ACPICA: actbl2: Replace 1-element arrays with flexible arrays

ACPICA commit 44f1af0664599e87bebc3a1260692baa27b2f264

Similar to "Replace one-element array with flexible-array", replace the
1-element array with a proper flexible array member as defined by C99.

This allows the code to operate without tripping compile-time and run-
time bounds checkers (e.g. via __builtin_object_size(), -fsanitize=bounds,
and/or -fstrict-flex-arrays=3).

The sizeof() uses with struct acpi_nfit_flush_address and struct
acpi_nfit_smbios have been adjusted to drop the open-coded subtraction
of the trailing single element. The result is no binary differences in
.text nor .data sections.

Link: https://github.com/acpica/acpica/commit/44f1af06
Signed-off-by: Bob Moore <robert.moore@intel.com>
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 4e48d6d..85d9d67 100644 (file)
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -894,7 +894,7 @@ static size_t sizeof_flush(struct acpi_nfit_flush_address *flush)
 {
        if (flush->header.length < sizeof(*flush))
                return 0;
-       return sizeof(*flush) + sizeof(u64) * (flush->hint_count - 1);
+       return struct_size(flush, hint_address, flush->hint_count);
 }
 
 static bool add_flush(struct acpi_nfit_desc *acpi_desc,
@@ -3477,7 +3477,7 @@ static __init int nfit_init(void)
        BUILD_BUG_ON(sizeof(struct acpi_nfit_system_address) != 64);
        BUILD_BUG_ON(sizeof(struct acpi_nfit_memory_map) != 48);
        BUILD_BUG_ON(sizeof(struct acpi_nfit_interleave) != 20);
-       BUILD_BUG_ON(sizeof(struct acpi_nfit_smbios) != 9);
+       BUILD_BUG_ON(sizeof(struct acpi_nfit_smbios) != 8);
        BUILD_BUG_ON(sizeof(struct acpi_nfit_control_region) != 80);
        BUILD_BUG_ON(sizeof(struct acpi_nfit_data_region) != 40);
        BUILD_BUG_ON(sizeof(struct acpi_nfit_capabilities) != 16);

diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index db292f3..6d3251e 100644 (file)
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -397,7 +397,7 @@ struct acpi_iort_node {
        u32 identifier;
        u32 mapping_count;
        u32 mapping_offset;
-       char node_data[1];
+       char node_data[];
 };
 
 /* Values for subtable Type above */
@@ -453,14 +453,14 @@ struct acpi_iort_memory_access {
  */
 struct acpi_iort_its_group {
        u32 its_count;
-       u32 identifiers[1];     /* GIC ITS identifier array */
+       u32 identifiers[];      /* GIC ITS identifier array */
 };
 
 struct acpi_iort_named_component {
        u32 node_flags;
        u64 memory_properties;  /* Memory access properties */
        u8 memory_address_limit;        /* Memory address size limit */
-       char device_name[1];    /* Path of namespace object */
+       char device_name[];     /* Path of namespace object */
 };
 
 /* Masks for Flags field above */
@@ -474,7 +474,7 @@ struct acpi_iort_root_complex {
        u32 pci_segment_number;
        u8 memory_address_limit;        /* Memory address size limit */
        u16 pasid_capabilities; /* PASID Capabilities */
-       u8 reserved[1];         /* Reserved, must be zero */
+       u8 reserved[];          /* Reserved, must be zero */
 };
 
 /* Masks for ats_attribute field above */
@@ -496,7 +496,7 @@ struct acpi_iort_smmu {
        u32 context_interrupt_offset;
        u32 pmu_interrupt_count;
        u32 pmu_interrupt_offset;
-       u64 interrupts[1];      /* Interrupt array */
+       u64 interrupts[];       /* Interrupt array */
 };
 
 /* Values for Model field above */
@@ -975,7 +975,7 @@ struct acpi_madt_local_sapic {
        u8 reserved[3];         /* Reserved, must be zero */
        u32 lapic_flags;
        u32 uid;                /* Numeric UID - ACPI 3.0 */
-       char uid_string[1];     /* String UID  - ACPI 3.0 */
+       char uid_string[];      /* String UID  - ACPI 3.0 */
 };
 
 /* 8: Platform Interrupt Source */
@@ -1708,7 +1708,7 @@ struct acpi_nfit_interleave {
 struct acpi_nfit_smbios {
        struct acpi_nfit_header header;
        u32 reserved;           /* Reserved, must be zero */
-       u8 data[1];             /* Variable length */
+       u8 data[];              /* Variable length */
 };
 
 /* 4: NVDIMM Control Region Structure */
@@ -1765,7 +1765,7 @@ struct acpi_nfit_flush_address {
        u32 device_handle;
        u16 hint_count;
        u8 reserved[6];         /* Reserved, must be zero */
-       u64 hint_address[1];    /* Variable length */
+       u64 hint_address[];     /* Variable length */
 };
 
 /* 7: Platform Capabilities Structure */

diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index c75abb4..745c4a2 100644 (file)
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -1878,14 +1878,14 @@ static size_t sizeof_spa(struct acpi_nfit_system_address *spa)
 static int nfit_test0_alloc(struct nfit_test *t)
 {
        struct acpi_nfit_system_address *spa = NULL;
+       struct acpi_nfit_flush_address *flush;
        size_t nfit_size = sizeof_spa(spa) * NUM_SPA
                        + sizeof(struct acpi_nfit_memory_map) * NUM_MEM
                        + sizeof(struct acpi_nfit_control_region) * NUM_DCR
                        + offsetof(struct acpi_nfit_control_region,
                                        window_size) * NUM_DCR
                        + sizeof(struct acpi_nfit_data_region) * NUM_BDW
-                       + (sizeof(struct acpi_nfit_flush_address)
-                                       + sizeof(u64) * NUM_HINTS) * NUM_DCR
+                       + struct_size(flush, hint_address, NUM_HINTS) * NUM_DCR
                        + sizeof(struct acpi_nfit_capabilities);
        int i;