The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 37b2a6510a48ca361ced679f92682b7b7d7d0330 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini pbonzini@redhat.com Date: Tue, 8 Mar 2022 04:49:37 -0500 Subject: [PATCH] KVM: use __vcalloc for very large allocations

Allocations whose size is related to the memslot size can be arbitrarily large. Do not use kvzalloc/kvcalloc, as those are limited to "not crazy" sizes that fit in 32 bits.

Cc: stable@vger.kernel.org Fixes: 7661809d493b ("mm: don't allow oversized kvmalloc() calls") Reviewed-by: David Hildenbrand david@redhat.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com

diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index e414ca44839f..be441403925b 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -251,7 +251,7 @@ int kvmppc_uvmem_slot_init(struct kvm *kvm, const struct kvm_memory_slot *slot) p = kzalloc(sizeof(*p), GFP_KERNEL); if (!p) return -ENOMEM; - p->pfns = vzalloc(array_size(slot->npages, sizeof(*p->pfns))); + p->pfns = vcalloc(slot->npages, sizeof(*p->pfns)); if (!p->pfns) { kfree(p); return -ENOMEM; diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c index 68eb1fb548b6..2e09d1b6249f 100644 --- a/arch/x86/kvm/mmu/page_track.c +++ b/arch/x86/kvm/mmu/page_track.c @@ -47,8 +47,8 @@ int kvm_page_track_create_memslot(struct kvm *kvm, continue;

slot->arch.gfn_track[i] = - kvcalloc(npages, sizeof(*slot->arch.gfn_track[i]), - GFP_KERNEL_ACCOUNT); + __vcalloc(npages, sizeof(*slot->arch.gfn_track[i]), + GFP_KERNEL_ACCOUNT); if (!slot->arch.gfn_track[i]) goto track_free; } @@ -75,7 +75,8 @@ int kvm_page_track_write_tracking_alloc(struct kvm_memory_slot *slot) if (slot->arch.gfn_track[KVM_PAGE_TRACK_WRITE]) return 0;

- gfn_track = kvcalloc(slot->npages, sizeof(*gfn_track), GFP_KERNEL_ACCOUNT); + gfn_track = __vcalloc(slot->npages, sizeof(*gfn_track), + GFP_KERNEL_ACCOUNT); if (gfn_track == NULL) return -ENOMEM;

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f79bf4552082..4fa4d8269e5b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11838,7 +11838,7 @@ int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages) if (slot->arch.rmap[i]) continue;

- slot->arch.rmap[i] = kvcalloc(lpages, sz, GFP_KERNEL_ACCOUNT); + slot->arch.rmap[i] = __vcalloc(lpages, sz, GFP_KERNEL_ACCOUNT); if (!slot->arch.rmap[i]) { memslot_rmap_free(slot); return -ENOMEM; @@ -11875,7 +11875,7 @@ static int kvm_alloc_memslot_metadata(struct kvm *kvm,

lpages = __kvm_mmu_slot_lpages(slot, npages, level);

- linfo = kvcalloc(lpages, sizeof(*linfo), GFP_KERNEL_ACCOUNT); + linfo = __vcalloc(lpages, sizeof(*linfo), GFP_KERNEL_ACCOUNT); if (!linfo) goto out_free;

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index c941b97fa133..69c318fdff61 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1274,9 +1274,9 @@ static int kvm_vm_release(struct inode *inode, struct file *filp) */ static int kvm_alloc_dirty_bitmap(struct kvm_memory_slot *memslot) { - unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot); + unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(memslot);

- memslot->dirty_bitmap = kvzalloc(dirty_bytes, GFP_KERNEL_ACCOUNT); + memslot->dirty_bitmap = __vcalloc(2, dirty_bytes, GFP_KERNEL_ACCOUNT); if (!memslot->dirty_bitmap) return -ENOMEM;