Cap end of relocations by the binary size.
Linkers like to insert some auxiliary sections between .rela.dyn and .bss_start. These sections don't make their way to the final binary, but reloc_rela still tries to relocate them, resulting in attempted read past the end of file.
When linking U-Boot with ld.lld, the STATIC_RELA feature (enabled by default on arm64) breaks the build. After this patch, U-Boot can be linked successfully with and without CONFIG_STATIC_RELA.
Originally-from: Elena Petrova lenaptr@google.com Signed-off-by: Alistair Delva adelva@google.com Cc: David Brazdil dbrazdil@google.com Cc: Scott Wood scottwood@freescale.com Cc: Tom Rini trini@konsulko.com --- tools/relocate-rela.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/tools/relocate-rela.c b/tools/relocate-rela.c index 6a524014b7..f0bc548617 100644 --- a/tools/relocate-rela.c +++ b/tools/relocate-rela.c @@ -63,7 +63,7 @@ int main(int argc, char **argv) { FILE *f; int i, num; - uint64_t rela_start, rela_end, text_base; + uint64_t rela_start, rela_end, text_base, file_size;
if (argc != 5) { fprintf(stderr, "Statically apply ELF rela relocations\n"); @@ -87,8 +87,7 @@ int main(int argc, char **argv) return 3; }
- if (rela_start > rela_end || rela_start < text_base || - (rela_end - rela_start) % sizeof(Elf64_Rela)) { + if (rela_start > rela_end || rela_start < text_base) { fprintf(stderr, "%s: bad rela bounds\n", argv[0]); return 3; } @@ -96,6 +95,21 @@ int main(int argc, char **argv) rela_start -= text_base; rela_end -= text_base;
+ fseek(f, 0, SEEK_END); + file_size = ftell(f); + rewind(f); + + if (rela_end > file_size) { + // Most likely compiler inserted some section that didn't get + // objcopy-ed into the final binary + rela_end = file_size; + } + + if ((rela_end - rela_start) % sizeof(Elf64_Rela)) { + fprintf(stderr, "%s: rela size isn't a multiple of Elf64_Rela\n", argv[0]); + return 3; + } + num = (rela_end - rela_start) / sizeof(Elf64_Rela);
for (i = 0; i < num; i++) {