Hello Erik Kaneda,
The patch cefc7ca46235: "ACPI: PRM: implement OperationRegion handler
for the PlatformRtMechanism subtype" from Jun 9, 2021, leads to the
following static checker warning:
drivers/acpi/prmt.c:113 acpi_parse_prmt()
error: potential null dereference 'tm'. (kmalloc returns null)
drivers/acpi/prmt.c
95 static int __init
96 acpi_parse_prmt(union acpi_subtable_headers *header, const unsigned long end)
97 {
98 struct acpi_prmt_module_info *module_info;
99 struct acpi_prmt_handler_info *handler_info;
100 struct prm_handler_info *th;
101 struct prm_module_info *tm;
102 u64 mmio_count = 0;
103 u64 cur_handler = 0;
104 u32 module_info_size = 0;
105 u64 mmio_range_size = 0;
106 void *temp_mmio;
107
108 module_info = (struct acpi_prmt_module_info *) header;
109 module_info_size = struct_size(tm, handlers, module_info->handler_info_count);
110 tm = kmalloc(module_info_size, GFP_KERNEL);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Check for NULL?
111
112 guid_copy(&tm->guid, (guid_t *) module_info->module_guid);
113 tm->major_rev = module_info->major_rev;
114 tm->minor_rev = module_info->minor_rev;
115 tm->handler_count = module_info->handler_info_count;
116 tm->updatable = true;
117
118 if (module_info->mmio_list_pointer) {
119 /*
120 * Each module is associated with a list of addr
121 * ranges that it can use during the service
122 */
123 mmio_count = *(u64 *) memremap(module_info->mmio_list_pointer, 8, MEMREMAP_WB);
124 mmio_range_size = struct_size(tm->mmio_info, addr_ranges, mmio_count);
125 tm->mmio_info = kmalloc(mmio_range_size, GFP_KERNEL);
126 temp_mmio = memremap(module_info->mmio_list_pointer, mmio_range_size, MEMREMAP_WB);
127 memmove(tm->mmio_info, temp_mmio, mmio_range_size);
128 } else {
129 mmio_range_size = struct_size(tm->mmio_info, addr_ranges, mmio_count);
130 tm->mmio_info = kmalloc(mmio_range_size, GFP_KERNEL);
131 tm->mmio_info->mmio_count = 0;
132 }
133
134 INIT_LIST_HEAD(&tm->module_list);
135 list_add(&tm->module_list, &prm_module_list);
regards,
dan carpenter
