In the Linux kernel, the following vulnerability has been resolved: USB: core: Fix hang in usb_kill_urb by adding memory barriers The syzbot fuzzer has identified a bug in which processes hang waiting for usb_kill_urb() to return. It turns out the issue is not unlinking the URB; that works just fine. Rather, the problem arises when the wakeup notification that the URB has completed is not received. The reason is memory-access ordering on SMP systems. In outline form, usb_kill_urb() and __usb_hcd_giveback_urb() operating concurrently on different CPUs perform the following actions: CPU 0 CPU 1 ---------------------------- --------------------------------- usb_kill_urb(): __usb_hcd_giveback_urb(): ... ... atomic_inc(&urb->reject); atomic_dec(&urb->use_count); ... ... wait_event(usb_kill_urb_queue, atomic_read(&urb->use_count) == 0); if (atomic_read(&urb->reject)) wake_up(&usb_kill_urb_queue); Confining your attention to urb->reject and urb->use_count, you can see that the overall pattern of accesses on CPU 0 is: write urb->reject, then read urb->use_count; whereas the overall pattern of accesses on CPU 1 is: write urb->use_count, then read urb->reject. This pattern is referred to in memory-model circles as SB (for "Store Buffering"), and it is well known that without suitable enforcement of the desired order of accesses -- in the form of memory barriers -- it is entirely possible for one or both CPUs to execute their reads ahead of their writes. The end result will be that sometimes CPU 0 sees the old un-decremented value of urb->use_count while CPU 1 sees the old un-incremented value of urb->reject. Consequently CPU 0 ends up on the wait queue and never gets woken up, leading to the observed hang in usb_kill_urb(). The same pattern of accesses occurs in usb_poison_urb() and the failure pathway of usb_hcd_submit_urb(). The problem is fixed by adding suitable memory barriers. To provide proper memory-access ordering in the SB pattern, a full barrier is required on both CPUs. The atomic_inc() and atomic_dec() accesses themselves don't provide any memory ordering, but since they are present, we can use the optimized smp_mb__after_atomic() memory barrier in the various routines to obtain the desired effect. This patch adds the necessary memory barriers.

In the Linux kernel, the following vulnerability has been resolved: rpmsg: char: Fix race between the release of rpmsg_ctrldev and cdev struct rpmsg_ctrldev contains a struct cdev. The current code frees the rpmsg_ctrldev struct in rpmsg_ctrldev_release_device(), but the cdev is a managed object, therefore its release is not predictable and the rpmsg_ctrldev could be freed before the cdev is entirely released, as in the backtrace below. [ 93.625603] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x7c [ 93.636115] WARNING: CPU: 0 PID: 12 at lib/debugobjects.c:488 debug_print_object+0x13c/0x1b0 [ 93.644799] Modules linked in: veth xt_cgroup xt_MASQUERADE rfcomm algif_hash algif_skcipher af_alg uinput ip6table_nat fuse uvcvideo videobuf2_vmalloc venus_enc venus_dec videobuf2_dma_contig hci_uart btandroid btqca snd_soc_rt5682_i2c bluetooth qcom_spmi_temp_alarm snd_soc_rt5682v [ 93.715175] CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G B 5.4.163-lockdep #26 [ 93.723855] Hardware name: Google Lazor (rev3 - 8) with LTE (DT) [ 93.730055] Workqueue: events kobject_delayed_cleanup [ 93.735271] pstate: 60c00009 (nZCv daif +PAN +UAO) [ 93.740216] pc : debug_print_object+0x13c/0x1b0 [ 93.744890] lr : debug_print_object+0x13c/0x1b0 [ 93.749555] sp : ffffffacf5bc7940 [ 93.752978] x29: ffffffacf5bc7940 x28: dfffffd000000000 [ 93.758448] x27: ffffffacdb11a800 x26: dfffffd000000000 [ 93.763916] x25: ffffffd0734f856c x24: dfffffd000000000 [ 93.769389] x23: 0000000000000000 x22: ffffffd0733c35b0 [ 93.774860] x21: ffffffd0751994a0 x20: ffffffd075ec27c0 [ 93.780338] x19: ffffffd075199100 x18: 00000000000276e0 [ 93.785814] x17: 0000000000000000 x16: dfffffd000000000 [ 93.791291] x15: ffffffffffffffff x14: 6e6968207473696c [ 93.796768] x13: 0000000000000000 x12: ffffffd075e2b000 [ 93.802244] x11: 0000000000000001 x10: 0000000000000000 [ 93.807723] x9 : d13400dff1921900 x8 : d13400dff1921900 [ 93.813200] x7 : 0000000000000000 x6 : 0000000000000000 [ 93.818676] x5 : 0000000000000080 x4 : 0000000000000000 [ 93.824152] x3 : ffffffd0732a0fa4 x2 : 0000000000000001 [ 93.829628] x1 : ffffffacf5bc7580 x0 : 0000000000000061 [ 93.835104] Call trace: [ 93.837644] debug_print_object+0x13c/0x1b0 [ 93.841963] __debug_check_no_obj_freed+0x25c/0x3c0 [ 93.846987] debug_check_no_obj_freed+0x18/0x20 [ 93.851669] slab_free_freelist_hook+0xbc/0x1e4 [ 93.856346] kfree+0xfc/0x2f4 [ 93.859416] rpmsg_ctrldev_release_device+0x78/0xb8 [ 93.864445] device_release+0x84/0x168 [ 93.868310] kobject_cleanup+0x12c/0x298 [ 93.872356] kobject_delayed_cleanup+0x10/0x18 [ 93.876948] process_one_work+0x578/0x92c [ 93.881086] worker_thread+0x804/0xcf8 [ 93.884963] kthread+0x2a8/0x314 [ 93.888303] ret_from_fork+0x10/0x18 The cdev_device_add/del() API was created to address this issue (see commit '233ed09d7fda ("chardev: add helper function to register char devs with a struct device")'), use it instead of cdev add/del().

In the Linux kernel, the following vulnerability has been resolved: scsi: bnx2fc: Flush destroy_work queue before calling bnx2fc_interface_put() The bnx2fc_destroy() functions are removing the interface before calling destroy_work. This results multiple WARNings from sysfs_remove_group() as the controller rport device attributes are removed too early. Replace the fcoe_port's destroy_work queue. It's not needed. The problem is easily reproducible with the following steps. Example: $ dmesg -w & $ systemctl enable --now fcoe $ fipvlan -s -c ens2f1 $ fcoeadm -d ens2f1.802 [ 583.464488] host2: libfc: Link down on port (7500a1) [ 583.472651] bnx2fc: 7500a1 - rport not created Yet!! [ 583.490468] ------------[ cut here ]------------ [ 583.538725] sysfs group 'power' not found for kobject 'rport-2:0-0' [ 583.568814] WARNING: CPU: 3 PID: 192 at fs/sysfs/group.c:279 sysfs_remove_group+0x6f/0x80 [ 583.607130] Modules linked in: dm_service_time 8021q garp mrp stp llc bnx2fc cnic uio rpcsec_gss_krb5 auth_rpcgss nfsv4 ... [ 583.942994] CPU: 3 PID: 192 Comm: kworker/3:2 Kdump: loaded Not tainted 5.14.0-39.el9.x86_64 #1 [ 583.984105] Hardware name: HP ProLiant DL120 G7, BIOS J01 07/01/2013 [ 584.016535] Workqueue: fc_wq_2 fc_rport_final_delete [scsi_transport_fc] [ 584.050691] RIP: 0010:sysfs_remove_group+0x6f/0x80 [ 584.074725] Code: ff 5b 48 89 ef 5d 41 5c e9 ee c0 ff ff 48 89 ef e8 f6 b8 ff ff eb d1 49 8b 14 24 48 8b 33 48 c7 c7 ... [ 584.162586] RSP: 0018:ffffb567c15afdc0 EFLAGS: 00010282 [ 584.188225] RAX: 0000000000000000 RBX: ffffffff8eec4220 RCX: 0000000000000000 [ 584.221053] RDX: ffff8c1586ce84c0 RSI: ffff8c1586cd7cc0 RDI: ffff8c1586cd7cc0 [ 584.255089] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffb567c15afc00 [ 584.287954] R10: ffffb567c15afbf8 R11: ffffffff8fbe7f28 R12: ffff8c1486326400 [ 584.322356] R13: ffff8c1486326480 R14: ffff8c1483a4a000 R15: 0000000000000004 [ 584.355379] FS: 0000000000000000(0000) GS:ffff8c1586cc0000(0000) knlGS:0000000000000000 [ 584.394419] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 584.421123] CR2: 00007fe95a6f7840 CR3: 0000000107674002 CR4: 00000000000606e0 [ 584.454888] Call Trace: [ 584.466108] device_del+0xb2/0x3e0 [ 584.481701] device_unregister+0x13/0x60 [ 584.501306] bsg_unregister_queue+0x5b/0x80 [ 584.522029] bsg_remove_queue+0x1c/0x40 [ 584.541884] fc_rport_final_delete+0xf3/0x1d0 [scsi_transport_fc] [ 584.573823] process_one_work+0x1e3/0x3b0 [ 584.592396] worker_thread+0x50/0x3b0 [ 584.609256] ? rescuer_thread+0x370/0x370 [ 584.628877] kthread+0x149/0x170 [ 584.643673] ? set_kthread_struct+0x40/0x40 [ 584.662909] ret_from_fork+0x22/0x30 [ 584.680002] ---[ end trace 53575ecefa942ece ]---

In the Linux kernel, the following vulnerability has been resolved: net: fix information leakage in /proc/net/ptype In one net namespace, after creating a packet socket without binding it to a device, users in other net namespaces can observe the new `packet_type` added by this packet socket by reading `/proc/net/ptype` file. This is minor information leakage as packet socket is namespace aware. Add a net pointer in `packet_type` to keep the net namespace of of corresponding packet socket. In `ptype_seq_show`, this net pointer must be checked when it is not NULL.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dsi: invalid parameter check in msm_dsi_phy_enable The function performs a check on the "phy" input parameter, however, it is used before the check. Initialize the "dev" variable after the sanity check to avoid a possible NULL pointer dereference. Addresses-Coverity-ID: 1493860 ("Null pointer dereference")

In the Linux kernel, the following vulnerability has been resolved: powerpc64/bpf: Limit 'ldbrx' to processors compliant with ISA v2.06 Johan reported the below crash with test_bpf on ppc64 e5500: test_bpf: #296 ALU_END_FROM_LE 64: 0x0123456789abcdef -> 0x67452301 jited:1 Oops: Exception in kernel mode, sig: 4 [#1] BE PAGE_SIZE=4K SMP NR_CPUS=24 QEMU e500 Modules linked in: test_bpf(+) CPU: 0 PID: 76 Comm: insmod Not tainted 5.14.0-03771-g98c2059e008a-dirty #1 NIP: 8000000000061c3c LR: 80000000006dea64 CTR: 8000000000061c18 REGS: c0000000032d3420 TRAP: 0700 Not tainted (5.14.0-03771-g98c2059e008a-dirty) MSR: 0000000080089000 <EE,ME> CR: 88002822 XER: 20000000 IRQMASK: 0 <...> NIP [8000000000061c3c] 0x8000000000061c3c LR [80000000006dea64] .__run_one+0x104/0x17c [test_bpf] Call Trace: .__run_one+0x60/0x17c [test_bpf] (unreliable) .test_bpf_init+0x6a8/0xdc8 [test_bpf] .do_one_initcall+0x6c/0x28c .do_init_module+0x68/0x28c .load_module+0x2460/0x2abc .__do_sys_init_module+0x120/0x18c .system_call_exception+0x110/0x1b8 system_call_common+0xf0/0x210 --- interrupt: c00 at 0x101d0acc <...> ---[ end trace 47b2bf19090bb3d0 ]--- Illegal instruction The illegal instruction turned out to be 'ldbrx' emitted for BPF_FROM_[L|B]E, which was only introduced in ISA v2.06. Guard use of the same and implement an alternative approach for older processors.

In the Linux kernel, the following vulnerability has been resolved: phylib: fix potential use-after-free Commit bafbdd527d56 ("phylib: Add device reset GPIO support") added call to phy_device_reset(phydev) after the put_device() call in phy_detach(). The comment before the put_device() call says that the phydev might go away with put_device(). Fix potential use-after-free by calling phy_device_reset() before put_device().

In the Linux kernel, the following vulnerability has been resolved: block: fix memory leak in disk_register_independent_access_ranges kobject_init_and_add() takes reference even when it fails. According to the doc of kobject_init_and_add() If this function returns an error, kobject_put() must be called to properly clean up the memory associated with the object. Fix this issue by adding kobject_put(). Callback function blk_ia_ranges_sysfs_release() in kobject_put() can handle the pointer "iars" properly.

In the Linux kernel, the following vulnerability has been resolved: powerpc/perf: Fix power_pmu_disable to call clear_pmi_irq_pending only if PMI is pending Running selftest with CONFIG_PPC_IRQ_SOFT_MASK_DEBUG enabled in kernel triggered below warning: [ 172.851380] ------------[ cut here ]------------ [ 172.851391] WARNING: CPU: 8 PID: 2901 at arch/powerpc/include/asm/hw_irq.h:246 power_pmu_disable+0x270/0x280 [ 172.851402] Modules linked in: dm_mod bonding nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables rfkill nfnetlink sunrpc xfs libcrc32c pseries_rng xts vmx_crypto uio_pdrv_genirq uio sch_fq_codel ip_tables ext4 mbcache jbd2 sd_mod t10_pi sg ibmvscsi ibmveth scsi_transport_srp fuse [ 172.851442] CPU: 8 PID: 2901 Comm: lost_exception_ Not tainted 5.16.0-rc5-03218-g798527287598 #2 [ 172.851451] NIP: c00000000013d600 LR: c00000000013d5a4 CTR: c00000000013b180 [ 172.851458] REGS: c000000017687860 TRAP: 0700 Not tainted (5.16.0-rc5-03218-g798527287598) [ 172.851465] MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 48004884 XER: 20040000 [ 172.851482] CFAR: c00000000013d5b4 IRQMASK: 1 [ 172.851482] GPR00: c00000000013d5a4 c000000017687b00 c000000002a10600 0000000000000004 [ 172.851482] GPR04: 0000000082004000 c0000008ba08f0a8 0000000000000000 00000008b7ed0000 [ 172.851482] GPR08: 00000000446194f6 0000000000008000 c00000000013b118 c000000000d58e68 [ 172.851482] GPR12: c00000000013d390 c00000001ec54a80 0000000000000000 0000000000000000 [ 172.851482] GPR16: 0000000000000000 0000000000000000 c000000015d5c708 c0000000025396d0 [ 172.851482] GPR20: 0000000000000000 0000000000000000 c00000000a3bbf40 0000000000000003 [ 172.851482] GPR24: 0000000000000000 c0000008ba097400 c0000000161e0d00 c00000000a3bb600 [ 172.851482] GPR28: c000000015d5c700 0000000000000001 0000000082384090 c0000008ba0020d8 [ 172.851549] NIP [c00000000013d600] power_pmu_disable+0x270/0x280 [ 172.851557] LR [c00000000013d5a4] power_pmu_disable+0x214/0x280 [ 172.851565] Call Trace: [ 172.851568] [c000000017687b00] [c00000000013d5a4] power_pmu_disable+0x214/0x280 (unreliable) [ 172.851579] [c000000017687b40] [c0000000003403ac] perf_pmu_disable+0x4c/0x60 [ 172.851588] [c000000017687b60] [c0000000003445e4] __perf_event_task_sched_out+0x1d4/0x660 [ 172.851596] [c000000017687c50] [c000000000d1175c] __schedule+0xbcc/0x12a0 [ 172.851602] [c000000017687d60] [c000000000d11ea8] schedule+0x78/0x140 [ 172.851608] [c000000017687d90] [c0000000001a8080] sys_sched_yield+0x20/0x40 [ 172.851615] [c000000017687db0] [c0000000000334dc] system_call_exception+0x18c/0x380 [ 172.851622] [c000000017687e10] [c00000000000c74c] system_call_common+0xec/0x268 The warning indicates that MSR_EE being set(interrupt enabled) when there was an overflown PMC detected. This could happen in power_pmu_disable since it runs under interrupt soft disable condition ( local_irq_save ) and not with interrupts hard disabled. commit 2c9ac51b850d ("powerpc/perf: Fix PMU callbacks to clear pending PMI before resetting an overflown PMC") intended to clear PMI pending bit in Paca when disabling the PMU. It could happen that PMC gets overflown while code is in power_pmu_disable callback function. Hence add a check to see if PMI pending bit is set in Paca before clearing it via clear_pmi_pending.

In the Linux kernel, the following vulnerability has been resolved: net/smc: Transitional solution for clcsock race issue We encountered a crash in smc_setsockopt() and it is caused by accessing smc->clcsock after clcsock was released. BUG: kernel NULL pointer dereference, address: 0000000000000020 #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: 1 PID: 50309 Comm: nginx Kdump: loaded Tainted: G E 5.16.0-rc4+ #53 RIP: 0010:smc_setsockopt+0x59/0x280 [smc] Call Trace: <TASK> __sys_setsockopt+0xfc/0x190 __x64_sys_setsockopt+0x20/0x30 do_syscall_64+0x34/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f16ba83918e </TASK> This patch tries to fix it by holding clcsock_release_lock and checking whether clcsock has already been released before access. In case that a crash of the same reason happens in smc_getsockopt() or smc_switch_to_fallback(), this patch also checkes smc->clcsock in them too. And the caller of smc_switch_to_fallback() will identify whether fallback succeeds according to the return value.

In the Linux kernel, the following vulnerability has been resolved: hwmon: (nct6775) Fix crash in clear_caseopen Paweł Marciniak reports the following crash, observed when clearing the chassis intrusion alarm. BUG: kernel NULL pointer dereference, address: 0000000000000028 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 3 PID: 4815 Comm: bash Tainted: G S 5.16.2-200.fc35.x86_64 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z97 Extreme4, BIOS P2.60A 05/03/2018 RIP: 0010:clear_caseopen+0x5a/0x120 [nct6775] Code: 68 70 e8 e9 32 b1 e3 85 c0 0f 85 d2 00 00 00 48 83 7c 24 ... RSP: 0018:ffffabcb02803dd8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 RDX: ffff8e8808192880 RSI: 0000000000000000 RDI: ffff8e87c7509a68 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000000000a R10: 000000000000000a R11: f000000000000000 R12: 000000000000001f R13: ffff8e87c7509828 R14: ffff8e87c7509a68 R15: ffff8e88494527a0 FS: 00007f4db9151740(0000) GS:ffff8e8ebfec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000028 CR3: 0000000166b66001 CR4: 00000000001706e0 Call Trace: <TASK> kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x10b/0x180 vfs_write+0x209/0x2a0 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae The problem is that the device passed to clear_caseopen() is the hwmon device, not the platform device, and the platform data is not set in the hwmon device. Store the pointer to sio_data in struct nct6775_data and get if from there if needed.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: invalid parameter check in dpu_setup_dspp_pcc The function performs a check on the "ctx" input parameter, however, it is used before the check. Initialize the "base" variable after the sanity check to avoid a possible NULL pointer dereference. Addresses-Coverity-ID: 1493866 ("Null pointer dereference")

In the Linux kernel, the following vulnerability has been resolved: net: bridge: vlan: fix memory leak in __allowed_ingress When using per-vlan state, if vlan snooping and stats are disabled, untagged or priority-tagged ingress frame will go to check pvid state. If the port state is forwarding and the pvid state is not learning/forwarding, untagged or priority-tagged frame will be dropped but skb memory is not freed. Should free skb when __allowed_ingress returns false.

In the Linux kernel, the following vulnerability has been resolved: block: Fix wrong offset in bio_truncate() bio_truncate() clears the buffer outside of last block of bdev, however current bio_truncate() is using the wrong offset of page. So it can return the uninitialized data. This happened when both of truncated/corrupted FS and userspace (via bdev) are trying to read the last of bdev.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix handling of wrong devices during bond netevent Current implementation of bond netevent handler only check if the handled netdev is VF representor and it missing a check if the VF representor is on the same phys device of the bond handling the netevent. Fix by adding the missing check and optimizing the check if the netdev is VF representor so it will not access uninitialized private data and crashes. BUG: kernel NULL pointer dereference, address: 000000000000036c PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI Workqueue: eth3bond0 bond_mii_monitor [bonding] RIP: 0010:mlx5e_is_uplink_rep+0xc/0x50 [mlx5_core] RSP: 0018:ffff88812d69fd60 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8881cf800000 RCX: 0000000000000000 RDX: ffff88812d69fe10 RSI: 000000000000001b RDI: ffff8881cf800880 RBP: ffff8881cf800000 R08: 00000445cabccf2b R09: 0000000000000008 R10: 0000000000000004 R11: 0000000000000008 R12: ffff88812d69fe10 R13: 00000000fffffffe R14: ffff88820c0f9000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88846fb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000036c CR3: 0000000103d80006 CR4: 0000000000370ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mlx5e_eswitch_uplink_rep+0x31/0x40 [mlx5_core] mlx5e_rep_is_lag_netdev+0x94/0xc0 [mlx5_core] mlx5e_rep_esw_bond_netevent+0xeb/0x3d0 [mlx5_core] raw_notifier_call_chain+0x41/0x60 call_netdevice_notifiers_info+0x34/0x80 netdev_lower_state_changed+0x4e/0xa0 bond_mii_monitor+0x56b/0x640 [bonding] process_one_work+0x1b9/0x390 worker_thread+0x4d/0x3d0 ? rescuer_thread+0x350/0x350 kthread+0x124/0x150 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x1f/0x30

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Use del_timer_sync in fw reset flow of halting poll Substitute del_timer() with del_timer_sync() in fw reset polling deactivation flow, in order to prevent a race condition which occurs when del_timer() is called and timer is deactivated while another process is handling the timer interrupt. A situation that led to the following call trace: RIP: 0010:run_timer_softirq+0x137/0x420 <IRQ> recalibrate_cpu_khz+0x10/0x10 ktime_get+0x3e/0xa0 ? sched_clock_cpu+0xb/0xc0 __do_softirq+0xf5/0x2ea irq_exit_rcu+0xc1/0xf0 sysvec_apic_timer_interrupt+0x9e/0xc0 asm_sysvec_apic_timer_interrupt+0x12/0x20 </IRQ>

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Avoid field-overflowing memcpy() In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. Use flexible arrays instead of zero-element arrays (which look like they are always overflowing) and split the cross-field memcpy() into two halves that can be appropriately bounds-checked by the compiler. We were doing: #define ETH_HLEN 14 #define VLAN_HLEN 4 ... #define MLX5E_XDP_MIN_INLINE (ETH_HLEN + VLAN_HLEN) ... struct mlx5e_tx_wqe *wqe = mlx5_wq_cyc_get_wqe(wq, pi); ... struct mlx5_wqe_eth_seg *eseg = &wqe->eth; struct mlx5_wqe_data_seg *dseg = wqe->data; ... memcpy(eseg->inline_hdr.start, xdptxd->data, MLX5E_XDP_MIN_INLINE); target is wqe->eth.inline_hdr.start (which the compiler sees as being 2 bytes in size), but copying 18, intending to write across start (really vlan_tci, 2 bytes). The remaining 16 bytes get written into wqe->data[0], covering byte_count (4 bytes), lkey (4 bytes), and addr (8 bytes). struct mlx5e_tx_wqe { struct mlx5_wqe_ctrl_seg ctrl; /* 0 16 */ struct mlx5_wqe_eth_seg eth; /* 16 16 */ struct mlx5_wqe_data_seg data[]; /* 32 0 */ /* size: 32, cachelines: 1, members: 3 */ /* last cacheline: 32 bytes */ }; struct mlx5_wqe_eth_seg { u8 swp_outer_l4_offset; /* 0 1 */ u8 swp_outer_l3_offset; /* 1 1 */ u8 swp_inner_l4_offset; /* 2 1 */ u8 swp_inner_l3_offset; /* 3 1 */ u8 cs_flags; /* 4 1 */ u8 swp_flags; /* 5 1 */ __be16 mss; /* 6 2 */ __be32 flow_table_metadata; /* 8 4 */ union { struct { __be16 sz; /* 12 2 */ u8 start[2]; /* 14 2 */ } inline_hdr; /* 12 4 */ struct { __be16 type; /* 12 2 */ __be16 vlan_tci; /* 14 2 */ } insert; /* 12 4 */ __be32 trailer; /* 12 4 */ }; /* 12 4 */ /* size: 16, cachelines: 1, members: 9 */ /* last cacheline: 16 bytes */ }; struct mlx5_wqe_data_seg { __be32 byte_count; /* 0 4 */ __be32 lkey; /* 4 4 */ __be64 addr; /* 8 8 */ /* size: 16, cachelines: 1, members: 3 */ /* last cacheline: 16 bytes */ }; So, split the memcpy() so the compiler can reason about the buffer sizes. "pahole" shows no size nor member offset changes to struct mlx5e_tx_wqe nor struct mlx5e_umr_wqe. "objdump -d" shows no meaningful object code changes (i.e. only source line number induced differences and optimizations).

In the Linux kernel, the following vulnerability has been resolved: net: amd-xgbe: Fix skb data length underflow There will be BUG_ON() triggered in include/linux/skbuff.h leading to intermittent kernel panic, when the skb length underflow is detected. Fix this by dropping the packet if such length underflows are seen because of inconsistencies in the hardware descriptors.

In the Linux kernel, the following vulnerability has been resolved: rtnetlink: make sure to refresh master_dev/m_ops in __rtnl_newlink() While looking at one unrelated syzbot bug, I found the replay logic in __rtnl_newlink() to potentially trigger use-after-free. It is better to clear master_dev and m_ops inside the loop, in case we have to replay it.

In the Linux kernel, the following vulnerability has been resolved: ovl: fix NULL pointer dereference in copy up warning This patch is fixing a NULL pointer dereference to get a recently introduced warning message working.