Re: Unreachable code in mkimagexx (Fwd: New Defects reported by Coverity Scan for GRUB)

[Andrei Borzenkov]

On Sun, Mar 13, 2016 at 10:38 AM, Andrei Borzenkov <address@hidden> wrote:
>
> We probably need to #ifdef this section for MKIMAGE_ELF64 case only, it
> makes no sense to compile it for 32 bit target.
>

Hmm ... why translate_relocation_pe, translate_relocation_raw and
classify_raw_reloc are not target size specific in the first place?
They take Elf_Addr parameters so cannot work for both 32 and 64 bit
targets at the same time.




> ________________________________________________________________________________________________________
> *** CID 158599:    (DEADCODE)
> /util/grub-mkimagexx.c: 1317 in translate_relocation_pe()
> 1311              break;
> 1312            }
> 1313           break;
> 1314         case EM_AARCH64:
> 1315           switch (ELF_R_TYPE (info))
> 1316            {
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 257U:".
> 1317            case R_AARCH64_ABS64:
> 1318              {
> 1319                ctx->current_address
> 1320                  = add_fixup_entry (&ctx->lst,
> 1321                                     GRUB_PE32_REL_BASED_DIR64,
> 1322                                     addr, 0, ctx->current_address,
> /util/grub-mkimagexx.c: 1331 in translate_relocation_pe()
> 1325              break;
> 1326              /* Relative relocations do not require fixup entries. */
> 1327            case R_AARCH64_CALL26:
> 1328            case R_AARCH64_JUMP26:
> 1329              break;
> 1330              /* Page-relative relocations do not require fixup entries. 
> */
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 275U:".
> 1331            case R_AARCH64_ADR_PREL_PG_HI21:
> 1332              /* We page-align the whole kernel, so no need
> 1333                 for fixup entries.
> 1334              */
> 1335            case R_AARCH64_ADD_ABS_LO12_NC:
> 1336            case R_AARCH64_LDST64_ABS_LO12_NC:
> /util/grub-mkimagexx.c: 1335 in translate_relocation_pe()
> 1329              break;
> 1330              /* Page-relative relocations do not require fixup entries. 
> */
> 1331            case R_AARCH64_ADR_PREL_PG_HI21:
> 1332              /* We page-align the whole kernel, so no need
> 1333                 for fixup entries.
> 1334              */
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 277U:".
> 1335            case R_AARCH64_ADD_ABS_LO12_NC:
> 1336            case R_AARCH64_LDST64_ABS_LO12_NC:
> 1337              break;
> 1338
> 1339            default:
> 1340              grub_util_error (_("relocation 0x%x is not implemented 
> yet"),
> /util/grub-mkimagexx.c: 1328 in translate_relocation_pe()
> 1322                                     addr, 0, ctx->current_address,
> 1323                                     image_target);
> 1324              }
> 1325              break;
> 1326              /* Relative relocations do not require fixup entries. */
> 1327            case R_AARCH64_CALL26:
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 282U:".
> 1328            case R_AARCH64_JUMP26:
> 1329              break;
> 1330              /* Page-relative relocations do not require fixup entries. 
> */
> 1331            case R_AARCH64_ADR_PREL_PG_HI21:
> 1332              /* We page-align the whole kernel, so no need
> 1333                 for fixup entries.
> /util/grub-mkimagexx.c: 1327 in translate_relocation_pe()
> 1321                                     GRUB_PE32_REL_BASED_DIR64,
> 1322                                     addr, 0, ctx->current_address,
> 1323                                     image_target);
> 1324              }
> 1325              break;
> 1326              /* Relative relocations do not require fixup entries. */
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 283U:".
> 1327            case R_AARCH64_CALL26:
> 1328            case R_AARCH64_JUMP26:
> 1329              break;
> 1330              /* Page-relative relocations do not require fixup entries. 
> */
> 1331            case R_AARCH64_ADR_PREL_PG_HI21:
> 1332              /* We page-align the whole kernel, so no need
> /util/grub-mkimagexx.c: 1336 in translate_relocation_pe()
> 1330              /* Page-relative relocations do not require fixup entries. 
> */
> 1331            case R_AARCH64_ADR_PREL_PG_HI21:
> 1332              /* We page-align the whole kernel, so no need
> 1333                 for fixup entries.
> 1334              */
> 1335            case R_AARCH64_ADD_ABS_LO12_NC:
>>>>     CID 158599:    (DEADCODE)
>>>>     Execution cannot reach this statement: "case 286U:".
> 1336            case R_AARCH64_LDST64_ABS_LO12_NC:
> 1337              break;
> 1338
> 1339            default:
> 1340              grub_util_error (_("relocation 0x%x is not implemented 
> yet"),
> 1341                               (unsigned int) ELF_R_TYPE (info));
>
>