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731ece41fb
This patch fixes a segfault in modpost that is observed when the gold linker is used to link the input objects. The problem is that reloc_location (modpost.c) is computing the address of the relocation target incorrectly. Here, elf->hdr points to the beginning of the ELF file in memory, sechdr points to the relocation section header, section is the index of the section being relocated, and sechdrs[section].sh_offset would be the offset of that section, relative to the beginning of the ELF file. Adding elf->hdr + sechdrs[section].sh_offset gives you the address of the beginning of the section, and adding r->r_offset to that gives you the address of the location to be relocated. You do not need to subtract sechdrs[section].sh_addr from that -- the result of this is an address outside the file, and causes the segfault when addend_386_rel tries to dereference it. This bug is not observed when GNU ld is used to link the inputs. The object file ubuntu/omnibook/omnibook.o is the result of an ld -r of several other files. When GNU ld does an ld -r, it sets the vaddr field for each section to 0, but gold lays out the section addresses sequentially instead: Section Headers: [Nr] Name Type Addr Off Size ES Flg Lk Inf Al [ 0] NULL 00000000 000000 000000 00 0 0 0 [ 1] .text PROGBITS 00000000 000034 004794 00 AX 0 0 4 [ 2] .data PROGBITS 0000b9d0 0047c8 0009c0 00 WA 0 0 4 [ 3] .bss NOBITS 000162f8 005188 00013c 00 WA 0 0 4 [ 4] .rodata.str1.1 PROGBITS 00004f2d 0052c4 001b1a 01 AMS 0 0 1 [ 5] .init.text PROGBITS 00004794 006dde 0005fa 00 AX 0 0 1 [ 6] .exit.text PROGBITS 00004d8e 0073d8 00018a 00 AX 0 0 1 ... So the bug in the tool remained undiscovered because the section's vaddr always happened to be 0. Signed-off-by: Raymes Khoury <raymes@google.com> Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Michal Marek <mmarek@suse.cz> |
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| .. | ||
| basic | ||
| coccinelle | ||
| dtc | ||
| genksyms | ||
| kconfig | ||
| ksymoops | ||
| mod | ||
| package | ||
| rt-tester | ||
| selinux | ||
| tracing | ||
| .gitignore | ||
| bin2c.c | ||
| bloat-o-meter | ||
| bootgraph.pl | ||
| checkincludes.pl | ||
| checkkconfigsymbols.sh | ||
| checkpatch.pl | ||
| checkstack.pl | ||
| checksyscalls.sh | ||
| checkversion.pl | ||
| cleanfile | ||
| cleanpatch | ||
| coccicheck | ||
| config | ||
| conmakehash.c | ||
| decodecode | ||
| diffconfig | ||
| export_report.pl | ||
| extract-ikconfig | ||
| gcc-goto.sh | ||
| gcc-version.sh | ||
| gcc-x86_32-has-stack-protector.sh | ||
| gcc-x86_64-has-stack-protector.sh | ||
| gen_initramfs_list.sh | ||
| get_maintainer.pl | ||
| gfp-translate | ||
| headerdep.pl | ||
| headers_check.pl | ||
| headers_install.pl | ||
| headers.sh | ||
| kallsyms.c | ||
| Kbuild.include | ||
| kernel-doc | ||
| Lindent | ||
| Makefile | ||
| Makefile.build | ||
| Makefile.clean | ||
| Makefile.fwinst | ||
| Makefile.headersinst | ||
| Makefile.help | ||
| Makefile.host | ||
| Makefile.lib | ||
| Makefile.modbuiltin | ||
| Makefile.modinst | ||
| Makefile.modpost | ||
| makelst | ||
| markup_oops.pl | ||
| mkcompile_h | ||
| mkmakefile | ||
| mksysmap | ||
| mkuboot.sh | ||
| mkversion | ||
| module-common.lds | ||
| namespace.pl | ||
| patch-kernel | ||
| pnmtologo.c | ||
| profile2linkerlist.pl | ||
| recordmcount.c | ||
| recordmcount.h | ||
| recordmcount.pl | ||
| setlocalversion | ||
| show_delta | ||
| tags.sh | ||
| unifdef.c | ||
| ver_linux | ||