NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix NULL pointer dereference in __unix_needs_revalidation When receiving file descriptors via SCM_RIGHTS, both the socket pointer and the socket's sk pointer can be NULL during socket setup or teardown, causing NULL pointer dereferences in __unix_needs_revalidation(). This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new __unix_needs_revalidation() function was added without proper NULL checks. The crash manifests as: BUG: kernel NULL pointer dereference, address: 0x0000000000000018 RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0) Call Trace: apparmor_file_receive+0x42/0x80 security_file_receive+0x2e/0x50 receive_fd+0x1d/0xf0 scm_detach_fds+0xad/0x1c0 The function dereferences sock->sk->sk_family without checking if either sock or sock->sk is NULL first. Add NULL checks for both sock and sock->sk before accessing sk_family.Show less

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix invalid deref of rawdata when export_binary is unset If the export_binary parameter is disabled on runtime, profiles that were loaded before that will still have their rawdata stored in apparmorfs, with a symbolic link to the rawdata on the policy directory. When one of those profiles are replaced, the rawdata is set to NULL, but when trying to resolve the symbolic links to rawdata for that profile, it will try to dereference profile->rawdata->name when profile->rawdata is now NULL causing an oops. Fix it by checking if rawdata is set. [ 168.653080] BUG: kernel NULL pointer dereference, address: 0000000000000088 [ 168.657420] #PF: supervisor read access in kernel mode [ 168.660619] #PF: error_code(0x0000) - not-present page [ 168.663613] PGD 0 P4D 0 [ 168.665450] Oops: Oops: 0000 [#1] SMP NOPTI [ 168.667836] CPU: 1 UID: 0 PID: 1729 Comm: ls Not tainted 6.19.0-rc7+ #3 PREEMPT(voluntary) [ 168.672308] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 168.679327] RIP: 0010:rawdata_get_link_base.isra.0+0x23/0x330 [ 168.682768] Code: 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 89 55 d0 48 85 ff 0f 84 e3 01 00 00 <48> 83 3c 25 88 00 00 00 00 0f 84 d4 01 00 00 49 89 f6 49 89 cc e8 [ 168.689818] RSP: 0018:ffffcdcb8200fb80 EFLAGS: 00010282 [ 168.690871] RAX: ffffffffaee74ec0 RBX: 0000000000000000 RCX: ffffffffb0120158 [ 168.692251] RDX: ffffcdcb8200fbe0 RSI: ffff88c187c9fa80 RDI: ffff88c186c98a80 [ 168.693593] RBP: ffffcdcb8200fbc0 R08: 0000000000000000 R09: 0000000000000000 [ 168.694941] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88c186c98a80 [ 168.696289] R13: 00007fff005aaa20 R14: 0000000000000080 R15: ffff88c188f4fce0 [ 168.697637] FS: 0000790e81c58280(0000) GS:ffff88c20a957000(0000) knlGS:0000000000000000 [ 168.699227] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 168.700349] CR2: 0000000000000088 CR3: 000000012fd3e000 CR4: 0000000000350ef0 [ 168.701696] Call Trace: [ 168.702325] <TASK> [ 168.702995] rawdata_get_link_data+0x1c/0x30 [ 168.704145] vfs_readlink+0xd4/0x160 [ 168.705152] do_readlinkat+0x114/0x180 [ 168.706214] __x64_sys_readlink+0x1e/0x30 [ 168.708653] x64_sys_call+0x1d77/0x26b0 [ 168.709525] do_syscall_64+0x81/0x500 [ 168.710348] ? do_statx+0x72/0xb0 [ 168.711109] ? putname+0x3e/0x80 [ 168.711845] ? __x64_sys_statx+0xb7/0x100 [ 168.712711] ? x64_sys_call+0x10fc/0x26b0 [ 168.713577] ? do_syscall_64+0xbf/0x500 [ 168.714412] ? do_user_addr_fault+0x1d2/0x8d0 [ 168.715404] ? irqentry_exit+0xb2/0x740 [ 168.716359] ? exc_page_fault+0x90/0x1b0 [ 168.717307] entry_SYSCALL_64_after_hwframe+0x76/0x7eShow less

In the Linux kernel, the following vulnerability has been resolved: ASoC: nau8821: Cancel delayed work on component remove Attempting to unload the driver while a jack detection work is pending would likely crash the kernel when it is eventually scheduled for execution: [ 1984.896308] BUG: unable to handle page fault for address: ffffffffc10c2a20 [...] [ 1984.896388] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024 [ 1984.896396] Workqueue: events nau8821_jdet_work [snd_soc_nau8821] [ 1984.896414] RIP: 0010:__mutex_lock+0x9f/0x11d0 [...] [ 1984.896504] Call Trace: [ 1984.896511] <TASK> [ 1984.896524] ? snd_soc_dapm_disable_pin+0x26/0x60 [snd_soc_core] [ 1984.896572] ? snd_soc_dapm_disable_pin+0x26/0x60 [snd_soc_core] [ 1984.896596] snd_soc_dapm_disable_pin+0x26/0x60 [snd_soc_core] [ 1984.896622] nau8821_jdet_work+0xeb/0x1e0 [snd_soc_nau8821] [ 1984.896636] process_one_work+0x211/0x590 [ 1984.896649] ? srso_return_thunk+0x5/0x5f [ 1984.896670] worker_thread+0x1cd/0x3a0 Cancel unscheduled jdet_work or wait for its execution to finish before the component driver gets removed.Show less

In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Fix a crash due to incorrect cleanup usage of kfree Annotating a local pointer variable, which will be assigned with the kmalloc-family functions, with the `__cleanup(kfree)` attribute will make the address of the local variable, rather than the address returned by kmalloc, passed to kfree directly and lead to a crash due to invalid deallocation of stack address. According to other places in the repo, the correct usage should be `__free(kfree)`. The code coincidentally compiled because the parameter type `void *` of kfree is compatible with the desired type `struct { ... } **`.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/exynos: vidi: fix to avoid directly dereferencing user pointer In vidi_connection_ioctl(), vidi->edid(user pointer) is directly dereferenced in the kernel. This allows arbitrary kernel memory access from the user space, so instead of directly accessing the user pointer in the kernel, we should modify it to copy edid to kernel memory using copy_from_user() and use it.Show less

In the Linux kernel, the following vulnerability has been resolved: ovpn: tcp - don't deref NULL sk_socket member after tcp_close() When deleting a peer in case of keepalive expiration, the peer is removed from the OpenVPN hashtable and is temporary inserted in a "release list" for further processing. This happens in: ovpn_peer_keepalive_work() unlock_ovpn(release_list) This processing includes detaching from the socket being used to talk to this peer, by restoring its original proto and socket ops/callbacks. In case of TCP it may happen that, while the peer is sitting in the release list, userspace decides to close the socket. This will result in a concurrent execution of: tcp_close(sk) __tcp_close(sk) sock_orphan(sk) sk_set_socket(sk, NULL) The last function call will set sk->sk_socket to NULL. When the releasing routine is resumed, ovpn_tcp_socket_detach() will attempt to dereference sk->sk_socket to restore its original ops member. This operation will crash due to sk->sk_socket being NULL. Fix this race condition by testing-and-accessing sk->sk_socket atomically under sk->sk_callback_lock.Show less

In the Linux kernel, the following vulnerability has been resolved: usb: cdns3: fix role switching during resume If the role change while we are suspended, the cdns3 driver switches to the new mode during resume. However, switching to host mode in this context causes a NULL pointer dereference. The host role's start() operation registers a xhci-hcd device, but its probe is deferred while we are in the resume path. The host role's resume() operation assumes the xhci-hcd device is already probed, which is not the case, leading to the dereference. Since the start() operation of the new role is already called, the resume operation can be skipped. So skip the resume operation for the new role if a role switch occurs during resume. Once the resume sequence is complete, the xhci-hcd device can be probed in case of host mode. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000208 Mem abort info: ... Data abort info: ... [0000000000000208] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 146 Comm: sh Not tainted 6.19.0-rc7-00013-g6e64f4aabfae-dirty #135 PREEMPT Hardware name: Texas Instruments J7200 EVM (DT) pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : usb_hcd_is_primary_hcd+0x0/0x1c lr : cdns_host_resume+0x24/0x5c ... Call trace: usb_hcd_is_primary_hcd+0x0/0x1c (P) cdns_resume+0x6c/0xbc cdns3_controller_resume.isra.0+0xe8/0x17c cdns3_plat_resume+0x18/0x24 platform_pm_resume+0x2c/0x68 dpm_run_callback+0x90/0x248 device_resume+0x100/0x24c dpm_resume+0x190/0x2ec dpm_resume_end+0x18/0x34 suspend_devices_and_enter+0x2b0/0xa44 pm_suspend+0x16c/0x5fc state_store+0x80/0xec kobj_attr_store+0x18/0x2c sysfs_kf_write+0x7c/0x94 kernfs_fop_write_iter+0x130/0x1dc vfs_write+0x240/0x370 ksys_write+0x70/0x108 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x48/0x10c el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x34/0x108 el0t_64_sync_handler+0xa0/0xe4 el0t_64_sync+0x198/0x19c Code: 52800003 f9407ca5 d63f00a0 17ffffe4 (f9410401) ---[ end trace 0000000000000000 ]---Show less

In the Linux kernel, the following vulnerability has been resolved: HID: intel-ish-hid: fix NULL-ptr-deref in ishtp_bus_remove_all_clients During a warm reset flow, the cl->device pointer may be NULL if the reset occurs while clients are still being enumerated. Accessing cl->device->reference_count without a NULL check leads to a kernel panic. This issue was identified during multi-unit warm reboot stress clycles. Add a defensive NULL check for cl->device to ensure stability under such intensive testing conditions. KASAN: null-ptr-deref in range [0000000000000000-0000000000000007] Workqueue: ish_fw_update_wq fw_reset_work_fn Call Trace: ishtp_bus_remove_all_clients+0xbe/0x130 [intel_ishtp] ishtp_reset_handler+0x85/0x1a0 [intel_ishtp] fw_reset_work_fn+0x8a/0xc0 [intel_ish_ipc]Show less

In the Linux kernel, the following vulnerability has been resolved: arm64/gcs: Fix error handling in arch_set_shadow_stack_status() alloc_gcs() returns an error-encoded pointer on failure, which comes from do_mmap(), not NULL. The current NULL check fails to detect errors, which could lead to using an invalid GCS address. Use IS_ERR_VALUE() to properly detect errors, consistent with the check in gcs_alloc_thread_stack().Show less

In the Linux kernel, the following vulnerability has been resolved: phy: freescale: imx8qm-hsio: fix NULL pointer dereference During the probe the refclk_pad pointer is set to NULL if the 'fsl,refclk-pad-mode' property is not defined in the devicetree node. But in imx_hsio_configure_clk_pad() this pointer is unconditionally used which could result in a NULL pointer dereference. So check the pointer before to use it.Show less

In the Linux kernel, the following vulnerability has been resolved: power: supply: wm97xx: Fix NULL pointer dereference in power_supply_changed() In `probe()`, `request_irq()` is called before allocating/registering a `power_supply` handle. If an interrupt is fired between the call to `request_irq()` and `power_supply_register()`, the `power_supply` handle will be used uninitialized in `power_supply_changed()` in `wm97xx_bat_update()` (triggered from the interrupt handler). This will lead to a `NULL` pointer dereference since Fix this racy `NULL` pointer dereference by making sure the IRQ is requested _after_ the registration of the `power_supply` handle. Since the IRQ is the last thing requests in the `probe()` now, remove the error path for freeing it. Instead add one for unregistering the `power_supply` handle when IRQ request fails.Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: csiostor: Fix dereference of null pointer rn The error exit path when rn is NULL ends up deferencing the null pointer rn via the use of the macro CSIO_INC_STATS. Fix this by adding a new error return path label after the use of the macro to avoid the deference.Show less

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix NULL sock in aa_sock_file_perm Deal with the potential that sock and sock-sk can be NULL during socket setup or teardown. This could lead to an oops. The fix for NULL pointer dereference in __unix_needs_revalidation shows this is at least possible for af_unix sockets. While the fix for af_unix sockets applies for newer mediation this is still the fall back path for older af_unix mediation and other sockets, so ensure it is covered.Show less

In the Linux kernel, the following vulnerability has been resolved: accel/amdxdna: Fix potential NULL pointer dereference in context cleanup aie_destroy_context() is invoked during error handling in aie2_create_context(). However, aie_destroy_context() assumes that the context's mailbox channel pointer is non-NULL. If mailbox channel creation fails, the pointer remains NULL and calling aie_destroy_context() can lead to a NULL pointer dereference. In aie2_create_context(), replace aie_destroy_context() with a function which request firmware to remove the context created previously.Show less

In the Linux kernel, the following vulnerability has been resolved: drm/panthor: Fix NULL pointer dereference on panthor_fw_unplug This patch removes the MCU halt and wait for halt procedures during panthor_fw_unplug() as the MCU can be in a variety of states or the FW may not even be loaded/initialized at all, the latter of which can lead to a NULL pointer dereference. It should be safe on unplug to just disable the MCU without waiting for it to halt as it may not be able to.Show less

In the Linux kernel, the following vulnerability has been resolved: bareudp: fix NULL pointer dereference in bareudp_fill_metadata_dst() bareudp_fill_metadata_dst() passes bareudp->sock to udp_tunnel6_dst_lookup() in the IPv6 path without a NULL check. The socket is only created in bareudp_open() and NULLed in bareudp_stop(), so calling this function while the device is down triggers a NULL dereference via sock->sk. BUG: kernel NULL pointer dereference, address: 0000000000000018 RIP: 0010:udp_tunnel6_dst_lookup (net/ipv6/ip6_udp_tunnel.c:160) Call Trace: <TASK> bareudp_fill_metadata_dst (drivers/net/bareudp.c:532) do_execute_actions (net/openvswitch/actions.c:901) ovs_execute_actions (net/openvswitch/actions.c:1589) ovs_packet_cmd_execute (net/openvswitch/datapath.c:700) genl_family_rcv_msg_doit (net/netlink/genetlink.c:1114) genl_rcv_msg (net/netlink/genetlink.c:1209) netlink_rcv_skb (net/netlink/af_netlink.c:2550) </TASK> Add a NULL check returning -ESHUTDOWN, consistent with the xmit paths in the same driver.Show less

In the Linux kernel, the following vulnerability has been resolved: net/sched: taprio: fix NULL pointer dereference in class dump When a TAPRIO child qdisc is deleted via RTM_DELQDISC, taprio_graft() is called with new == NULL and stores NULL into q->qdiscs[cl - 1]. Subsequent RTM_GETTCLASS dump operations walk all classes via taprio_walk() and call taprio_dump_class(), which calls taprio_leaf() returning the NULL pointer, then dereferences it to read child->handle, causing a kernel NULL pointer dereference. The bug is reachable with namespace-scoped CAP_NET_ADMIN on any kernel with CONFIG_NET_SCH_TAPRIO enabled. On systems with unprivileged user namespaces enabled, an unprivileged local user can trigger a kernel panic by creating a taprio qdisc inside a new network namespace, grafting an explicit child qdisc, deleting it, and requesting a class dump. The RTM_GETTCLASS dump itself requires no capability. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] RIP: 0010:taprio_dump_class (net/sched/sch_taprio.c:2478) Call Trace: <TASK> tc_fill_tclass (net/sched/sch_api.c:1966) qdisc_class_dump (net/sched/sch_api.c:2326) taprio_walk (net/sched/sch_taprio.c:2514) tc_dump_tclass_qdisc (net/sched/sch_api.c:2352) tc_dump_tclass_root (net/sched/sch_api.c:2370) tc_dump_tclass (net/sched/sch_api.c:2431) rtnl_dumpit (net/core/rtnetlink.c:6864) netlink_dump (net/netlink/af_netlink.c:2325) rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) netlink_rcv_skb (net/netlink/af_netlink.c:2550) </TASK> Fix this by substituting &noop_qdisc when new is NULL in taprio_graft(), a common pattern used by other qdiscs (e.g., multiq_graft()) to ensure the q->qdiscs[] slots are never NULL. This makes control-plane dump paths safe without requiring individual NULL checks. Since the data-plane paths (taprio_enqueue and taprio_dequeue_from_txq) previously had explicit NULL guards that would drop/skip the packet cleanly, update those checks to test for &noop_qdisc instead. Without this, packets would reach taprio_enqueue_one() which increments the root qdisc's qlen and backlog before calling the child's enqueue; noop_qdisc drops the packet but those counters are never rolled back, permanently inflating the root qdisc's statistics. After this change *old can be a valid qdisc, NULL, or &noop_qdisc. Only call qdisc_put(*old) in the first case to avoid decreasing noop_qdisc's refcount, which was never increased.Show less

In the Linux kernel, the following vulnerability has been resolved: slip: reject VJ receive packets on instances with no rstate array slhc_init() accepts rslots == 0 as a valid configuration, with the documented meaning of 'no receive compression'. In that case the allocation loop in slhc_init() is skipped, so comp->rstate stays NULL and comp->rslot_limit stays 0 (from the kzalloc of struct slcompress). The receive helpers do not defend against that configuration. slhc_uncompress() dereferences comp->rstate[x] when the VJ header carries an explicit connection ID, and slhc_remember() later assigns cs = &comp->rstate[...] after only comparing the packet's slot number to comp->rslot_limit. Because rslot_limit is 0, slot 0 passes the range check, and the code dereferences a NULL rstate. The configuration is reachable in-tree through PPP. PPPIOCSMAXCID stores its argument in a signed int, and (val >> 16) uses arithmetic shift. Passing 0xffff0000 therefore sign-extends to -1, so val2 + 1 is 0 and ppp_generic.c ends up calling slhc_init(0, 1). Because /dev/ppp open is gated by ns_capable(CAP_NET_ADMIN), the whole path is reachable from an unprivileged user namespace. Once the malformed VJ state is installed, any inbound VJ-compressed or VJ-uncompressed frame that selects slot 0 crashes the kernel in softirq context: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:slhc_uncompress (drivers/net/slip/slhc.c:519) Call Trace: <TASK> ppp_receive_nonmp_frame (drivers/net/ppp/ppp_generic.c:2466) ppp_input (drivers/net/ppp/ppp_generic.c:2359) ppp_async_process (drivers/net/ppp/ppp_async.c:492) tasklet_action_common (kernel/softirq.c:926) handle_softirqs (kernel/softirq.c:623) run_ksoftirqd (kernel/softirq.c:1055) smpboot_thread_fn (kernel/smpboot.c:160) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) </TASK> Reject the receive side on such instances instead of touching rstate. slhc_uncompress() falls through to its existing 'bad' label, which bumps sls_i_error and enters the toss state. slhc_remember() mirrors that with an explicit sls_i_error increment followed by slhc_toss(); the sls_i_runt counter is not used here because a missing rstate is an internal configuration state, not a runt packet. The transmit path is unaffected: the only in-tree caller that picks rslots from userspace (ppp_generic.c) still supplies tslots >= 1, and slip.c always calls slhc_init(16, 16), so comp->tstate remains valid and slhc_compress() continues to work.Show less

In the Linux kernel, the following vulnerability has been resolved: bpf: fix end-of-list detection in cgroup_storage_get_next_key() list_next_entry() never returns NULL -- when the current element is the last entry it wraps to the list head via container_of(). The subsequent NULL check is therefore dead code and get_next_key() never returns -ENOENT for the last element, instead reading storage->key from a bogus pointer that aliases internal map fields and copying the result to userspace. Replace it with list_entry_is_head() so the function correctly returns -ENOENT when there are no more entries.Show less

A security flaw has been discovered in GPAC up to 2.4.0. Affected is the function MergeFragment of the file src/isomedia/isom_intern.c of the component MP4Box. The manipulation results in null pointer dereference. The attack needs to be approached locally. The exploit has been released to the public and may be used for attacks. The patch is identified as 525bf1af642c30af04e4df5345e6d798c0a4d8a1. It is advisable to implement a patch to correct this issue.Show less