diff options
| -rw-r--r-- | virt/kvm/arm/vgic/vgic-its.c | 134 |
1 files changed, 62 insertions, 72 deletions
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index dcae567c522d..996e3e19b53f 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -581,12 +581,73 @@ static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its, return 0; } +/* + * Check whether an ID can be stored into the corresponding guest table. + * For a direct table this is pretty easy, but gets a bit nasty for + * indirect tables. We check whether the resulting guest physical address + * is actually valid (covered by a memslot and guest accessbible). + * For this we have to read the respective first level entry. + */ +static bool vgic_its_check_id(struct vgic_its *its, u64 baser, int id) +{ + int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K; + int index; + u64 indirect_ptr; + gfn_t gfn; + + if (!(baser & GITS_BASER_INDIRECT)) { + phys_addr_t addr; + + if (id >= (l1_tbl_size / GITS_BASER_ENTRY_SIZE(baser))) + return false; + + addr = BASER_ADDRESS(baser) + id * GITS_BASER_ENTRY_SIZE(baser); + gfn = addr >> PAGE_SHIFT; + + return kvm_is_visible_gfn(its->dev->kvm, gfn); + } + + /* calculate and check the index into the 1st level */ + index = id / (SZ_64K / GITS_BASER_ENTRY_SIZE(baser)); + if (index >= (l1_tbl_size / sizeof(u64))) + return false; + + /* Each 1st level entry is represented by a 64-bit value. */ + if (kvm_read_guest(its->dev->kvm, + BASER_ADDRESS(baser) + index * sizeof(indirect_ptr), + &indirect_ptr, sizeof(indirect_ptr))) + return false; + + indirect_ptr = le64_to_cpu(indirect_ptr); + + /* check the valid bit of the first level entry */ + if (!(indirect_ptr & BIT_ULL(63))) + return false; + + /* + * Mask the guest physical address and calculate the frame number. + * Any address beyond our supported 48 bits of PA will be caught + * by the actual check in the final step. + */ + indirect_ptr &= GENMASK_ULL(51, 16); + + /* Find the address of the actual entry */ + index = id % (SZ_64K / GITS_BASER_ENTRY_SIZE(baser)); + indirect_ptr += index * GITS_BASER_ENTRY_SIZE(baser); + gfn = indirect_ptr >> PAGE_SHIFT; + + return kvm_is_visible_gfn(its->dev->kvm, gfn); +} + static int vgic_its_alloc_collection(struct vgic_its *its, struct its_collection **colp, u32 coll_id) { struct its_collection *collection; + if (!vgic_its_check_id(its, its->baser_coll_table, coll_id)) + return E_ITS_MAPC_COLLECTION_OOR; + collection = kzalloc(sizeof(*collection), GFP_KERNEL); collection->collection_id = coll_id; @@ -709,67 +770,6 @@ static void vgic_its_unmap_device(struct kvm *kvm, struct its_device *device) } /* - * Check whether a device ID can be stored into the guest device tables. - * For a direct table this is pretty easy, but gets a bit nasty for - * indirect tables. We check whether the resulting guest physical address - * is actually valid (covered by a memslot and guest accessbible). - * For this we have to read the respective first level entry. - */ -static bool vgic_its_check_device_id(struct kvm *kvm, struct vgic_its *its, - int device_id) -{ - u64 r = its->baser_device_table; - int l1_tbl_size = GITS_BASER_NR_PAGES(r) * SZ_64K; - int index; - u64 indirect_ptr; - gfn_t gfn; - - - if (!(r & GITS_BASER_INDIRECT)) { - phys_addr_t addr; - - if (device_id >= (l1_tbl_size / GITS_BASER_ENTRY_SIZE(r))) - return false; - - addr = BASER_ADDRESS(r) + device_id * GITS_BASER_ENTRY_SIZE(r); - gfn = addr >> PAGE_SHIFT; - - return kvm_is_visible_gfn(kvm, gfn); - } - - /* calculate and check the index into the 1st level */ - index = device_id / (SZ_64K / GITS_BASER_ENTRY_SIZE(r)); - if (index >= (l1_tbl_size / sizeof(u64))) - return false; - - /* Each 1st level entry is represented by a 64-bit value. */ - if (kvm_read_guest(kvm, - BASER_ADDRESS(r) + index * sizeof(indirect_ptr), - &indirect_ptr, sizeof(indirect_ptr))) - return false; - - indirect_ptr = le64_to_cpu(indirect_ptr); - - /* check the valid bit of the first level entry */ - if (!(indirect_ptr & BIT_ULL(63))) - return false; - - /* - * Mask the guest physical address and calculate the frame number. - * Any address beyond our supported 48 bits of PA will be caught - * by the actual check in the final step. - */ - indirect_ptr &= GENMASK_ULL(51, 16); - - /* Find the address of the actual entry */ - index = device_id % (SZ_64K / GITS_BASER_ENTRY_SIZE(r)); - indirect_ptr += index * GITS_BASER_ENTRY_SIZE(r); - gfn = indirect_ptr >> PAGE_SHIFT; - - return kvm_is_visible_gfn(kvm, gfn); -} - -/* * MAPD maps or unmaps a device ID to Interrupt Translation Tables (ITTs). * Must be called with the its_lock mutex held. */ @@ -780,7 +780,7 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, bool valid = its_cmd_get_validbit(its_cmd); struct its_device *device; - if (!vgic_its_check_device_id(kvm, its, device_id)) + if (!vgic_its_check_id(its, its->baser_device_table, device_id)) return E_ITS_MAPD_DEVICE_OOR; device = find_its_device(its, device_id); @@ -812,13 +812,6 @@ static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its, return 0; } -static int vgic_its_nr_collection_ids(struct vgic_its *its) -{ - u64 r = its->baser_coll_table; - - return (GITS_BASER_NR_PAGES(r) * SZ_64K) / GITS_BASER_ENTRY_SIZE(r); -} - /* * The MAPC command maps collection IDs to redistributors. * Must be called with the its_lock mutex held. @@ -838,9 +831,6 @@ static int vgic_its_cmd_handle_mapc(struct kvm *kvm, struct vgic_its *its, if (target_addr >= atomic_read(&kvm->online_vcpus)) return E_ITS_MAPC_PROCNUM_OOR; - if (coll_id >= vgic_its_nr_collection_ids(its)) - return E_ITS_MAPC_COLLECTION_OOR; - if (!valid) { vgic_its_free_collection(its, coll_id); } else { |
