Affected: Linux

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

sfc: fix kernel panic when creating VF

When creating VFs a kernel panic can happen when calling to efx_ef10_try_update_nic_stats_vf.

When releasing a DMA coherent buffer, sometimes, I don't know in what specific circumstances, it has to unmap memory with vunmap. It is disallowed to do that in IRQ context or with BH disabled. Otherwise, we hit this line in vunmap, causing the crash: BUG_ON(in_interrupt());

This patch reenables BH to release the buffer.

Log messages when the bug is hit: kernel BUG at mm/vmalloc.c:2727! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 6 PID: 1462 Comm: NetworkManager Kdump: loaded Tainted: G I --------- --- 5.14.0-119.el9.x86_64 #1 Hardware name: Dell Inc. PowerEdge R740/06WXJT, BIOS 2.8.2 08/27/2020 RIP: 0010:vunmap+0x2e/0x30 ...skip... Call Trace: __iommu_dma_free+0x96/0x100 efx_nic_free_buffer+0x2b/0x40 [sfc] efx_ef10_try_update_nic_stats_vf+0x14a/0x1c0 [sfc] efx_ef10_update_stats_vf+0x18/0x40 [sfc] efx_start_all+0x15e/0x1d0 [sfc] efx_net_open+0x5a/0xe0 [sfc] __dev_open+0xe7/0x1a0 __dev_change_flags+0x1d7/0x240 dev_change_flags+0x21/0x60 ...skip...

kernel: off-path attacker may inject data or terminate victim's TCP session kernel: race condition in VT_RESIZEX ioctl when vc_cons[i].d is already NULL leading to NULL pointer dereference kernel: use-after-free vulnerability in function sco_sock_sendmsg() kernel: memory leak for large arguments in video_usercopy function in drivers/media/v4l2-core/v4l2-ioctl.c kernel: mm/damon/dbgfs: protect targets destructions with kdamond_lock kernel: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() kernel: veth: ensure skb entering GRO are not cloned. kernel: inet: fully convert sk->sk_rx_dst to RCU rules kernel: NFSD: Fix READDIR buffer overflow kernel: cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init kernel: nvme-rdma: destroy cm id before destroy qp to avoid use after free kernel: regmap: Fix possible double-free in regcache_rbtree_exit() kernel: ethtool: do not perform operations on net devices being unregistered kernel: scsi: scsi_debug: Fix type in min_t to avoid stack OOB kernel: KVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU kernel: udmabuf: validate ubuf->pagecount kernel: drm/virtio: Ensure that objs is not NULL in virtio_gpu_array_put_free() kernel: smb2_ioctl_query_info NULL pointer dereference kernel: NULL pointer dereference in udf_expand_file_adinicbdue() during writeback kernel: swiotlb information leak with DMA_FROM_DEVICE kernel: uninitialized registers on stack in nft_do_chain can cause kernel pointer leakage to UM k…