Re: Fwd: New Defects reported by Coverity Scan for Das U-Boot

Heinrich Schuchardt
2024-01-27T20:56:13Z

Am 27. Januar 2024 16:40:18 MEZ schrieb Tom Rini <trini@konsulko.com>:
>Hey, I'll just pass this on directly rather than to the list.
>
>---------- Forwarded message ---------
>From: <scan-admin@coverity.com>
>Date: Sat, Jan 27, 2024 at 10:36 AM
>Subject: New Defects reported by Coverity Scan for Das U-Boot
>To: <tom.rini@gmail.com>
>
>
>Hi,
>
>Please find the latest report on new defect(s) introduced to Das
>U-Boot found with Coverity Scan.
>
>1 new defect(s) introduced to Das U-Boot found with Coverity Scan.
>
>
>New defect(s) Reported-by: Coverity Scan
>Showing 1 of 1 defect(s)
>
>
>** CID 479279: (TAINTED_SCALAR)
>
>
>________________________________________________________________________________________________________
>*** CID 479279: (TAINTED_SCALAR)
>/cmd/smbios.c: 180 in do_smbios()
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "pos->length" to "smbios_print_generic", which uses it as a loop boundary.
>180 smbios_print_generic(pos);
>181 break;
>182 }
>183 }
>184
>185 return CMD_RET_SUCCESS;
>/cmd/smbios.c: 154 in do_smbios()
>148 size = entry2->length;
>149 max_struct_size = entry2->max_struct_size;
>150 } else {
>151 log_err("Unknown SMBIOS anchor format\n");
>152 return CMD_RET_FAILURE;
>153 }
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "size" to "table_compute_checksum", which uses it as a loop boundary.
>154 if (table_compute_checksum(entry, size)) {
>155 log_err("Invalid anchor checksum\n");
>156 return CMD_RET_FAILURE;
>157 }
>158 printf("SMBIOS %s present.\n", version);
>159
>/cmd/smbios.c: 174 in do_smbios()
>168 (unsigned long long)map_to_sysmem(pos));
>169 switch (pos->type) {
>170 case 1:
>171 smbios_print_type1((struct smbios_type1 *)pos);
>172 break;
>173 case 2:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "((struct smbios_type2 *)pos)->number_contained_objects" to "smbios_print_type2", which uses it as a loop boundary.
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>/cmd/smbios.c: 154 in do_smbios()
>148 size = entry2->length;
>149 max_struct_size = entry2->max_struct_size;
>150 } else {
>151 log_err("Unknown SMBIOS anchor format\n");
>152 return CMD_RET_FAILURE;
>153 }
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "size" to "table_compute_checksum", which uses it as a loop boundary.
>154 if (table_compute_checksum(entry, size)) {
>155 log_err("Invalid anchor checksum\n");
>156 return CMD_RET_FAILURE;
>157 }
>158 printf("SMBIOS %s present.\n", version);
>159
>/cmd/smbios.c: 180 in do_smbios()
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "pos->length" to "smbios_print_generic", which uses it as a loop boundary.
>180 smbios_print_generic(pos);
>181 break;
>182 }
>183 }
>184
>185 return CMD_RET_SUCCESS;
>/cmd/smbios.c: 174 in do_smbios()
>168 (unsigned long long)map_to_sysmem(pos));
>169 switch (pos->type) {
>170 case 1:
>171 smbios_print_type1((struct smbios_type1 *)pos);
>172 break;
>173 case 2:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "((struct smbios_type2 *)pos)->number_contained_objects" to "smbios_print_type2", which uses it as a loop boundary.
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>/cmd/smbios.c: 174 in do_smbios()
>168 (unsigned long long)map_to_sysmem(pos));
>169 switch (pos->type) {
>170 case 1:
>171 smbios_print_type1((struct smbios_type1 *)pos);
>172 break;
>173 case 2:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "((struct smbios_type2 *)pos)->number_contained_objects" to "smbios_print_type2", which uses it as a loop boundary.
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>/cmd/smbios.c: 180 in do_smbios()
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "pos->length" to "smbios_print_generic", which uses it as a loop boundary.
>180 smbios_print_generic(pos);
>181 break;
>182 }
>183 }
>184
>185 return CMD_RET_SUCCESS;
>/cmd/smbios.c: 180 in do_smbios()
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "pos->length" to "smbios_print_generic", which uses it as a loop boundary.
>180 smbios_print_generic(pos);
>181 break;
>182 }
>183 }
>184
>185 return CMD_RET_SUCCESS;
>/cmd/smbios.c: 174 in do_smbios()
>168 (unsigned long long)map_to_sysmem(pos));
>169 switch (pos->type) {
>170 case 1:
>171 smbios_print_type1((struct smbios_type1 *)pos);
>172 break;
>173 case 2:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "((struct smbios_type2 *)pos)->number_contained_objects" to "smbios_print_type2", which uses it as a loop boundary.
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>/cmd/smbios.c: 180 in do_smbios()
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "pos->length" to "smbios_print_generic", which uses it as a loop boundary.
>180 smbios_print_generic(pos);
>181 break;
>182 }
>183 }
>184
>185 return CMD_RET_SUCCESS;
>/cmd/smbios.c: 174 in do_smbios()
>168 (unsigned long long)map_to_sysmem(pos));
>169 switch (pos->type) {
>170 case 1:
>171 smbios_print_type1((struct smbios_type1 *)pos);
>172 break;
>173 case 2:
>>>> CID 479279: (TAINTED_SCALAR)
>>>> Passing tainted expression "((struct smbios_type2 *)pos)->number_contained_objects" to "smbios_print_type2", which uses it as a loop boundary.
>174 smbios_print_type2((struct smbios_type2 *)pos);
>175 break;
>176 case 127:
>177 smbios_print_type127((struct
>smbios_type127 *)pos);
>178 break;
>179 default:
>

The values may come from QEMU, so may be "tainted". We could check the length of the individual structures against the total size of the SMBIOS table.

Best regards

Heinrich