kernel/linux.git/arch, branch v6.6.152

KVM: x86/mmu: WARN and clear role.invalid when creating a child shadow page

2026-08-19T16:13:13+00:00

commit 5ec42d57655c690234c14aece6dd3f209778c1d8 upstream. Explicitly clear role.invalid when deriving a child shadow page's role from its parent to harden against bugs elsewhere in KVM, as violating KVM's invariant that invalid pages are NOT on the list of active MMU pages leads to use-after-free due to __kvm_mmu_prepare_zap_page() using list_add() instead of list_move() when processing an invalid shadow page, i.e. makes a bad situation far worse. Yell loudly if the parent is invalid, as it means KVM has missed a validity check, i.e. KVM is attempting to map memory using an invalid/obsolete root, but continue on as the child is otherwise still a valid shadow page. ================================================================== BUG: KASAN: slab-use-after-free in __kvm_mmu_get_shadow_page+0x1817/0x1860 [kvm] Write of size 8 at addr ff11000153dd1368 by task repro/853 CPU: 1 UID: 1000 PID: 853 Comm: repro Not tainted 7.2.0-rc2-3aec122bdcaf-next-vm #5 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack_lvl+0x4b/0x70 print_report+0x153/0x49c kasan_report+0xbc/0xf0 __kvm_mmu_get_shadow_page+0x1817/0x1860 [kvm] mmu_alloc_root+0x141/0x320 [kvm] kvm_mmu_load+0x612/0x20f0 [kvm] kvm_arch_vcpu_ioctl_run+0x3dd5/0x6150 [kvm] kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm] __x64_sys_ioctl+0x131/0x1b0 do_syscall_64+0x67/0x5f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Allocated by task 853: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x5f/0x70 kmem_cache_alloc_noprof+0xfe/0x2e0 __kvm_mmu_topup_memory_cache+0x135/0x530 [kvm] paging64_page_fault+0x318/0x1e30 [kvm] kvm_mmu_do_page_fault+0x21d/0x630 [kvm] kvm_mmu_page_fault+0x18c/0x17b0 [kvm] kvm_arch_vcpu_ioctl_run+0x1f35/0x6150 [kvm] kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm] __x64_sys_ioctl+0x131/0x1b0 do_syscall_64+0x67/0x5f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 853: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x43/0x70 kmem_cache_free+0xe2/0x400 kvm_mmu_commit_zap_page.part.0+0x1e2/0x310 [kvm] kvm_mmu_free_roots+0x283/0x560 [kvm] kvm_arch_vcpu_ioctl_run+0x33c8/0x6150 [kvm] kvm_vcpu_ioctl+0x5e4/0x10d0 [kvm] __x64_sys_ioctl+0x131/0x1b0 do_syscall_64+0x67/0x5f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Reported-by: Hyunwoo Kim Fixes: a770f6f28b1a ("KVM: MMU: Inherit a shadow page's guest level count from vcpu setup") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: s390: pci: Fix aisb calculation

2026-08-19T16:13:10+00:00

[ Upstream commit 0cfe660559e857d7c00ab86c73e4510ce069086f ] The current implementation of aisb calculation will erroneously index via an unsigned long * as well as multiply by 8B for every 64-bits in the offset; only one or the other is required. This throws off aisb calculations once the number of devices exceeds 64, and can result in out-of-bounds access as well as failure to indicate summary bits associated with those devices in guests. Fix this by converting to a physical address before applying the offset, as is already done in arch/s390/pci/pci_irq.c. Fixes: 3c5a1b6f0a18 ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding") Signed-off-by: Matthew Rosato Reviewed-by: Niklas Schnelle Signed-off-by: Christian Borntraeger [alifm@linux.ibm.com: Resolved merge conflict] Signed-off-by: Farhan Ali Signed-off-by: Sasha Levin

KVM: s390: pci: Fix resource leak on IRQ registration failure

2026-08-19T16:13:10+00:00

[ Upstream commit 5580c9858f1e00f60191eb09c3add359836d60b6 ] Currently if kvm_zpci_set_airq() fails, kvm_s390_pci_aif_enable() returns the error code but doesn't do any resource cleanup thus leaking resources. Fix this by cleaning up all the resources such as the GAITE, AIBV, AISB and unpinning any pinned pages. While at it, remove dead code that stored FIB values that were never referenced. As part of the cleanup, we are also holding the aift_lock a bit longer, as we hold the lock while executing the MPCIFC instruction. Though this is not strictly necessary, it means we don't have to drop and re-acquire in the error case. Fixes: 3c5a1b6f0a18 ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding") Cc: stable@vger.kernel.org Reviewed-by: Matthew Rosato Reviewed-by: Christian Borntraeger Signed-off-by: Farhan Ali Tested-by: Matthew Rosato Signed-off-by: Christian Borntraeger [alifm@linux.ibm.com: Resolved merge conflict] Signed-off-by: Farhan Ali Signed-off-by: Sasha Levin

KVM: s390: pci: Fix missing error codes and memory unaccounting

2026-08-19T16:13:10+00:00

[ Upstream commit f86842e4d6c482300f4567f492d512c9ccf5bc4f ] In kvm_s390_pci_aif_enable() two error paths failed to set an error code, causing the function to return 0 on failure. It also failed to rollback memory accounting on failure. Fix both by propagating an error code on failure and calling unaccount_mem() in the cleanup path. Fixes: 3c5a1b6f0a18 ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding") Cc: stable@vger.kernel.org Reviewed-by: Christian Borntraeger Reviewed-by: Matthew Rosato Signed-off-by: Farhan Ali Tested-by: Matthew Rosato Signed-off-by: Christian Borntraeger [alifm@linux.ibm.com: Resolve merge conflict] Signed-off-by: Farhan Ali Signed-off-by: Sasha Levin

KVM: s390: pci: Fix memory accounting for pinned/unpinned pages

2026-08-19T16:13:10+00:00

[ Upstream commit 36f6999ecde3976731a8bfc0b8e667da6f593069 ] The account_mem() and unaccount_mem() functions call get_uid() which increments the reference count of struct user_struct on every invocation. But we don't decrement the count by calling free_uid(). It also accounted/unaccounted the pages against the current->mm. But its possible the unaccount_mem() can be called from a different process context than the one that originally pinned the pages. Let's fix this by storing the pinning process user_struct and mm_struct when accounting for pinned pages, and subsequently free these resources when the pages are unpinned. Fixes: 3c5a1b6f0a18 ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding") Cc: stable@vger.kernel.org Reviewed-by: Christian Borntraeger Reviewed-by: Matthew Rosato Signed-off-by: Farhan Ali Tested-by: Matthew Rosato [borntraeger@linux.ibm.com: Fixed whitespace] Signed-off-by: Christian Borntraeger [alifm@linux.ibm.com: Resolve merge conflict] Signed-off-by: Farhan Ali Signed-off-by: Sasha Levin

ARM: dts: BCM5301X: fix PCIe controller 2 second interrupt

2026-08-19T16:13:05+00:00

[ Upstream commit bab4d538f8485e0d48538fcb82b285df3779278e ] PCIe controller 2 has interrupts 0-4 mapping to GIC SPI 138-142. The mapping for interrupt 1 was incorrectly set to 138 due to a copy-paste error. Fix it to 139. Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Link: https://lore.kernel.org/r/20260725215722.9323-1-rosenp@gmail.com Fixes: 3b3e35b279be ("ARM: dts: BCM5301X: Relicense AXI interrupts code to the GPL 2.0+ / MIT") Signed-off-by: Florian Fainelli Signed-off-by: Sasha Levin

ARM: npcm: Fix OF node refcount leaks in SMP setup

2026-08-19T16:13:05+00:00

[ Upstream commit 8eb052f48331474c2789d07b7f11165c323bd2f9 ] npcm7xx_smp_boot_secondary() and npcm7xx_smp_prepare_cpus() look up the GCR and SCU nodes with of_find_compatible_node(). The returned nodes are used for of_iomap(), but the node references are never released. of_iomap() does not consume the device node reference, and iounmap() only releases the MMIO mapping. Drop each node reference after the corresponding mapping attempt. Fixes: 7bffa14c9aed ("arm: npcm: add basic support for Nuvoton BMCs") Signed-off-by: Yuho Choi Reviewed-by: Avi Fishman Signed-off-by: Andrew Jeffery Signed-off-by: Sasha Levin

um: vector: fix use-after-free in vector_mmsg_rx()

2026-08-09T18:21:54+00:00

commit af421e9aed3920c7ac88c24daa48606c7112feca upstream. When vector_mmsg_rx() discards a packet whose overlay header fails verify_header(), it frees the skb and continues the loop: if (header_check < 0) { dev_kfree_skb_irq(skb); vp->estats.rx_encaps_errors++; continue; } The normal and short-packet paths fall through to the bottom of the loop body, which clears the consumed slot and advances the cursors: (*skbuff_vector) = NULL; mmsg_vector++; skbuff_vector++; The verify_header() < 0 path skips that via continue, so the freed skb is left in skbuff_vector[] and the cursors do not advance. The next iteration reads the same slot, gets the freed skb, and frees it again, producing a refcount underflow / use-after-free in the RX path. Discard the slot the same way the other paths do before continuing. Only transports whose verify_header() can return negative are affected: GRE and L2TPv3 do so on a cookie/session-id mismatch (raw/tap do not), so any peer on such a transport can trigger it without authentication. Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Michael Bommarito Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman

powerpc/ps3: Fix map failure path in dma_ioc0_map_pages()

2026-08-09T18:21:54+00:00

commit 0bb024f11d120abff3e8db9144a585b9d7fb8459 upstream. If lv1_put_iopte() fails in dma_ioc0_map_pages(), the error path decrements iopage but keeps using the failed mapping's offset. As a result, it repeatedly tries to invalidate the failed IOPTE slot and leaves the already installed IOPTEs valid. Recompute offset and invalidate the installed IOPTEs instead. Fixes: 6bb5cf102541 ("[POWERPC] PS3: System-bus rework") Cc: stable@vger.kernel.org Signed-off-by: Thorsten Blum Reviewed-by: Ritesh Harjani (IBM) Reviewed-by: Geert Uytterhoeven Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260711130931.740719-3-thorsten.blum@linux.dev Signed-off-by: Greg Kroah-Hartman

KVM: s390: pci: Validate AIBV and AISB before pinning guest pages

2026-08-09T18:21:51+00:00

commit 868d32ac72cba21c5c6d8a66a814b7c25a3a5c01 upstream. The AIBV holds one bit per MSI-X vector for a given function. The size of the bit vector is derived from the NOI and the AIBVO. If the size of the AIBV exceeds a single page boundary, then reject the request as we cannot safely pin the guest AIBV. Similarly reject the request if the AISB address is not 8-byte aligned as the architecture requires doubleword alignment for the summary bit address. Since the AISBO can address up to 64 bits, the size of the AISB can only be 8 bytes for the function. This also ensures the AISB doesn't exceed a single page boundary. Fixes: 3c5a1b6f0a18 ("KVM: s390: pci: provide routines for enabling/disabling interrupt forwarding") Cc: stable@vger.kernel.org Reviewed-by: Christian Borntraeger Reviewed-by: Matthew Rosato Signed-off-by: Farhan Ali Tested-by: Matthew Rosato Signed-off-by: Christian Borntraeger Signed-off-by: Greg Kroah-Hartman