? __pfx_worker_thread+0x10/0x10 kthread+0xe5/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2c/0x50 </TASK> During the CLC handshake, server sequentially tries available SMCRv2 and SMCRv1 devices in smc_listen_work(). If an SMCRv2 device is found. SMCv2 based link group and link will be assigned to the connection. Then assumed that some buffer assignment errors happen later in the CLC handshake, such as RMB registration failure, server will give up SMCRv2 and try SMCRv1 device instead. But the resources assigned to the connection won't be reset. When server tries SMCRv1 device, the connection creation process will be executed again. Since conn->lnk has been assigned when trying SMCRv2, it will not be set to the correct SMCRv1 link in smcr_lgr_conn_assign_link(). So in such situation, conn->lgr points to correct SMCRv1 link group but conn->lnk points to the SMCRv2 link mistakenly. Then in smc_clc_send_confirm_accept(), conn->rmb_desc->mr[link->link_idx] will be accessed. Since the link->link_idx is not correct, the related MR may not have been initialized, so crash happens. | Try SMCRv2 device first | |-> conn->lgr: assign existed SMCRv2 link group; | |-> conn->link: assign existed SMCRv2 link (link_idx may be 1 in SMC_LGR_SYMMETRIC); | |-> sndbuf & RMB creation fails, quit; | | Try SMCRv1 device then | |-> conn->lgr: create SMCRv1 link group and assign; | |-> conn->link: keep SMCRv2 link mistakenly; | |-> sndbuf & RMB creation succeed, only RMB->mr[link_idx = 0] | initialized. | | Then smc_clc_send_confirm_accept() accesses | conn->rmb_desc->mr[conn->link->link_idx, which is 1], then crash. v This patch tries to fix this by cleaning conn->lnk before assigning link. In addition, it is better to reset the connection and clean the resources assigned if trying SMCRv2 failed in buffer creation or registration.

In the Linux kernel, the following vulnerability has been resolved: net: wwan: iosm: fix NULL pointer dereference when removing device In suspend and resume cycle, the removal and rescan of device ends up in NULL pointer dereference. During driver initialization, if the ipc_imem_wwan_channel_init() fails to get the valid device capabilities it returns an error and further no resource (wwan struct) will be allocated. Now in this situation if driver removal procedure is initiated it would result in NULL pointer exception since unallocated wwan struct is dereferenced inside ipc_wwan_deinit(). ipc_imem_run_state_worker() to handle the called functions return value and to release the resource in failure case. It also reports the link down event in failure cases. The user space application can handle this event to do a device reset for restoring the device communication.

In the Linux kernel, the following vulnerability has been resolved: ice: Don't tx before switchdev is fully configured There is possibility that ice_eswitch_port_start_xmit might be called while some resources are still not allocated which might cause NULL pointer dereference. Fix this by checking if switchdev configuration was finished.

In the Linux kernel, the following vulnerability has been resolved: powerpc: Don't try to copy PPR for task with NULL pt_regs powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which from my (arguably very short) checking is not commonly done for other archs. This is fine, except when PF_IO_WORKER's have been created and the task does something that causes a coredump to be generated. Then we get this crash: Kernel attempted to read user page (160) - exploit attempt? (uid: 1000) BUG: Kernel NULL pointer dereference on read at 0x00000160 Faulting instruction address: 0xc0000000000c3a60 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0 REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8 ... NIP memcpy_power7+0x200/0x7d0 LR ppr_get+0x64/0xb0 Call Trace: ppr_get+0x40/0xb0 (unreliable) __regset_get+0x180/0x1f0 regset_get_alloc+0x64/0x90 elf_core_dump+0xb98/0x1b60 do_coredump+0x1c34/0x24a0 get_signal+0x71c/0x1410 do_notify_resume+0x140/0x6f0 interrupt_exit_user_prepare_main+0x29c/0x320 interrupt_exit_user_prepare+0x6c/0xa0 interrupt_return_srr_user+0x8/0x138 Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL pt_regs. Check for a valid pt_regs in both ppc_get/ppr_set, and return an error if not set. The actual error value doesn't seem to be important here, so just pick -EINVAL. [mpe: Trim oops in change log, add Fixes & Cc stable]

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix steering rules cleanup vport's mc, uc and multicast rules are not deleted in teardown path when EEH happens. Since the vport's promisc settings(uc, mc and all) in firmware are reset after EEH, mlx5 driver will try to delete the above rules in the initialization path. This cause kernel crash because these software rules are no longer valid. Fix by nullifying these rules right after delete to avoid accessing any dangling pointers. Call Trace: __list_del_entry_valid+0xcc/0x100 (unreliable) tree_put_node+0xf4/0x1b0 [mlx5_core] tree_remove_node+0x30/0x70 [mlx5_core] mlx5_del_flow_rules+0x14c/0x1f0 [mlx5_core] esw_apply_vport_rx_mode+0x10c/0x200 [mlx5_core] esw_update_vport_rx_mode+0xb4/0x180 [mlx5_core] esw_vport_change_handle_locked+0x1ec/0x230 [mlx5_core] esw_enable_vport+0x130/0x260 [mlx5_core] mlx5_eswitch_enable_sriov+0x2a0/0x2f0 [mlx5_core] mlx5_device_enable_sriov+0x74/0x440 [mlx5_core] mlx5_load_one+0x114c/0x1550 [mlx5_core] mlx5_pci_resume+0x68/0xf0 [mlx5_core] eeh_report_resume+0x1a4/0x230 eeh_pe_dev_traverse+0x98/0x170 eeh_handle_normal_event+0x3e4/0x640 eeh_handle_event+0x4c/0x370 eeh_event_handler+0x14c/0x210 kthread+0x168/0x1b0 ret_from_kernel_thread+0x5c/0x84

In the Linux kernel, the following vulnerability has been resolved: dm stats: check for and propagate alloc_percpu failure Check alloc_precpu()'s return value and return an error from dm_stats_init() if it fails. Update alloc_dev() to fail if dm_stats_init() does. Otherwise, a NULL pointer dereference will occur in dm_stats_cleanup() even if dm-stats isn't being actively used.

In the Linux kernel, the following vulnerability has been resolved: xfrm: add NULL check in xfrm_update_ae_params Normally, x->replay_esn and x->preplay_esn should be allocated at xfrm_alloc_replay_state_esn(...) in xfrm_state_construct(...), hence the xfrm_update_ae_params(...) is okay to update them. However, the current implementation of xfrm_new_ae(...) allows a malicious user to directly dereference a NULL pointer and crash the kernel like below. BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 8253067 P4D 8253067 PUD 8e0e067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 PID: 98 Comm: poc.npd Not tainted 6.4.0-rc7-00072-gdad9774deaf1 #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.o4 RIP: 0010:memcpy_orig+0xad/0x140 Code: e8 4c 89 5f e0 48 8d 7f e0 73 d2 83 c2 20 48 29 d6 48 29 d7 83 fa 10 72 34 4c 8b 06 4c 8b 4e 08 c RSP: 0018:ffff888008f57658 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff888008bd0000 RCX: ffffffff8238e571 RDX: 0000000000000018 RSI: ffff888007f64844 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888008f57818 R13: ffff888007f64aa4 R14: 0000000000000000 R15: 0000000000000000 FS: 00000000014013c0(0000) GS:ffff88806d600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000054d8000 CR4: 00000000000006f0 Call Trace: <TASK> ? __die+0x1f/0x70 ? page_fault_oops+0x1e8/0x500 ? __pfx_is_prefetch.constprop.0+0x10/0x10 ? __pfx_page_fault_oops+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x11/0x40 ? fixup_exception+0x36/0x460 ? _raw_spin_unlock_irqrestore+0x11/0x40 ? exc_page_fault+0x5e/0xc0 ? asm_exc_page_fault+0x26/0x30 ? xfrm_update_ae_params+0xd1/0x260 ? memcpy_orig+0xad/0x140 ? __pfx__raw_spin_lock_bh+0x10/0x10 xfrm_update_ae_params+0xe7/0x260 xfrm_new_ae+0x298/0x4e0 ? __pfx_xfrm_new_ae+0x10/0x10 ? __pfx_xfrm_new_ae+0x10/0x10 xfrm_user_rcv_msg+0x25a/0x410 ? __pfx_xfrm_user_rcv_msg+0x10/0x10 ? __alloc_skb+0xcf/0x210 ? stack_trace_save+0x90/0xd0 ? filter_irq_stacks+0x1c/0x70 ? __stack_depot_save+0x39/0x4e0 ? __kasan_slab_free+0x10a/0x190 ? kmem_cache_free+0x9c/0x340 ? netlink_recvmsg+0x23c/0x660 ? sock_recvmsg+0xeb/0xf0 ? __sys_recvfrom+0x13c/0x1f0 ? __x64_sys_recvfrom+0x71/0x90 ? do_syscall_64+0x3f/0x90 ? entry_SYSCALL_64_after_hwframe+0x72/0xdc ? copyout+0x3e/0x50 netlink_rcv_skb+0xd6/0x210 ? __pfx_xfrm_user_rcv_msg+0x10/0x10 ? __pfx_netlink_rcv_skb+0x10/0x10 ? __pfx_sock_has_perm+0x10/0x10 ? mutex_lock+0x8d/0xe0 ? __pfx_mutex_lock+0x10/0x10 xfrm_netlink_rcv+0x44/0x50 netlink_unicast+0x36f/0x4c0 ? __pfx_netlink_unicast+0x10/0x10 ? netlink_recvmsg+0x500/0x660 netlink_sendmsg+0x3b7/0x700 This Null-ptr-deref bug is assigned CVE-2023-3772. And this commit adds additional NULL check in xfrm_update_ae_params to fix the NPD.

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix null pointer dereference in tracing_err_log_open() Fix an issue in function 'tracing_err_log_open'. The function doesn't call 'seq_open' if the file is opened only with write permissions, which results in 'file->private_data' being left as null. If we then use 'lseek' on that opened file, 'seq_lseek' dereferences 'file->private_data' in 'mutex_lock(&m->lock)', resulting in a kernel panic. Writing to this node requires root privileges, therefore this bug has very little security impact. Tracefs node: /sys/kernel/tracing/error_log Example Kernel panic: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038 Call trace: mutex_lock+0x30/0x110 seq_lseek+0x34/0xb8 __arm64_sys_lseek+0x6c/0xb8 invoke_syscall+0x58/0x13c el0_svc_common+0xc4/0x10c do_el0_svc+0x24/0x98 el0_svc+0x24/0x88 el0t_64_sync_handler+0x84/0xe4 el0t_64_sync+0x1b4/0x1b8 Code: d503201f aa0803e0 aa1f03e1 aa0103e9 (c8e97d02) ---[ end trace 561d1b49c12cf8a5 ]--- Kernel panic - not syncing: Oops: Fatal exception

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix null-ptr-deref on inode->i_op in ntfs_lookup() Syzbot reported a null-ptr-deref bug: ntfs3: loop0: Different NTFS' sector size (1024) and media sector size (512) ntfs3: loop0: Mark volume as dirty due to NTFS errors general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] RIP: 0010:d_flags_for_inode fs/dcache.c:1980 [inline] RIP: 0010:__d_add+0x5ce/0x800 fs/dcache.c:2796 Call Trace: <TASK> d_splice_alias+0x122/0x3b0 fs/dcache.c:3191 lookup_open fs/namei.c:3391 [inline] open_last_lookups fs/namei.c:3481 [inline] path_openat+0x10e6/0x2df0 fs/namei.c:3688 do_filp_open+0x264/0x4f0 fs/namei.c:3718 do_sys_openat2+0x124/0x4e0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_open fs/open.c:1334 [inline] __se_sys_open fs/open.c:1330 [inline] __x64_sys_open+0x221/0x270 fs/open.c:1330 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL. And a null-ptr-deref may happen: ntfs_lookup() dir_search_u() # inode->i_op is set to NULL d_splice_alias() __d_add() d_flags_for_inode() # inode->i_op->get_link null-ptr-deref Fix this by adding a Check on inode->i_op before calling the d_splice_alias() function.

In the Linux kernel, the following vulnerability has been resolved: icmp6: Fix null-ptr-deref of ip6_null_entry->rt6i_idev in icmp6_dev(). With some IPv6 Ext Hdr (RPL, SRv6, etc.), we can send a packet that has the link-local address as src and dst IP and will be forwarded to an external IP in the IPv6 Ext Hdr. For example, the script below generates a packet whose src IP is the link-local address and dst is updated to 11::. # for f in $(find /proc/sys/net/ -name *seg6_enabled*); do echo 1 > $f; done # python3 >>> from socket import * >>> from scapy.all import * >>> >>> SRC_ADDR = DST_ADDR = "fe80::5054:ff:fe12:3456" >>> >>> pkt = IPv6(src=SRC_ADDR, dst=DST_ADDR) >>> pkt /= IPv6ExtHdrSegmentRouting(type=4, addresses=["11::", "22::"], segleft=1) >>> >>> sk = socket(AF_INET6, SOCK_RAW, IPPROTO_RAW) >>> sk.sendto(bytes(pkt), (DST_ADDR, 0)) For such a packet, we call ip6_route_input() to look up a route for the next destination in these three functions depending on the header type. * ipv6_rthdr_rcv() * ipv6_rpl_srh_rcv() * ipv6_srh_rcv() If no route is found, ip6_null_entry is set to skb, and the following dst_input(skb) calls ip6_pkt_drop(). Finally, in icmp6_dev(), we dereference skb_rt6_info(skb)->rt6i_idev->dev as the input device is the loopback interface. Then, we have to check if skb_rt6_info(skb)->rt6i_idev is NULL or not to avoid NULL pointer deref for ip6_null_entry. BUG: kernel NULL pointer dereference, address: 0000000000000000 PF: supervisor read access in kernel mode PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 157 Comm: python3 Not tainted 6.4.0-11996-gb121d614371c #35 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:icmp6_send (net/ipv6/icmp.c:436 net/ipv6/icmp.c:503) Code: fe ff ff 48 c7 40 30 c0 86 5d 83 e8 c6 44 1c 00 e9 c8 fc ff ff 49 8b 46 58 48 83 e0 fe 0f 84 4a fb ff ff 48 8b 80 d0 00 00 00 <48> 8b 00 44 8b 88 e0 00 00 00 e9 34 fb ff ff 4d 85 ed 0f 85 69 01 RSP: 0018:ffffc90000003c70 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 00000000000000e0 RDX: 0000000000000021 RSI: 0000000000000000 RDI: ffff888006d72a18 RBP: ffffc90000003d80 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc90000003d98 R11: 0000000000000040 R12: ffff888006d72a10 R13: 0000000000000000 R14: ffff8880057fb800 R15: ffffffff835d86c0 FS: 00007f9dc72ee740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000057b2000 CR4: 00000000007506f0 PKRU: 55555554 Call Trace: <IRQ> ip6_pkt_drop (net/ipv6/route.c:4513) ipv6_rthdr_rcv (net/ipv6/exthdrs.c:640 net/ipv6/exthdrs.c:686) ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5)) ip6_input_finish (./include/linux/rcupdate.h:781 net/ipv6/ip6_input.c:483) __netif_receive_skb_one_core (net/core/dev.c:5455) process_backlog (./include/linux/rcupdate.h:781 net/core/dev.c:5895) __napi_poll (net/core/dev.c:6460) net_rx_action (net/core/dev.c:6529 net/core/dev.c:6660) __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554) do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) </IRQ> <TASK> __local_bh_enable_ip (kernel/softirq.c:381) __dev_queue_xmit (net/core/dev.c:4231) ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:135) rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914) sock_sendmsg (net/socket.c:725 net/socket.c:748) __sys_sendto (net/socket.c:2134) __x64_sys_sendto (net/socket.c:2146 net/socket.c:2142 net/socket.c:2142) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f9dc751baea Code: d8 64 89 02 48 c7 c0 ff f ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ice: Block switchdev mode when ADQ is active and vice versa ADQ and switchdev are not supported simultaneously. Enabling both at the same time can result in nullptr dereference. To prevent this, check if ADQ is active when changing devlink mode to switchdev mode, and check if switchdev is active when enabling ADQ.

In the Linux kernel, the following vulnerability has been resolved: wifi: nl80211: fix NULL-ptr deref in offchan check If, e.g. in AP mode, the link was already created by userspace but not activated yet, it has a chandef but the chandef isn't valid and has no channel. Check for this and ignore this link.

In the Linux kernel, the following vulnerability has been resolved: scsi: storvsc: Fix handling of virtual Fibre Channel timeouts Hyper-V provides the ability to connect Fibre Channel LUNs to the host system and present them in a guest VM as a SCSI device. I/O to the vFC device is handled by the storvsc driver. The storvsc driver includes a partial integration with the FC transport implemented in the generic portion of the Linux SCSI subsystem so that FC attributes can be displayed in /sys. However, the partial integration means that some aspects of vFC don't work properly. Unfortunately, a full and correct integration isn't practical because of limitations in what Hyper-V provides to the guest. In particular, in the context of Hyper-V storvsc, the FC transport timeout function fc_eh_timed_out() causes a kernel panic because it can't find the rport and dereferences a NULL pointer. The original patch that added the call from storvsc_eh_timed_out() to fc_eh_timed_out() is faulty in this regard. In many cases a timeout is due to a transient condition, so the situation can be improved by just continuing to wait like with other I/O requests issued by storvsc, and avoiding the guaranteed panic. For a permanent failure, continuing to wait may result in a hung thread instead of a panic, which again may be better. So fix the panic by removing the storvsc call to fc_eh_timed_out(). This allows storvsc to keep waiting for a response. The change has been tested by users who experienced a panic in fc_eh_timed_out() due to transient timeouts, and it solves their problem. In the future we may want to deprecate the vFC functionality in storvsc since it can't be fully fixed. But it has current users for whom it is working well enough, so it should probably stay for a while longer.

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Check kzalloc() in lpfc_sli4_cgn_params_read() If kzalloc() fails in lpfc_sli4_cgn_params_read(), then we rely on lpfc_read_object()'s routine to NULL check pdata. Currently, an early return error is thrown from lpfc_read_object() to protect us from NULL ptr dereference, but the errno code is -ENODEV. Change the errno code to a more appropriate -ENOMEM.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: pcie: fix NULL pointer dereference in iwl_pcie_irq_rx_msix_handler() rxq can be NULL only when trans_pcie->rxq is NULL and entry->entry is zero. For the case when entry->entry is not equal to 0, rxq won't be NULL even if trans_pcie->rxq is NULL. Modify checker to check for trans_pcie->rxq.

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler() When performing a stress test on SMC-R by rmmod mlx5_ib driver during the wrk/nginx test, we found that there is a probability of triggering a panic while terminating all link groups. This issue dues to the race between smc_smcr_terminate_all() and smc_buf_create(). smc_smcr_terminate_all smc_buf_create /* init */ conn->sndbuf_desc = NULL; ... __smc_lgr_terminate smc_conn_kill smc_close_abort smc_cdc_get_slot_and_msg_send __softirqentry_text_start smc_wr_tx_process_cqe smc_cdc_tx_handler READ(conn->sndbuf_desc->len); /* panic dues to NULL sndbuf_desc */ conn->sndbuf_desc = xxx; This patch tries to fix the issue by always to check the sndbuf_desc before send any cdc msg, to make sure that no null pointer is seen during cqe processing.