The Linux Kernel, the operating system core itself.

Security Fix(es):

In the Linux kernel, the following vulnerability has been resolved:

powerpc/kprobes: Fix null pointer reference in arch_prepare_kprobe()

I found a null pointer reference in arch_prepare_kprobe():

echo 'p cmdline_proc_show' > kprobe_events

echo 'p cmdline_proc_show+16' >> kprobe_events

Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc000000000050bfc Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: CPU: 0 PID: 122 Comm: sh Not tainted 6.0.0-rc3-00007-gdcf8e5633e2e #10 NIP: c000000000050bfc LR: c000000000050bec CTR: 0000000000005bdc REGS: c0000000348475b0 TRAP: 0300 Not tainted (6.0.0-rc3-00007-gdcf8e5633e2e) MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 88002444 XER: 20040006 CFAR: c00000000022d100 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0 ... NIP arch_prepare_kprobe+0x10c/0x2d0 LR arch_prepare_kprobe+0xfc/0x2d0 Call Trace: 0xc0000000012f77a0 (unreliable) register_kprobe+0x3c0/0x7a0 __register_trace_kprobe+0x140/0x1a0 __trace_kprobe_create+0x794/0x1040 trace_probe_create+0xc4/0xe0 create_or_delete_trace_kprobe+0x2c/0x80 trace_parse_run_command+0xf0/0x210 probes_write+0x20/0x40 vfs_write+0xfc/0x450 ksys_write+0x84/0x140 system_call_exception+0x17c/0x3a0 system_call_vectored_common+0xe8/0x278 --- interrupt: 3000 at 0x7fffa5682de0 NIP: 00007fffa5682de0 LR: 0000000000000000 CTR: 0000000000000000 REGS: c000000034847e80 TRAP: 3000 Not tainted (6.0.0-rc3-00007-gdcf8e5633e2e) MSR: 900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 44002408 XER: 00000000

The address being probed has some special:

cmdline_proc_show: Probe based on ftrace cmdline_proc_show+16: Probe for the next instruction at the ftrace location

The ftrace-based kprobe does not generate kprobe::ainsn::insn, it gets set to NULL. In arch_prepare_kprobe() it will check for:

... prev = get_kprobe(p->addr - 1); preempt_enable_no_resched(); if (prev && ppc_inst_prefixed(ppc_inst_read(prev->ainsn.insn))) { ...

If prev is based on ftrace, 'ppc_inst_read(prev->ainsn.insn)' will occur with a null pointer reference. At this point prev->addr will not be a prefixed instruction, so the check can be skipped.

Check if prev is ftrace-based kprobe before reading 'prev->ainsn.insn' to fix this problem.

mpe: Trim oops

In the Linux kernel, the following vulnerability has been resolved:

erofs: validate the extent length for uncompressed pclusters

syzkaller reported a KASAN use-after-free: https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2

The referenced fuzzed image actually has two issues:

• m_pa == 0 as a non-inlined pcluster;
• The logical length is longer than its physical length.

The first issue has already been addressed. This patch addresses the second issue by checking the extent length validity.(CVE-2022-50746)

In the Linux kernel, the following vulnerability has been resolved:

smc: Fix use-after-free in tcp_write_timer_handler().

With Eric's ref tracker, syzbot finally found a repro for use-after-free in tcp_write_timer_handler() by kernel TCP sockets. [0]

If SMC creates a kernel socket in __smc_create(), the kernel socket is supposed to be freed in smc_clcsock_release() by calling sock_release() when we close() the parent SMC socket.

However, at the end of smc_clcsock_release(), the kernel socket's sk_state might not be TCP_CLOSE. This means that we have not called inet_csk_destroy_sock() in __tcp_close() and have not stopped the TCP timers.

The kernel socket's TCP timers can be fired later, so we need to hold a refcnt for net as we do for MPTCP subflows in mptcp_subflow_create_socket().

[0]: leaked reference. sk_alloc (./include/net/net_namespace.h:335 net/core/sock.c:2108) inet_create (net/ipv4/af_inet.c:319 net/ipv4/af_inet.c:244) __sock_create (net/socket.c:1546) smc_create (net/smc/af_smc.c:3269 net/smc/af_smc.c:3284) __sock_create (net/socket.c:1546) __sys_socket (net/socket.c:1634 net/socket.c:1618 net/socket.c:1661) __x64_sys_socket (net/socket.c:1672) 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)

BUG: KASAN: slab-use-after-free in tcp_write_timer_handler (net/ipv4/tcp_timer.c:378 net/ipv4/tcp_timer.c:624 net/ipv4/tcp_timer.c:594) Read of size 1 at addr ffff888052b65e0d by task syzrepro/18091

CPU: 0 PID: 18091 Comm: syzrepro Tainted: G W 6.3.0-rc4-01174-gb5d54eb5899a #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.amzn2022.0.1 04/01/2014 Call Trace: <IRQ> dump_stack_lvl (lib/dump_stack.c:107) print_report (mm/kasan/report.c:320 mm/kasan/report.c:430) kasan_report (mm/kasan/report.c:538) tcp_write_timer_handler (net/ipv4/tcp_timer.c:378 net/ipv4/tcp_timer.c:624 net/ipv4/tcp_timer.c:594) tcp_write_timer (./include/linux/spinlock.h:390 net/ipv4/tcp_timer.c:643) call_timer_fn (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/timer.h:127 kernel/time/timer.c:1701) __run_timers.part.0 (kernel/time/timer.c:1752 kernel/time/timer.c:2022) run_timer_softirq (kernel/time/timer.c:2037) __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:572) __irq_exit_rcu (kernel/softirq.c:445 kernel/softirq.c:650) irq_exit_rcu (kernel/softirq.c:664) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1107 (discriminator 14)) </IRQ>(CVE-2023-53781)

In the Linux kernel, the following vulnerability has been resolved:

ip6_vti: fix slab-use-after-free in decode_session6

When ipv6_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ipv6_vti device sends IPv6 packets.

The stack information is as follows: BUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890 Read of size 1 at addr ffff88802e08edc2 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0xd9/0x150 print_address_description.constprop.0+0x2c/0x3c0 kasan_report+0x11d/0x130 decode_session6+0x103f/0x1890 __xfrm_decode_session+0x54/0xb0 vti6_tnl_xmit+0x3e6/0x1ee0 dev_hard_start_xmit+0x187/0x700 sch_direct_xmit+0x1a3/0xc30 __qdisc_run+0x510/0x17a0 __dev_queue_xmit+0x2215/0x3b10 neigh_connected_output+0x3c2/0x550 ip6_finish_output2+0x55a/0x1550 ip6_finish_output+0x6b9/0x1270 ip6_output+0x1f1/0x540 ndisc_send_skb+0xa63/0x1890 ndisc_send_rs+0x132/0x6f0 addrconf_rs_timer+0x3f1/0x870 call_timer_fn+0x1a0/0x580 expire_timers+0x29b/0x4b0 run_timer_softirq+0x326/0x910 __do_softirq+0x1d4/0x905 irq_exit_rcu+0xb7/0x120 sysvec_apic_timer_interrupt+0x97/0xc0 </IRQ> Allocated by task 9176: kasan_save_stack+0x22/0x40 kasan_set_track+0x25/0x30 __kasan_slab_alloc+0x7f/0x90 kmem_cache_alloc_node+0x1cd/0x410 kmalloc_reserve+0x165/0x270 __alloc_skb+0x129/0x330 netlink_sendmsg+0x9b1/0xe30 sock_sendmsg+0xde/0x190 ____sys_sendmsg+0x739/0x920 ___sys_sendmsg+0x110/0x1b0 __sys_sendmsg+0xf7/0x1c0 do_syscall_64+0x39/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 9176: kasan_save_stack+0x22/0x40 kasan_set_track+0x25/0x30 kasan_save_free_info+0x2b/0x40 ____kasan_slab_free+0x160/0x1c0 slab_free_freelist_hook+0x11b/0x220 kmem_cache_free+0xf0/0x490 skb_free_head+0x17f/0x1b0 skb_release_data+0x59c/0x850 consume_skb+0xd2/0x170 netlink_unicast+0x54f/0x7f0 netlink_sendmsg+0x926/0xe30 sock_sendmsg+0xde/0x190 ____sys_sendmsg+0x739/0x920 ___sys_sendmsg+0x110/0x1b0 __sys_sendmsg+0xf7/0x1c0 do_syscall_64+0x39/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88802e08ed00 which belongs to the cache skbuff_small_head of size 640 The buggy address is located 194 bytes inside of freed 640-byte region [ffff88802e08ed00, ffff88802e08ef80)

As commit f855691975bb ("xfrm6: Fix the nexthdr offset in _decode_session6.") showed, xfrm_decode_session was originally intended only for the receive path. IP6CB(skb)->nhoff is not set during transmission. Therefore, set the cb field in the skb to 0 before sending packets.(CVE-2023-53821)

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix to do sanity check on direct node in truncate_dnode()

syzbot reports below bug:

BUG: KASAN: slab-use-after-free in f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574 Read of size 4 at addr ffff88802a25c000 by task syz-executor148/5000

CPU: 1 PID: 5000 Comm: syz-executor148 Not tainted 6.4.0-rc7-syzkaller-00041-ge660abd551f1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:572 f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574 truncate_dnode+0x229/0x2e0 fs/f2fs/node.c:944 f2fs_truncate_inode_blocks+0x64b/0xde0 fs/f2fs/node.c:1154 f2fs_do_truncate_blocks+0x4ac/0xf30 fs/f2fs/file.c:721 f2fs_truncate_blocks+0x7b/0x300 fs/f2fs/file.c:749 f2fs_truncate.part.0+0x4a5/0x630 fs/f2fs/file.c:799 f2fs_truncate include/linux/fs.h:825 [inline] f2fs_setattr+0x1738/0x2090 fs/f2fs/file.c:1006 notify_change+0xb2c/0x1180 fs/attr.c:483 do_truncate+0x143/0x200 fs/open.c:66 handle_truncate fs/namei.c:3295 [inline] do_open fs/namei.c:3640 [inline] path_openat+0x2083/0x2750 fs/namei.c:3791 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_creat fs/open.c:1448 [inline] __se_sys_creat fs/open.c:1442 [inline] __x64_sys_creat+0xcd/0x120 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The root cause is, inodeA references inodeB via inodeB's ino, once inodeA is truncated, it calls truncate_dnode() to truncate data blocks in inodeB's node page, it traverse mapping data from node->i.i_addr[0] to node->i.i_addr[ADDRS_PER_BLOCK() - 1], result in out-of-boundary access.

This patch fixes to add sanity check on dnode page in truncate_dnode(), so that, it can help to avoid triggering such issue, and once it encounters such issue, it will record newly introduced ERROR_INVALID_NODE_REFERENCE error into superblock, later fsck can detect such issue and try repairing.

Also, it removes f2fs_truncate_data_blocks() for cleanup due to the function has only one caller, and uses f2fs_truncate_data_blocks_range() instead.(CVE-2023-53846)

In the Linux kernel, the following vulnerability has been resolved:

ext4: correct grp validation in ext4_mb_good_group

Group corruption check will access memory of grp and will trigger kernel crash if grp is NULL. So do NULL check before corruption check.(CVE-2023-53861)

In the Linux kernel, the following vulnerability has been resolved:

qed: Don't collect too many protection override GRC elements

In the protection override dump path, the firmware can return far too many GRC elements, resulting in attempting to write past the end of the previously-kmalloc'ed dump buffer.

This will result in a kernel panic with reason:

BUG: unable to handle kernel paging request at ADDRESS

where "ADDRESS" is just past the end of the protection override dump buffer. The start address of the buffer is: p_hwfn->cdev->dbg_features[DBG_FEATURE_PROTECTION_OVERRIDE].dump_buf and the size of the buffer is buf_size in the same data structure.

The panic can be arrived at from either the qede Ethernet driver path:

[exception RIP: qed_grc_dump_addr_range+0x108]

qed_protection_override_dump at ffffffffc02662ed [qed] qed_dbg_protection_override_dump at ffffffffc0267792 [qed] qed_dbg_feature at ffffffffc026aa8f [qed] qed_dbg_all_data at ffffffffc026b211 [qed] qed_fw_fatal_reporter_dump at ffffffffc027298a [qed] devlink_health_do_dump at ffffffff82497f61 devlink_health_report at ffffffff8249cf29 qed_report_fatal_error at ffffffffc0272baf [qed] qede_sp_task at ffffffffc045ed32 [qede] process_one_work at ffffffff81d19783

or the qedf storage driver path:

[exception RIP: qed_grc_dump_addr_range+0x108]

qed_protection_override_dump at ffffffffc068b2ed [qed] qed_dbg_protection_override_dump at ffffffffc068c792 [qed] qed_dbg_feature at ffffffffc068fa8f [qed] qed_dbg_all_data at ffffffffc0690211 [qed] qed_fw_fatal_reporter_dump at ffffffffc069798a [qed] devlink_health_do_dump at ffffffff8aa95e51 devlink_health_report at ffffffff8aa9ae19 qed_report_fatal_error at ffffffffc0697baf [qed] qed_hw_err_notify at ffffffffc06d32d7 [qed] qed_spq_post at ffffffffc06b1011 [qed] qed_fcoe_destroy_conn at ffffffffc06b2e91 [qed] qedf_cleanup_fcport at ffffffffc05e7597 [qedf] qedf_rport_event_handler at ffffffffc05e7bf7 [qedf] fc_rport_work at ffffffffc02da715 [libfc] process_one_work at ffffffff8a319663

Resolve this by clamping the firmware's return value to the maximum number of legal elements the firmware should return.(CVE-2025-39949)

In the Linux kernel, the following vulnerability has been resolved:

i40e: fix validation of VF state in get resources

VF state I40E_VF_STATE_ACTIVE is not the only state in which VF is actually active so it should not be used to determine if a VF is allowed to obtain resources.

Use I40E_VF_STATE_RESOURCES_LOADED that is set only in i40e_vc_get_vf_resources_msg() and cleared during reset.(CVE-2025-39969)

In the Linux kernel, the following vulnerability has been resolved:

i40e: fix input validation logic for action_meta

Fix condition to check 'greater or equal' to prevent OOB dereference.(CVE-2025-39970)

In the Linux kernel, the following vulnerability has been resolved:

Squashfs: reject negative file sizes in squashfs_read_inode()

Syskaller reports a "WARNING in ovl_copy_up_file" in overlayfs.

This warning is ultimately caused because the underlying Squashfs file system returns a file with a negative file size.

This commit checks for a negative file size and returns EINVAL.

[(CVE-2025-40200)

In the Linux kernel, the following vulnerability has been resolved:

x86/fpu: Ensure XFD state on signal delivery

Sean reported [1] the following splat when running KVM tests:

WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70 Call Trace: <TASK> fpu__clear_user_states+0x9c/0x100 arch_do_signal_or_restart+0x142/0x210 exit_to_user_mode_loop+0x55/0x100 do_syscall_64+0x205/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53

Chao further identified [2] a reproducible scenario involving signal delivery: a non-AMX task is preempted by an AMX-enabled task which modifies the XFD MSR.

When the non-AMX task resumes and reloads XSTATE with init values, a warning is triggered due to a mismatch between fpstate::xfd and the CPU's current XFD state. fpu__clear_user_states() does not currently re-synchronize the XFD state after such preemption.

Invoke xfd_update_state() which detects and corrects the mismatch if there is a dynamic feature.

This also benefits the sigreturn path, as fpu__restore_sig() may call fpu__clear_user_states() when the sigframe is inaccessible.

dhansen: minor changelog munging

In the Linux kernel, the following vulnerability has been resolved:

isdn: mISDN: hfcsusb: fix memory leak in hfcsusb_probe()

In hfcsusb_probe(), the memory allocated for ctrl_urb gets leaked when setup_instance() fails with an error code. Fix that by freeing the urb before freeing the hw structure. Also change the error paths to use the goto ladder style.

Compile tested only. Issue found using a prototype static analysis tool.(CVE-2025-68734)

In the Linux kernel, the following vulnerability has been resolved:

scsi: qla2xxx: Clear cmds after chip reset

Commit aefed3e5548f ("scsi: qla2xxx: target: Fix offline port handling and host reset handling") caused two problems:

1. Commands sent to FW, after chip reset got stuck and never freed as FW is not going to respond to them anymore.

2. BUG_ON(cmd->sg_mapped) in qlt_free_cmd(). Commit 26f9ce53817a ("scsi: qla2xxx: Fix missed DMA unmap for aborted commands") attempted to fix this, but introduced another bug under different circumstances when two different CPUs were racing to call qlt_unmap_sg() at the same time: BUG_ON(!valid_dma_direction(dir)) in dma_unmap_sg_attrs().

So revert "scsi: qla2xxx: Fix missed DMA unmap for aborted commands" and partially revert "scsi: qla2xxx: target: Fix offline port handling and host reset handling" at __qla2x00_abort_all_cmds.(CVE-2025-68745)