On Wed, Dec 04, 2024 at 12:22:59PM -0800, Jing Zhang wrote: > commit 7fe28d7e68f92cc3d0668b8f2fbdf5c303ac3022 upstream. > > In all the vgic_its_save_*() functinos, they do not check whether > the data length is 8 bytes before calling vgic_write_guest_lock. > This patch adds the check. To prevent the kernel from being blown up > when the fault occurs, KVM_BUG_ON() is used. And the other BUG_ON()s > are replaced together. > > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Kunkun Jiang <jiangkunkun@xxxxxxxxxx> > [Jing: Update with the new entry read/write helpers] > Signed-off-by: Jing Zhang <jingzhangos@xxxxxxxxxx> > Link: https://lore.kernel.org/r/20241107214137.428439-4-jingzhangos@xxxxxxxxxx > Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx> For the series: Acked-by: Oliver Upton <oliver.upton@xxxxxxxxx> -- Thanks, Oliver > --- > virt/kvm/arm/vgic/vgic-its.c | 20 ++++++++------------ > virt/kvm/arm/vgic/vgic.h | 24 ++++++++++++++++++++++++ > 2 files changed, 32 insertions(+), 12 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index f4ce08c0d0be..f091d4c9120a 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -2134,7 +2134,6 @@ static int scan_its_table(struct vgic_its *its, gpa_t base, int size, u32 esz, > static int vgic_its_save_ite(struct vgic_its *its, struct its_device *dev, > struct its_ite *ite, gpa_t gpa, int ite_esz) > { > - struct kvm *kvm = its->dev->kvm; > u32 next_offset; > u64 val; > > @@ -2143,7 +2142,8 @@ static int vgic_its_save_ite(struct vgic_its *its, struct its_device *dev, > ((u64)ite->irq->intid << KVM_ITS_ITE_PINTID_SHIFT) | > ite->collection->collection_id; > val = cpu_to_le64(val); > - return kvm_write_guest_lock(kvm, gpa, &val, ite_esz); > + > + return vgic_its_write_entry_lock(its, gpa, val, ite_esz); > } > > /** > @@ -2279,7 +2279,6 @@ static int vgic_its_restore_itt(struct vgic_its *its, struct its_device *dev) > static int vgic_its_save_dte(struct vgic_its *its, struct its_device *dev, > gpa_t ptr, int dte_esz) > { > - struct kvm *kvm = its->dev->kvm; > u64 val, itt_addr_field; > u32 next_offset; > > @@ -2290,7 +2289,8 @@ static int vgic_its_save_dte(struct vgic_its *its, struct its_device *dev, > (itt_addr_field << KVM_ITS_DTE_ITTADDR_SHIFT) | > (dev->num_eventid_bits - 1)); > val = cpu_to_le64(val); > - return kvm_write_guest_lock(kvm, ptr, &val, dte_esz); > + > + return vgic_its_write_entry_lock(its, ptr, val, dte_esz); > } > > /** > @@ -2470,7 +2470,8 @@ static int vgic_its_save_cte(struct vgic_its *its, > ((u64)collection->target_addr << KVM_ITS_CTE_RDBASE_SHIFT) | > collection->collection_id); > val = cpu_to_le64(val); > - return kvm_write_guest_lock(its->dev->kvm, gpa, &val, esz); > + > + return vgic_its_write_entry_lock(its, gpa, val, esz); > } > > static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz) > @@ -2481,8 +2482,7 @@ static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz) > u64 val; > int ret; > > - BUG_ON(esz > sizeof(val)); > - ret = kvm_read_guest_lock(kvm, gpa, &val, esz); > + ret = vgic_its_read_entry_lock(its, gpa, &val, esz); > if (ret) > return ret; > val = le64_to_cpu(val); > @@ -2516,7 +2516,6 @@ static int vgic_its_save_collection_table(struct vgic_its *its) > u64 baser = its->baser_coll_table; > gpa_t gpa = GITS_BASER_ADDR_48_to_52(baser); > struct its_collection *collection; > - u64 val; > size_t max_size, filled = 0; > int ret, cte_esz = abi->cte_esz; > > @@ -2540,10 +2539,7 @@ static int vgic_its_save_collection_table(struct vgic_its *its) > * table is not fully filled, add a last dummy element > * with valid bit unset > */ > - val = 0; > - BUG_ON(cte_esz > sizeof(val)); > - ret = kvm_write_guest_lock(its->dev->kvm, gpa, &val, cte_esz); > - return ret; > + return vgic_its_write_entry_lock(its, gpa, 0, cte_esz); > } > > /** > diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h > index 83066a81b16a..ac553f9171a6 100644 > --- a/virt/kvm/arm/vgic/vgic.h > +++ b/virt/kvm/arm/vgic/vgic.h > @@ -6,6 +6,7 @@ > #define __KVM_ARM_VGIC_NEW_H__ > > #include <linux/irqchip/arm-gic-common.h> > +#include <asm/kvm_mmu.h> > > #define PRODUCT_ID_KVM 0x4b /* ASCII code K */ > #define IMPLEMENTER_ARM 0x43b > @@ -126,6 +127,29 @@ static inline bool vgic_irq_is_multi_sgi(struct vgic_irq *irq) > return vgic_irq_get_lr_count(irq) > 1; > } > > +static inline int vgic_its_read_entry_lock(struct vgic_its *its, gpa_t eaddr, > + u64 *eval, unsigned long esize) > +{ > + struct kvm *kvm = its->dev->kvm; > + > + if (KVM_BUG_ON(esize != sizeof(*eval), kvm)) > + return -EINVAL; > + > + return kvm_read_guest_lock(kvm, eaddr, eval, esize); > + > +} > + > +static inline int vgic_its_write_entry_lock(struct vgic_its *its, gpa_t eaddr, > + u64 eval, unsigned long esize) > +{ > + struct kvm *kvm = its->dev->kvm; > + > + if (KVM_BUG_ON(esize != sizeof(eval), kvm)) > + return -EINVAL; > + > + return kvm_write_guest_lock(kvm, eaddr, &eval, esize); > +} > + > /* > * This struct provides an intermediate representation of the fields contained > * in the GICH_VMCR and ICH_VMCR registers, such that code exporting the GIC > > base-commit: cd5b619ac41b6b1a8167380ca6655df7ccf5b5eb > -- > 2.47.0.338.g60cca15819-goog >