From b370a5e979f8bb8f34e30ad126ade734d8f128c0 Mon Sep 17 00:00:00 2001 From: Mostafa Saleh Date: Thu, 24 Sep 2026 08:56:16 +0000 Subject: [PATCH] iommu/arm-smmu-v3-test: Fix UBSAN error struct arm_smmu_invs marks its flexible array member inv[] with the __counted_by(max_invs). arm_smmu_v3_invs_test() uses invs1 to invs5 which has num_invs = 3 but omit max_invs. This causes the following UBSAN error: [ 2.333240] UBSAN: array-index-out-of-bounds in drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c:1116:21 [ 2.333604] # arm_smmu_v3_invs_test: lib/ubsan.c:228: array-index-out-of-bounds in drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c [ 2.334129] index 1 is out of range for type 'struct arm_smmu_inv[] __counted_by(max_invs)' (aka 'struct arm_smmu_inv[]') [ 2.335375] CPU: 6 UID: 0 PID: 155 Comm: kunit_try_catch Tainted: G N 7.2.0-g8dcb331fbb72 #2 PREEMPT [ 2.335759] Tainted: [N]=TEST [ 2.335791] Hardware name: linux,dummy-virt (DT) [ 2.336254] Call trace: [ 2.336932] show_stack+0x18/0x24 (C) [ 2.338443] __dump_stack+0x28/0x38 [ 2.338494] dump_stack_lvl+0x54/0x6c [ 2.338518] dump_stack+0x18/0x24 [ 2.338541] ubsan_epilogue+0x10/0x44 [ 2.338565] __ubsan_handle_out_of_bounds+0xb8/0xbc [ 2.338834] arm_smmu_invs_merge+0x688/0x8ac [ 2.338862] arm_smmu_v3_invs_test+0xd4/0x598 [ 2.338890] kunit_try_run_case+0x64/0x160 [ 2.338914] kunit_generic_run_threadfn_adapter+0x28/0x4c [ 2.338955] kthread+0x10c/0x12c [ 2.338984] ret_from_fork+0x10/0x20 [ 2.339433] ---[ end trace ]--- Explicitly set max_invs = 3 on the test arrays to match the number of elements. Fixes: 15a2a5645ad7 ("iommu/arm-smmu-v3: Introduce a per-domain arm_smmu_invs array") Reviewed-by: Nicolin Chen Reviewed-by: Jason Gunthorpe Signed-off-by: Mostafa Saleh Reviewed-by: Pranjal Shrivastava Tested-by: Nicolin Chen Signed-off-by: Will Deacon --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c index 244cf34e5a0b..e52a7d95c919 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c @@ -654,6 +654,7 @@ static void arm_smmu_v3_invs_test_verify(struct kunit *test, } static struct arm_smmu_invs invs1 = { + .max_invs = 3, .num_invs = 3, .inv = { { .type = INV_TYPE_S2_VMID, .id = 1, }, { .type = INV_TYPE_S2_VMID_S1_CLEAR, .id = 1, }, @@ -661,6 +662,7 @@ static struct arm_smmu_invs invs1 = { }; static struct arm_smmu_invs invs2 = { + .max_invs = 3, .num_invs = 3, .inv = { { .type = INV_TYPE_S2_VMID, .id = 1, }, /* duplicated */ { .type = INV_TYPE_ATS, .id = 4, }, @@ -668,6 +670,7 @@ static struct arm_smmu_invs invs2 = { }; static struct arm_smmu_invs invs3 = { + .max_invs = 3, .num_invs = 3, .inv = { { .type = INV_TYPE_S2_VMID, .id = 1, }, /* duplicated */ { .type = INV_TYPE_ATS, .id = 5, }, /* recover a trash */ @@ -675,6 +678,7 @@ static struct arm_smmu_invs invs3 = { }; static struct arm_smmu_invs invs4 = { + .max_invs = 3, .num_invs = 3, .inv = { { .type = INV_TYPE_ATS, .id = 10, .ssid = 1 }, { .type = INV_TYPE_ATS, .id = 10, .ssid = 3 }, @@ -682,6 +686,7 @@ static struct arm_smmu_invs invs4 = { }; static struct arm_smmu_invs invs5 = { + .max_invs = 3, .num_invs = 3, .inv = { { .type = INV_TYPE_ATS, .id = 10, .ssid = 2 }, { .type = INV_TYPE_ATS, .id = 10, .ssid = 3 }, /* duplicate */