In the Linux kernel, the following vulnerability has been resolved: media: cx231xx: set device_caps for 417 The video_device for the MPEG encoder did not set device_caps. Add this, otherwise the video device can't be registered (you get a WARN_ON instead). Not seen before since currently 417 support is disabled, but I found this while experimenting with it.
In the Linux kernel, the following vulnerability has been resolved: iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_tagged_fifo Prevent st_lsm6dsx_read_tagged_fifo from falling in an infinite loop in case pattern_len is equal to zero and the device FIFO is not empty.
In the Linux kernel, the following vulnerability has been resolved: wifi: wl1251: fix memory leak in wl1251_tx_work The skb dequeued from tx_queue is lost when wl1251_ps_elp_wakeup fails with a -ETIMEDOUT error. Fix that by queueing the skb back to tx_queue.
In the Linux kernel, the following vulnerability has been resolved: padata: do not leak refcount in reorder_work A recent patch that addressed a UAF introduced a reference count leak: the parallel_data refcount is incremented unconditionally, regardless of the return value of queue_work(). If the work item is already queued, the incremented refcount is never decremented. Fix this by checking the return value of queue_work() and decrementing the refcount when necessary. Resolves: Unreferenced object 0xffff9d9f421e3d80 (size 192): comm "cryptomgr_probe", pid 157, jiffies 4294694003 hex dump (first 32 bytes): 80 8b cf 41 9f 9d ff ff b8 97 e0 89 ff ff ff ff ...A............ d0 97 e0 89 ff ff ff ff 19 00 00 00 1f 88 23 00 ..............#. backtrace (crc 838fb36): __kmalloc_cache_noprof+0x284/0x320 padata_alloc_pd+0x20/0x1e0 padata_alloc_shell+0x3b/0xa0 0xffffffffc040a54d cryptomgr_probe+0x43/0xc0 kthread+0xf6/0x1f0 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30
In the Linux kernel, the following vulnerability has been resolved: genirq/msi: Store the IOMMU IOVA directly in msi_desc instead of iommu_cookie The IOMMU translation for MSI message addresses has been a 2-step process, separated in time: 1) iommu_dma_prepare_msi(): A cookie pointer containing the IOVA address is stored in the MSI descriptor when an MSI interrupt is allocated. 2) iommu_dma_compose_msi_msg(): this cookie pointer is used to compute a translated message address. This has an inherent lifetime problem for the pointer stored in the cookie that must remain valid between the two steps. However, there is no locking at the irq layer that helps protect the lifetime. Today, this works under the assumption that the iommu domain is not changed while MSI interrupts being programmed. This is true for normal DMA API users within the kernel, as the iommu domain is attached before the driver is probed and cannot be changed while a driver is attached. Classic VFIO type1 also prevented changing the iommu domain while VFIO was running as it does not support changing the "container" after starting up. However, iommufd has improved this so that the iommu domain can be changed during VFIO operation. This potentially allows userspace to directly race VFIO_DEVICE_ATTACH_IOMMUFD_PT (which calls iommu_attach_group()) and VFIO_DEVICE_SET_IRQS (which calls into iommu_dma_compose_msi_msg()). This potentially causes both the cookie pointer and the unlocked call to iommu_get_domain_for_dev() on the MSI translation path to become UAFs. Fix the MSI cookie UAF by removing the cookie pointer. The translated IOVA address is already known during iommu_dma_prepare_msi() and cannot change. Thus, it can simply be stored as an integer in the MSI descriptor. The other UAF related to iommu_get_domain_for_dev() will be addressed in patch "iommu: Make iommu_dma_prepare_msi() into a generic operation" by using the IOMMU group mutex.
In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtk-star-emac: fix spinlock recursion issues on rx/tx poll Use spin_lock_irqsave and spin_unlock_irqrestore instead of spin_lock and spin_unlock in mtk_star_emac driver to avoid spinlock recursion occurrence that can happen when enabling the DMA interrupts again in rx/tx poll. ``` BUG: spinlock recursion on CPU#0, swapper/0/0 lock: 0xffff00000db9cf20, .magic: dead4ead, .owner: swapper/0/0, .owner_cpu: 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.15.0-rc2-next-20250417-00001-gf6a27738686c-dirty #28 PREEMPT Hardware name: MediaTek MT8365 Open Platform EVK (DT) Call trace: show_stack+0x18/0x24 (C) dump_stack_lvl+0x60/0x80 dump_stack+0x18/0x24 spin_dump+0x78/0x88 do_raw_spin_lock+0x11c/0x120 _raw_spin_lock+0x20/0x2c mtk_star_handle_irq+0xc0/0x22c [mtk_star_emac] __handle_irq_event_percpu+0x48/0x140 handle_irq_event+0x4c/0xb0 handle_fasteoi_irq+0xa0/0x1bc handle_irq_desc+0x34/0x58 generic_handle_domain_irq+0x1c/0x28 gic_handle_irq+0x4c/0x120 do_interrupt_handler+0x50/0x84 el1_interrupt+0x34/0x68 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x6c/0x70 regmap_mmio_read32le+0xc/0x20 (P) _regmap_bus_reg_read+0x6c/0xac _regmap_read+0x60/0xdc regmap_read+0x4c/0x80 mtk_star_rx_poll+0x2f4/0x39c [mtk_star_emac] __napi_poll+0x38/0x188 net_rx_action+0x164/0x2c0 handle_softirqs+0x100/0x244 __do_softirq+0x14/0x20 ____do_softirq+0x10/0x20 call_on_irq_stack+0x24/0x64 do_softirq_own_stack+0x1c/0x40 __irq_exit_rcu+0xd4/0x10c irq_exit_rcu+0x10/0x1c el1_interrupt+0x38/0x68 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x6c/0x70 cpuidle_enter_state+0xac/0x320 (P) cpuidle_enter+0x38/0x50 do_idle+0x1e4/0x260 cpu_startup_entry+0x34/0x3c rest_init+0xdc/0xe0 console_on_rootfs+0x0/0x6c __primary_switched+0x88/0x90 ```
In the Linux kernel, the following vulnerability has been resolved: vxlan: Annotate FDB data races The 'used' and 'updated' fields in the FDB entry structure can be accessed concurrently by multiple threads, leading to reports such as [1]. Can be reproduced using [2]. Suppress these reports by annotating these accesses using READ_ONCE() / WRITE_ONCE(). [1] BUG: KCSAN: data-race in vxlan_xmit / vxlan_xmit write to 0xffff942604d263a8 of 8 bytes by task 286 on cpu 0: vxlan_xmit+0xb29/0x2380 dev_hard_start_xmit+0x84/0x2f0 __dev_queue_xmit+0x45a/0x1650 packet_xmit+0x100/0x150 packet_sendmsg+0x2114/0x2ac0 __sys_sendto+0x318/0x330 __x64_sys_sendto+0x76/0x90 x64_sys_call+0x14e8/0x1c00 do_syscall_64+0x9e/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff942604d263a8 of 8 bytes by task 287 on cpu 2: vxlan_xmit+0xadf/0x2380 dev_hard_start_xmit+0x84/0x2f0 __dev_queue_xmit+0x45a/0x1650 packet_xmit+0x100/0x150 packet_sendmsg+0x2114/0x2ac0 __sys_sendto+0x318/0x330 __x64_sys_sendto+0x76/0x90 x64_sys_call+0x14e8/0x1c00 do_syscall_64+0x9e/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000fffbac6e -> 0x00000000fffbac6f Reported by Kernel Concurrency Sanitizer on: CPU: 2 UID: 0 PID: 287 Comm: mausezahn Not tainted 6.13.0-rc7-01544-gb4b270f11a02 #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 [2] #!/bin/bash set +H echo whitelist > /sys/kernel/debug/kcsan echo !vxlan_xmit > /sys/kernel/debug/kcsan ip link add name vx0 up type vxlan id 10010 dstport 4789 local 192.0.2.1 bridge fdb add 00:11:22:33:44:55 dev vx0 self static dst 198.51.100.1 taskset -c 0 mausezahn vx0 -a own -b 00:11:22:33:44:55 -c 0 -q & taskset -c 2 mausezahn vx0 -a own -b 00:11:22:33:44:55 -c 0 -q &
In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: Fix WARN_ON in nouveau_fence_context_kill() Nouveau is mostly designed in a way that it's expected that fences only ever get signaled through nouveau_fence_signal(). However, in at least one other place, nouveau_fence_done(), can signal fences, too. If that happens (race) a signaled fence remains in the pending list for a while, until it gets removed by nouveau_fence_update(). Should nouveau_fence_context_kill() run in the meantime, this would be a bug because the function would attempt to set an error code on an already signaled fence. Have nouveau_fence_context_kill() check for a fence being signaled.
In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: fix a potential crash on gso_skb handling SFQ has an assumption of always being able to queue at least one packet. However, after the blamed commit, sch->q.len can be inflated by packets in sch->gso_skb, and an enqueue() on an empty SFQ qdisc can be followed by an immediate drop. Fix sfq_drop() to properly clear q->tail in this situation. ip netns add lb ip link add dev to-lb type veth peer name in-lb netns lb ethtool -K to-lb tso off # force qdisc to requeue gso_skb ip netns exec lb ethtool -K in-lb gro on # enable NAPI ip link set dev to-lb up ip -netns lb link set dev in-lb up ip addr add dev to-lb 192.168.20.1/24 ip -netns lb addr add dev in-lb 192.168.20.2/24 tc qdisc replace dev to-lb root sfq limit 100 ip netns exec lb netserver netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 &
In the Linux kernel, the following vulnerability has been resolved: wifi: plfxlc: Remove erroneous assert in plfxlc_mac_release plfxlc_mac_release() asserts that mac->lock is held. This assertion is incorrect, because even if it was possible, it would not be the valid behaviour. The function is used when probe fails or after the device is disconnected. In both cases mac->lock can not be held as the driver is not working with the device at the moment. All functions that use mac->lock unlock it just after it was held. There is also no need to hold mac->lock for plfxlc_mac_release() itself, as mac data is not affected, except for mac->flags, which is modified atomically. This bug leads to the following warning: ================================================================ WARNING: CPU: 0 PID: 127 at drivers/net/wireless/purelifi/plfxlc/mac.c:106 plfxlc_mac_release+0x7d/0xa0 Modules linked in: CPU: 0 PID: 127 Comm: kworker/0:2 Not tainted 6.1.124-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: usb_hub_wq hub_event RIP: 0010:plfxlc_mac_release+0x7d/0xa0 drivers/net/wireless/purelifi/plfxlc/mac.c:106 Call Trace: <TASK> probe+0x941/0xbd0 drivers/net/wireless/purelifi/plfxlc/usb.c:694 usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396 really_probe+0x2ab/0xcb0 drivers/base/dd.c:639 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:785 driver_probe_device+0x50/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2cf/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429 __device_attach+0x359/0x570 drivers/base/dd.c:1015 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489 device_add+0xb48/0xfd0 drivers/base/core.c:3696 usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2165 usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238 usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293 really_probe+0x2ab/0xcb0 drivers/base/dd.c:639 __driver_probe_device+0x1a2/0x3d0 drivers/base/dd.c:785 driver_probe_device+0x50/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2cf/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x183/0x200 drivers/base/bus.c:429 __device_attach+0x359/0x570 drivers/base/dd.c:1015 bus_probe_device+0xba/0x1e0 drivers/base/bus.c:489 device_add+0xb48/0xfd0 drivers/base/core.c:3696 usb_new_device+0xbdd/0x18f0 drivers/usb/core/hub.c:2620 hub_port_connect drivers/usb/core/hub.c:5477 [inline] hub_port_connect_change drivers/usb/core/hub.c:5617 [inline] port_event drivers/usb/core/hub.c:5773 [inline] hub_event+0x2efe/0x5730 drivers/usb/core/hub.c:5855 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> ================================================================ Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: Prevent division by zero The user can set any speed value. If speed is greater than UINT_MAX/8, division by zero is possible. Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: Prevent division by zero The user can set any speed value. If speed is greater than UINT_MAX/8, division by zero is possible. Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: Prevent division by zero The user can set any speed value. If speed is greater than UINT_MAX/8, division by zero is possible. Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: ipvs: fix uninit-value for saddr in do_output_route4 syzbot reports for uninit-value for the saddr argument [1]. commit 4754957f04f5 ("ipvs: do not use random local source address for tunnels") already implies that the input value of saddr should be ignored but the code is still reading it which can prevent to connect the route. Fix it by changing the argument to ret_saddr. [1] BUG: KMSAN: uninit-value in do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 do_output_route4+0x42c/0x4d0 net/netfilter/ipvs/ip_vs_xmit.c:147 __ip_vs_get_out_rt+0x403/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:330 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118 ip_local_out net/ipv4/ip_output.c:127 [inline] ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x267/0x380 net/socket.c:727 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Uninit was created at: slab_post_alloc_hook mm/slub.c:4167 [inline] slab_alloc_node mm/slub.c:4210 [inline] __kmalloc_cache_noprof+0x8fa/0xe00 mm/slub.c:4367 kmalloc_noprof include/linux/slab.h:905 [inline] ip_vs_dest_dst_alloc net/netfilter/ipvs/ip_vs_xmit.c:61 [inline] __ip_vs_get_out_rt+0x35d/0x21d0 net/netfilter/ipvs/ip_vs_xmit.c:323 ip_vs_tunnel_xmit+0x205/0x2380 net/netfilter/ipvs/ip_vs_xmit.c:1136 ip_vs_in_hook+0x1aa5/0x35b0 net/netfilter/ipvs/ip_vs_core.c:2063 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xf7/0x400 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip_local_out+0x758/0x7e0 net/ipv4/ip_output.c:118 ip_local_out net/ipv4/ip_output.c:127 [inline] ip_send_skb+0x6a/0x3c0 net/ipv4/ip_output.c:1501 udp_send_skb+0xfda/0x1b70 net/ipv4/udp.c:1195 udp_sendmsg+0x2fe3/0x33c0 net/ipv4/udp.c:1483 inet_sendmsg+0x1fc/0x280 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x267/0x380 net/socket.c:727 ____sys_sendmsg+0x91b/0xda0 net/socket.c:2566 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2620 __sys_sendmmsg+0x41d/0x880 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xc8/0x140 net/compat.c:364 ia32_sys_call+0x3ffa/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:346 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369 entry_SYSENTER_compat_after_hwframe+0x84/0x8e CPU: 0 UID: 0 PID: 22408 Comm: syz.4.5165 Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(undef) Hardware name: Google Google Compute Engi ---truncated---
In the Linux kernel, the following vulnerability has been resolved: hisi_acc_vfio_pci: fix XQE dma address error The dma addresses of EQE and AEQE are wrong after migration and results in guest kernel-mode encryption services failure. Comparing the definition of hardware registers, we found that there was an error when the data read from the register was combined into an address. Therefore, the address combination sequence needs to be corrected. Even after fixing the above problem, we still have an issue where the Guest from an old kernel can get migrated to new kernel and may result in wrong data. In order to ensure that the address is correct after migration, if an old magic number is detected, the dma address needs to be updated.
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: make sure that ptp_rate is not 0 before configuring timestamping The stmmac platform drivers that do not open-code the clk_ptp_rate value after having retrieved the default one from the device-tree can end up with 0 in clk_ptp_rate (as clk_get_rate can return 0). It will eventually propagate up to PTP initialization when bringing up the interface, leading to a divide by 0: Division by zero in kernel. CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.30-00001-g48313bd5768a #22 Hardware name: STM32 (Device Tree Support) Call trace: unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x6c/0x8c dump_stack_lvl from Ldiv0_64+0x8/0x18 Ldiv0_64 from stmmac_init_tstamp_counter+0x190/0x1a4 stmmac_init_tstamp_counter from stmmac_hw_setup+0xc1c/0x111c stmmac_hw_setup from __stmmac_open+0x18c/0x434 __stmmac_open from stmmac_open+0x3c/0xbc stmmac_open from __dev_open+0xf4/0x1ac __dev_open from __dev_change_flags+0x1cc/0x224 __dev_change_flags from dev_change_flags+0x24/0x60 dev_change_flags from ip_auto_config+0x2e8/0x11a0 ip_auto_config from do_one_initcall+0x84/0x33c do_one_initcall from kernel_init_freeable+0x1b8/0x214 kernel_init_freeable from kernel_init+0x24/0x140 kernel_init from ret_from_fork+0x14/0x28 Exception stack(0xe0815fb0 to 0xe0815ff8) Prevent this division by 0 by adding an explicit check and error log about the actual issue. While at it, remove the same check from stmmac_ptp_register, which then becomes duplicate
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix the warning from __kernel_write_iter [ 2110.972290] ------------[ cut here ]------------ [ 2110.972301] WARNING: CPU: 3 PID: 735 at fs/read_write.c:599 __kernel_write_iter+0x21b/0x280 This patch doesn't allow writing to directory.
In the Linux kernel, the following vulnerability has been resolved: iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_fifo Prevent st_lsm6dsx_read_fifo from falling in an infinite loop in case pattern_len is equal to zero and the device FIFO is not empty.
In the Linux kernel, the following vulnerability has been resolved: net: ch9200: fix uninitialised access during mii_nway_restart In mii_nway_restart() the code attempts to call mii->mdio_read which is ch9200_mdio_read(). ch9200_mdio_read() utilises a local buffer called "buff", which is initialised with control_read(). However "buff" is conditionally initialised inside control_read(): if (err == size) { memcpy(data, buf, size); } If the condition of "err == size" is not met, then "buff" remains uninitialised. Once this happens the uninitialised "buff" is accessed and returned during ch9200_mdio_read(): return (buff[0] | buff[1] << 8); The problem stems from the fact that ch9200_mdio_read() ignores the return value of control_read(), leading to uinit-access of "buff". To fix this we should check the return value of control_read() and return early on error.
In the Linux kernel, the following vulnerability has been resolved: net: pktgen: fix access outside of user given buffer in pktgen_thread_write() Honour the user given buffer size for the strn_len() calls (otherwise strn_len() will access memory outside of the user given buffer).
In the Linux kernel, the following vulnerability has been resolved: virtiofs: add filesystem context source name check In certain scenarios, for example, during fuzz testing, the source name may be NULL, which could lead to a kernel panic. Therefore, an extra check for the source name should be added.
In the Linux kernel, the following vulnerability has been resolved: wifi: brcm80211: fmac: Add error handling for brcmf_usb_dl_writeimage() The function brcmf_usb_dl_writeimage() calls the function brcmf_usb_dl_cmd() but dose not check its return value. The 'state.state' and the 'state.bytes' are uninitialized if the function brcmf_usb_dl_cmd() fails. It is dangerous to use uninitialized variables in the conditions. Add error handling for brcmf_usb_dl_cmd() to jump to error handling path if the brcmf_usb_dl_cmd() fails and the 'state.state' and the 'state.bytes' are uninitialized. Improve the error message to report more detailed error information.
In the Linux kernel, the following vulnerability has been resolved: espintcp: remove encap socket caching to avoid reference leak The current scheme for caching the encap socket can lead to reference leaks when we try to delete the netns. The reference chain is: xfrm_state -> enacp_sk -> netns Since the encap socket is a userspace socket, it holds a reference on the netns. If we delete the espintcp state (through flush or individual delete) before removing the netns, the reference on the socket is dropped and the netns is correctly deleted. Otherwise, the netns may not be reachable anymore (if all processes within the ns have terminated), so we cannot delete the xfrm state to drop its reference on the socket. This patch results in a small (~2% in my tests) performance regression. A GC-type mechanism could be added for the socket cache, to clear references if the state hasn't been used "recently", but it's a lot more complex than just not caching the socket.
In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: prime: fix ttm_bo_delayed_delete oops Fix an oops in ttm_bo_delayed_delete which results from dererencing a dangling pointer: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b7b: 0000 [#1] PREEMPT SMP CPU: 4 UID: 0 PID: 1082 Comm: kworker/u65:2 Not tainted 6.14.0-rc4-00267-g505460b44513-dirty #216 Hardware name: LENOVO 82N6/LNVNB161216, BIOS GKCN65WW 01/16/2024 Workqueue: ttm ttm_bo_delayed_delete [ttm] RIP: 0010:dma_resv_iter_first_unlocked+0x55/0x290 Code: 31 f6 48 c7 c7 00 2b fa aa e8 97 bd 52 ff e8 a2 c1 53 00 5a 85 c0 74 48 e9 88 01 00 00 4c 89 63 20 4d 85 e4 0f 84 30 01 00 00 <41> 8b 44 24 10 c6 43 2c 01 48 89 df 89 43 28 e8 97 fd ff ff 4c 8b RSP: 0018:ffffbf9383473d60 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffffbf9383473d88 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffbf9383473d78 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 6b6b6b6b6b6b6b6b R13: ffffa003bbf78580 R14: ffffa003a6728040 R15: 00000000000383cc FS: 0000000000000000(0000) GS:ffffa00991c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000758348024dd0 CR3: 000000012c259000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: <TASK> ? __die_body.cold+0x19/0x26 ? die_addr+0x3d/0x70 ? exc_general_protection+0x159/0x460 ? asm_exc_general_protection+0x27/0x30 ? dma_resv_iter_first_unlocked+0x55/0x290 dma_resv_wait_timeout+0x56/0x100 ttm_bo_delayed_delete+0x69/0xb0 [ttm] process_one_work+0x217/0x5c0 worker_thread+0x1c8/0x3d0 ? apply_wqattrs_cleanup.part.0+0xc0/0xc0 kthread+0x10b/0x240 ? kthreads_online_cpu+0x140/0x140 ret_from_fork+0x40/0x70 ? kthreads_online_cpu+0x140/0x140 ret_from_fork_asm+0x11/0x20 </TASK> The cause of this is: - drm_prime_gem_destroy calls dma_buf_put(dma_buf) which releases the reference to the shared dma_buf. The reference count is 0, so the dma_buf is destroyed, which in turn decrements the corresponding amdgpu_bo reference count to 0, and the amdgpu_bo is destroyed - calling drm_gem_object_release then dma_resv_fini (which destroys the reservation object), then finally freeing the amdgpu_bo. - nouveau_bo obj->bo.base.resv is now a dangling pointer to the memory formerly allocated to the amdgpu_bo. - nouveau_gem_object_del calls ttm_bo_put(&nvbo->bo) which calls ttm_bo_release, which schedules ttm_bo_delayed_delete. - ttm_bo_delayed_delete runs and dereferences the dangling resv pointer, resulting in a general protection fault. Fix this by moving the drm_prime_gem_destroy call from nouveau_gem_object_del to nouveau_bo_del_ttm. This ensures that it will be run after ttm_bo_delayed_delete.
In the Linux kernel, the following vulnerability has been resolved: firmware: arm_ffa: Set dma_mask for ffa devices Set dma_mask for FFA devices, otherwise DMA allocation using the device pointer lead to following warning: WARNING: CPU: 1 PID: 1 at kernel/dma/mapping.c:597 dma_alloc_attrs+0xe0/0x124
In the Linux kernel, the following vulnerability has been resolved: net: mctp: Set SOCK_RCU_FREE Bind lookup runs under RCU, so ensure that a socket doesn't go away in the middle of a lookup.
In the Linux kernel, the following vulnerability has been resolved: scsi: st: Fix array overflow in st_setup() Change the array size to follow parms size instead of a fixed value.
In the Linux kernel, the following vulnerability has been resolved: igc: fix PTM cycle trigger logic Writing to clear the PTM status 'valid' bit while the PTM cycle is triggered results in unreliable PTM operation. To fix this, clear the PTM 'trigger' and status after each PTM transaction. The issue can be reproduced with the following: $ sudo phc2sys -R 1000 -O 0 -i tsn0 -m Note: 1000 Hz (-R 1000) is unrealistically large, but provides a way to quickly reproduce the issue. PHC2SYS exits with: "ioctl PTP_OFFSET_PRECISE: Connection timed out" when the PTM transaction fails This patch also fixes a hang in igc_probe() when loading the igc driver in the kdump kernel on systems supporting PTM. The igc driver running in the base kernel enables PTM trigger in igc_probe(). Therefore the driver is always in PTM trigger mode, except in brief periods when manually triggering a PTM cycle. When a crash occurs, the NIC is reset while PTM trigger is enabled. Due to a hardware problem, the NIC is subsequently in a bad busmaster state and doesn't handle register reads/writes. When running igc_probe() in the kdump kernel, the first register access to a NIC register hangs driver probing and ultimately breaks kdump. With this patch, igc has PTM trigger disabled most of the time, and the trigger is only enabled for very brief (10 - 100 us) periods when manually triggering a PTM cycle. Chances that a crash occurs during a PTM trigger are not 0, but extremely reduced.
In the Linux kernel, the following vulnerability has been resolved: pwm: mediatek: Prevent divide-by-zero in pwm_mediatek_config() With CONFIG_COMPILE_TEST && !CONFIG_HAVE_CLK, pwm_mediatek_config() has a divide-by-zero in the following line: do_div(resolution, clk_get_rate(pc->clk_pwms[pwm->hwpwm])); due to the fact that the !CONFIG_HAVE_CLK version of clk_get_rate() returns zero. This is presumably just a theoretical problem: COMPILE_TEST overrides the dependency on RALINK which would select COMMON_CLK. Regardless it's a good idea to check for the error explicitly to avoid divide-by-zero. Fixes the following warning: drivers/pwm/pwm-mediatek.o: warning: objtool: .text: unexpected end of section [ukleinek: s/CONFIG_CLK/CONFIG_HAVE_CLK/]
In the Linux kernel, the following vulnerability has been resolved: bpf: Scrub packet on bpf_redirect_peer When bpf_redirect_peer is used to redirect packets to a device in another network namespace, the skb isn't scrubbed. That can lead skb information from one namespace to be "misused" in another namespace. As one example, this is causing Cilium to drop traffic when using bpf_redirect_peer to redirect packets that just went through IPsec decryption to a container namespace. The following pwru trace shows (1) the packet path from the host's XFRM layer to the container's XFRM layer where it's dropped and (2) the number of active skb extensions at each function. NETNS MARK IFACE TUPLE FUNC 4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm_rcv_cb .active_extensions = (__u8)2, 4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm4_rcv_cb .active_extensions = (__u8)2, 4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 gro_cells_receive .active_extensions = (__u8)2, [...] 4026533547 0 eth0 10.244.3.124:35473->10.244.2.158:53 skb_do_redirect .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv_core .active_extensions = (__u8)2, [...] 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 udp_queue_rcv_one_skb .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_policy_check .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_decode_session .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 security_xfrm_decode_session .active_extensions = (__u8)2, 4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 kfree_skb_reason(SKB_DROP_REASON_XFRM_POLICY) .active_extensions = (__u8)2, In this case, there are no XFRM policies in the container's network namespace so the drop is unexpected. When we decrypt the IPsec packet, the XFRM state used for decryption is set in the skb extensions. This information is preserved across the netns switch. When we reach the XFRM policy check in the container's netns, __xfrm_policy_check drops the packet with LINUX_MIB_XFRMINNOPOLS because a (container-side) XFRM policy can't be found that matches the (host-side) XFRM state used for decryption. This patch fixes this by scrubbing the packet when using bpf_redirect_peer, as is done on typical netns switches via veth devices except skb->mark and skb->tstamp are not zeroed.
In the Linux kernel, the following vulnerability has been resolved: objtool, media: dib8000: Prevent divide-by-zero in dib8000_set_dds() If dib8000_set_dds()'s call to dib8000_read32() returns zero, the result is a divide-by-zero. Prevent that from happening. Fixes the following warning with an UBSAN kernel: drivers/media/dvb-frontends/dib8000.o: warning: objtool: dib8000_tune() falls through to next function dib8096p_cfg_DibRx()
In the Linux kernel, the following vulnerability has been resolved: jfs: Prevent copying of nlink with value 0 from disk inode syzbot report a deadlock in diFree. [1] When calling "ioctl$LOOP_SET_STATUS64", the offset value passed in is 4, which does not match the mounted loop device, causing the mapping of the mounted loop device to be invalidated. When creating the directory and creating the inode of iag in diReadSpecial(), read the page of fixed disk inode (AIT) in raw mode in read_metapage(), the metapage data it returns is corrupted, which causes the nlink value of 0 to be assigned to the iag inode when executing copy_from_dinode(), which ultimately causes a deadlock when entering diFree(). To avoid this, first check the nlink value of dinode before setting iag inode. [1] WARNING: possible recursive locking detected 6.12.0-rc7-syzkaller-00212-g4a5df3796467 #0 Not tainted -------------------------------------------- syz-executor301/5309 is trying to acquire lock: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diFree+0x37c/0x2fb0 fs/jfs/jfs_imap.c:889 but task is already holding lock: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b6/0x1630 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(imap->im_aglock[index])); lock(&(imap->im_aglock[index])); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz-executor301/5309: #0: ffff8880422a4420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88804755b390 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline] #1: ffff88804755b390 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x260/0x540 fs/namei.c:4026 #2: ffff888044548920 (&(imap->im_aglock[index])){+.+.}-{3:3}, at: diAlloc+0x1b6/0x1630 #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2460 [inline] #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline] #3: ffff888044548890 (&imap->im_freelock){+.+.}-{3:3}, at: diAllocAG+0x4b7/0x1e50 fs/jfs/jfs_imap.c:1669 #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diNewIAG fs/jfs/jfs_imap.c:2477 [inline] #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocExt fs/jfs/jfs_imap.c:1905 [inline] #4: ffff88804755a618 (&jfs_ip->rdwrlock/1){++++}-{3:3}, at: diAllocAG+0x869/0x1e50 fs/jfs/jfs_imap.c:1669 stack backtrace: CPU: 0 UID: 0 PID: 5309 Comm: syz-executor301 Not tainted 6.12.0-rc7-syzkaller-00212-g4a5df3796467 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 diFree+0x37c/0x2fb0 fs/jfs/jfs_imap.c:889 jfs_evict_inode+0x32d/0x440 fs/jfs/inode.c:156 evict+0x4e8/0x9b0 fs/inode.c:725 diFreeSpecial fs/jfs/jfs_imap.c:552 [inline] duplicateIXtree+0x3c6/0x550 fs/jfs/jfs_imap.c:3022 diNewIAG fs/jfs/jfs_imap.c:2597 [inline] diAllocExt fs/jfs/jfs_imap.c:1905 [inline] diAllocAG+0x17dc/0x1e50 fs/jfs/jfs_imap.c:1669 diAlloc+0x1d2/0x1630 fs/jfs/jfs_imap.c:1590 ialloc+0x8f/0x900 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x1c5/0xba0 fs/jfs/namei.c:225 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4257 do_mkdirat+0x264/0x3a0 fs/namei.c:4280 __do_sys_mkdirat fs/namei.c:4295 [inline] __se_sys_mkdirat fs/namei.c:4293 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4293 do_syscall_x64 arch/x86/en ---truncated---
In the Linux kernel, the following vulnerability has been resolved: sch_htb: make htb_qlen_notify() idempotent htb_qlen_notify() always deactivates the HTB class and in fact could trigger a warning if it is already deactivated. Therefore, it is not idempotent and not friendly to its callers, like fq_codel_dequeue(). Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers' life.
In the Linux kernel, the following vulnerability has been resolved: dm: fix unconditional IO throttle caused by REQ_PREFLUSH When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush() generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC, which causes the flush_bio to be throttled by wbt_wait(). An example from v5.4, similar problem also exists in upstream: crash> bt 2091206 PID: 2091206 TASK: ffff2050df92a300 CPU: 109 COMMAND: "kworker/u260:0" #0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8 #1 [ffff800084a2f820] __schedule at ffff800040bfa0c4 #2 [ffff800084a2f880] schedule at ffff800040bfa4b4 #3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4 #4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc #5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0 #6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254 #7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38 #8 [ffff800084a2fa60] generic_make_request at ffff800040570138 #9 [ffff800084a2fae0] submit_bio at ffff8000405703b4 #10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs] #11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs] #12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs] #13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs] #14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs] #15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs] #16 [ffff800084a2fdb0] process_one_work at ffff800040111d08 #17 [ffff800084a2fe00] worker_thread at ffff8000401121cc #18 [ffff800084a2fe70] kthread at ffff800040118de4 After commit 2def2845cc33 ("xfs: don't allow log IO to be throttled"), the metadata submitted by xlog_write_iclog() should not be throttled. But due to the existence of the dm layer, throttling flush_bio indirectly causes the metadata bio to be throttled. Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes wbt_should_throttle() return false to avoid wbt_wait().
In the Linux kernel, the following vulnerability has been resolved: crypto: null - Use spin lock instead of mutex As the null algorithm may be freed in softirq context through af_alg, use spin locks instead of mutexes to protect the default null algorithm.
In the Linux kernel, the following vulnerability has been resolved: jfs: Fix uninit-value access of imap allocated in the diMount() function syzbot reports that hex_dump_to_buffer is using uninit-value: ===================================================== BUG: KMSAN: uninit-value in hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171 hex_dump_to_buffer+0x888/0x1100 lib/hexdump.c:171 print_hex_dump+0x13d/0x3e0 lib/hexdump.c:276 diFree+0x5ba/0x4350 fs/jfs/jfs_imap.c:876 jfs_evict_inode+0x510/0x550 fs/jfs/inode.c:156 evict+0x723/0xd10 fs/inode.c:796 iput_final fs/inode.c:1946 [inline] iput+0x97b/0xdb0 fs/inode.c:1972 txUpdateMap+0xf3e/0x1150 fs/jfs/jfs_txnmgr.c:2367 txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline] jfs_lazycommit+0x627/0x11d0 fs/jfs/jfs_txnmgr.c:2733 kthread+0x6b9/0xef0 kernel/kthread.c:464 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Uninit was created at: slab_post_alloc_hook mm/slub.c:4121 [inline] slab_alloc_node mm/slub.c:4164 [inline] __kmalloc_cache_noprof+0x8e3/0xdf0 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] diMount+0x61/0x7f0 fs/jfs/jfs_imap.c:105 jfs_mount+0xa8e/0x11d0 fs/jfs/jfs_mount.c:176 jfs_fill_super+0xa47/0x17c0 fs/jfs/super.c:523 get_tree_bdev_flags+0x6ec/0x910 fs/super.c:1636 get_tree_bdev+0x37/0x50 fs/super.c:1659 jfs_get_tree+0x34/0x40 fs/jfs/super.c:635 vfs_get_tree+0xb1/0x5a0 fs/super.c:1814 do_new_mount+0x71f/0x15e0 fs/namespace.c:3560 path_mount+0x742/0x1f10 fs/namespace.c:3887 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount+0x71f/0x800 fs/namespace.c:4088 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4088 x64_sys_call+0x39bf/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f ===================================================== The reason is that imap is not properly initialized after memory allocation. It will cause the snprintf() function to write uninitialized data into linebuf within hex_dump_to_buffer(). Fix this by using kzalloc instead of kmalloc to clear its content at the beginning in diMount().
In the Linux kernel, the following vulnerability has been resolved: btrfs: adjust subpage bit start based on sectorsize When running machines with 64k page size and a 16k nodesize we started seeing tree log corruption in production. This turned out to be because we were not writing out dirty blocks sometimes, so this in fact affects all metadata writes. When writing out a subpage EB we scan the subpage bitmap for a dirty range. If the range isn't dirty we do bit_start++; to move onto the next bit. The problem is the bitmap is based on the number of sectors that an EB has. So in this case, we have a 64k pagesize, 16k nodesize, but a 4k sectorsize. This means our bitmap is 4 bits for every node. With a 64k page size we end up with 4 nodes per page. To make this easier this is how everything looks [0 16k 32k 48k ] logical address [0 4 8 12 ] radix tree offset [ 64k page ] folio [ 16k eb ][ 16k eb ][ 16k eb ][ 16k eb ] extent buffers [ | | | | | | | | | | | | | | | | ] bitmap Now we use all of our addressing based on fs_info->sectorsize_bits, so as you can see the above our 16k eb->start turns into radix entry 4. When we find a dirty range for our eb, we correctly do bit_start += sectors_per_node, because if we start at bit 0, the next bit for the next eb is 4, to correspond to eb->start 16k. However if our range is clean, we will do bit_start++, which will now put us offset from our radix tree entries. In our case, assume that the first time we check the bitmap the block is not dirty, we increment bit_start so now it == 1, and then we loop around and check again. This time it is dirty, and we go to find that start using the following equation start = folio_start + bit_start * fs_info->sectorsize; so in the case above, eb->start 0 is now dirty, and we calculate start as 0 + 1 * fs_info->sectorsize = 4096 4096 >> 12 = 1 Now we're looking up the radix tree for 1, and we won't find an eb. What's worse is now we're using bit_start == 1, so we do bit_start += sectors_per_node, which is now 5. If that eb is dirty we will run into the same thing, we will look at an offset that is not populated in the radix tree, and now we're skipping the writeout of dirty extent buffers. The best fix for this is to not use sectorsize_bits to address nodes, but that's a larger change. Since this is a fs corruption problem fix it simply by always using sectors_per_node to increment the start bit.
In the Linux kernel, the following vulnerability has been resolved: x86/mm: Eliminate window where TLB flushes may be inadvertently skipped tl;dr: There is a window in the mm switching code where the new CR3 is set and the CPU should be getting TLB flushes for the new mm. But should_flush_tlb() has a bug and suppresses the flush. Fix it by widening the window where should_flush_tlb() sends an IPI. Long Version: === History === There were a few things leading up to this. First, updating mm_cpumask() was observed to be too expensive, so it was made lazier. But being lazy caused too many unnecessary IPIs to CPUs due to the now-lazy mm_cpumask(). So code was added to cull mm_cpumask() periodically[2]. But that culling was a bit too aggressive and skipped sending TLB flushes to CPUs that need them. So here we are again. === Problem === The too-aggressive code in should_flush_tlb() strikes in this window: // Turn on IPIs for this CPU/mm combination, but only // if should_flush_tlb() agrees: cpumask_set_cpu(cpu, mm_cpumask(next)); next_tlb_gen = atomic64_read(&next->context.tlb_gen); choose_new_asid(next, next_tlb_gen, &new_asid, &need_flush); load_new_mm_cr3(need_flush); // ^ After 'need_flush' is set to false, IPIs *MUST* // be sent to this CPU and not be ignored. this_cpu_write(cpu_tlbstate.loaded_mm, next); // ^ Not until this point does should_flush_tlb() // become true! should_flush_tlb() will suppress TLB flushes between load_new_mm_cr3() and writing to 'loaded_mm', which is a window where they should not be suppressed. Whoops. === Solution === Thankfully, the fuzzy "just about to write CR3" window is already marked with loaded_mm==LOADED_MM_SWITCHING. Simply checking for that state in should_flush_tlb() is sufficient to ensure that the CPU is targeted with an IPI. This will cause more TLB flush IPIs. But the window is relatively small and I do not expect this to cause any kind of measurable performance impact. Update the comment where LOADED_MM_SWITCHING is written since it grew yet another user. Peter Z also raised a concern that should_flush_tlb() might not observe 'loaded_mm' and 'is_lazy' in the same order that switch_mm_irqs_off() writes them. Add a barrier to ensure that they are observed in the order they are written.
A vulnerability was reported in the Open vSwitch sub-component in the Linux Kernel. The flaw occurs when a recursive operation of code push recursively calls into the code block. The OVS module does not validate the stack depth, pushing too many frames and causing a stack overflow. As a result, this can lead to a crash or other related issues.
An issue was discovered in the Linux kernel before 5.15.11. There is a memory leak in the __rds_conn_create() function in net/rds/connection.c in a certain combination of circumstances.
In the Linux kernel, the following vulnerability has been resolved: ceph: fix deadlock or deadcode of misusing dget() The lock order is incorrect between denty and its parent, we should always make sure that the parent get the lock first. But since this deadcode is never used and the parent dir will always be set from the callers, let's just remove it.
In the Linux kernel, the following vulnerability has been resolved: clk: sunxi-ng: h6: Reparent CPUX during PLL CPUX rate change While PLL CPUX clock rate change when CPU is running from it works in vast majority of cases, now and then it causes instability. This leads to system crashes and other undefined behaviour. After a lot of testing (30+ hours) while also doing a lot of frequency switches, we can't observe any instability issues anymore when doing reparenting to stable clock like 24 MHz oscillator.
QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately.
In the Linux kernel, the following vulnerability has been resolved: tty: n_gsm: require CAP_NET_ADMIN to attach N_GSM0710 ldisc Any unprivileged user can attach N_GSM0710 ldisc, but it requires CAP_NET_ADMIN to create a GSM network anyway. Require initial namespace CAP_NET_ADMIN to do that.
In the Linux kernel, the following vulnerability has been resolved: ACPI: video: check for error while searching for backlight device parent If acpi_get_parent() called in acpi_video_dev_register_backlight() fails, for example, because acpi_ut_acquire_mutex() fails inside acpi_get_parent), this can lead to incorrect (uninitialized) acpi_parent handle being passed to acpi_get_pci_dev() for detecting the parent pci device. Check acpi_get_parent() result and set parent device only in case of success. Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: ACPI: LPIT: Avoid u32 multiplication overflow In lpit_update_residency() there is a possibility of overflow in multiplication, if tsc_khz is large enough (> UINT_MAX/1000). Change multiplication to mul_u32_u32(). Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved: net/ipv6: release expired exception dst cached in socket Dst objects get leaked in ip6_negative_advice() when this function is executed for an expired IPv6 route located in the exception table. There are several conditions that must be fulfilled for the leak to occur: * an ICMPv6 packet indicating a change of the MTU for the path is received, resulting in an exception dst being created * a TCP connection that uses the exception dst for routing packets must start timing out so that TCP begins retransmissions * after the exception dst expires, the FIB6 garbage collector must not run before TCP executes ip6_negative_advice() for the expired exception dst When TCP executes ip6_negative_advice() for an exception dst that has expired and if no other socket holds a reference to the exception dst, the refcount of the exception dst is 2, which corresponds to the increment made by dst_init() and the increment made by the TCP socket for which the connection is timing out. The refcount made by the socket is never released. The refcount of the dst is decremented in sk_dst_reset() but that decrement is counteracted by a dst_hold() intentionally placed just before the sk_dst_reset() in ip6_negative_advice(). After ip6_negative_advice() has finished, there is no other object tied to the dst. The socket lost its reference stored in sk_dst_cache and the dst is no longer in the exception table. The exception dst becomes a leaked object. As a result of this dst leak, an unbalanced refcount is reported for the loopback device of a net namespace being destroyed under kernels that do not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"): unregister_netdevice: waiting for lo to become free. Usage count = 2 Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The patch that introduced the dst_hold() in ip6_negative_advice() was 92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22 merely refactored the code with regards to the dst refcount so the issue was present even before 92f1655aa2b22. The bug was introduced in 54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually expired.") where the expired cached route is deleted and the sk_dst_cache member of the socket is set to NULL by calling dst_negative_advice() but the refcount belonging to the socket is left unbalanced. The IPv4 version - ipv4_negative_advice() - is not affected by this bug. When the TCP connection times out ipv4_negative_advice() merely resets the sk_dst_cache of the socket while decrementing the refcount of the exception dst.
In the Linux kernel, the following vulnerability has been resolved: drm/bridge: tpd12s015: Drop buggy __exit annotation for remove function With tpd12s015_remove() marked with __exit this function is discarded when the driver is compiled as a built-in. The result is that when the driver unbinds there is no cleanup done which results in resource leakage or worse.
In the Linux kernel, the following vulnerability has been resolved: io_uring: drop any code related to SCM_RIGHTS This is dead code after we dropped support for passing io_uring fds over SCM_RIGHTS, get rid of it.
In the Linux kernel, the following vulnerability has been resolved: pipe: wakeup wr_wait after setting max_usage Commit c73be61cede5 ("pipe: Add general notification queue support") a regression was introduced that would lock up resized pipes under certain conditions. See the reproducer in [1]. The commit resizing the pipe ring size was moved to a different function, doing that moved the wakeup for pipe->wr_wait before actually raising pipe->max_usage. If a pipe was full before the resize occured it would result in the wakeup never actually triggering pipe_write. Set @max_usage and @nr_accounted before waking writers if this isn't a watch queue. [Christian Brauner <brauner@kernel.org>: rewrite to account for watch queues]