Affected: Linux

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

powerpc/pseries/iommu: IOMMU table is not initialized for kdump over SR-IOV

When kdump kernel tries to copy dump data over SR-IOV, LPAR panics due to NULL pointer exception:

Kernel attempted to read user page (0) - exploit attempt? (uid: 0) BUG: Kernel NULL pointer dereference on read at 0x00000000 Faulting instruction address: 0xc000000020847ad4 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: mlx5_core(+) vmx_crypto pseries_wdt papr_scm libnvdimm mlxfw tls psample sunrpc fuse overlay squashfs loop CPU: 12 PID: 315 Comm: systemd-udevd Not tainted 6.4.0-Test102+ #12 Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NH1060_008) hv:phyp pSeries NIP: c000000020847ad4 LR: c00000002083b2dc CTR: 00000000006cd18c REGS: c000000029162ca0 TRAP: 0300 Not tainted (6.4.0-Test102+) MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 48288244 XER: 00000008 CFAR: c00000002083b2d8 DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 1 ... NIP _find_next_zero_bit+0x24/0x110 LR bitmap_find_next_zero_area_off+0x5c/0xe0 Call Trace: dev_printk_emit+0x38/0x48 (unreliable) iommu_area_alloc+0xc4/0x180 iommu_range_alloc+0x1e8/0x580 iommu_alloc+0x60/0x130 iommu_alloc_coherent+0x158/0x2b0 dma_iommu_alloc_coherent+0x3c/0x50 dma_alloc_attrs+0x170/0x1f0 mlx5_cmd_…