commit 1d00e5ce0fb069911c4b525ec38289fb5d9021b0 Author: Paul Floyd Date: Sat Nov 18 08:49:34 2023 +0100 Bug 476548 - valgrind 3.22.0 fails on assertion when loading debuginfo file produced by mold (cherry picked from commit 9ea4ae66707a4dcc6f4328e11911652e4418c585) diff --git a/coregrind/m_debuginfo/image.c b/coregrind/m_debuginfo/image.c index 02e509071..445f95555 100644 --- a/coregrind/m_debuginfo/image.c +++ b/coregrind/m_debuginfo/image.c @@ -1221,6 +1221,20 @@ Int ML_(img_strcmp_c)(DiImage* img, DiOffT off1, const HChar* str2) } } +Int ML_(img_strcmp_n)(DiImage* img, DiOffT off1, const HChar* str2, Word n) +{ + ensure_valid(img, off1, 1, "ML_(img_strcmp_c)"); + while (n) { + UChar c1 = get(img, off1); + UChar c2 = *(const UChar*)str2; + if (c1 < c2) return -1; + if (c1 > c2) return 1; + if (c1 == 0) return 0; + off1++; str2++; --n; + } + return 0; +} + UChar ML_(img_get_UChar)(DiImage* img, DiOffT offset) { ensure_valid(img, offset, 1, "ML_(img_get_UChar)"); diff --git a/coregrind/m_debuginfo/priv_image.h b/coregrind/m_debuginfo/priv_image.h index a49846f14..c91e49f01 100644 --- a/coregrind/m_debuginfo/priv_image.h +++ b/coregrind/m_debuginfo/priv_image.h @@ -115,6 +115,10 @@ Int ML_(img_strcmp)(DiImage* img, DiOffT off1, DiOffT off2); cast to HChar before comparison. */ Int ML_(img_strcmp_c)(DiImage* img, DiOffT off1, const HChar* str2); +/* Do strncmp of a C string in the image vs a normal one. Chars are + cast to HChar before comparison. */ +Int ML_(img_strcmp_n)(DiImage* img, DiOffT off1, const HChar* str2, Word n); + /* Do strlen of a C string in the image. */ SizeT ML_(img_strlen)(DiImage* img, DiOffT off); diff --git a/coregrind/m_debuginfo/readelf.c b/coregrind/m_debuginfo/readelf.c index fb64ed976..46f8c8343 100644 --- a/coregrind/m_debuginfo/readelf.c +++ b/coregrind/m_debuginfo/readelf.c @@ -2501,8 +2501,7 @@ Bool ML_(read_elf_object) ( struct _DebugInfo* di ) di->rodata_avma += inrw1->bias; di->rodata_bias = inrw1->bias; di->rodata_debug_bias = inrw1->bias; - } - else { + } else { BAD(".rodata"); /* should not happen? */ } di->rodata_present = True; @@ -2977,6 +2976,46 @@ Bool ML_(read_elf_object) ( struct _DebugInfo* di ) return retval; } +static void find_rodata(Word i, Word shnum, DiImage* dimg, struct _DebugInfo* di, DiOffT shdr_dioff, + UWord shdr_dent_szB, DiOffT shdr_strtab_dioff, PtrdiffT rw_dbias) +{ + ElfXX_Shdr a_shdr; + ElfXX_Shdr a_extra_shdr; + ML_(img_get)(&a_shdr, dimg, + INDEX_BIS(shdr_dioff, i, shdr_dent_szB), + sizeof(a_shdr)); + if (di->rodata_present && + 0 == ML_(img_strcmp_c)(dimg, shdr_strtab_dioff + + a_shdr.sh_name, ".rodata")) { + Word sh_size = a_shdr.sh_size; + Word j; + Word next_addr = a_shdr.sh_addr + a_shdr.sh_size; + for (j = i + 1; j < shnum; ++j) { + ML_(img_get)(&a_extra_shdr, dimg, + INDEX_BIS(shdr_dioff, j, shdr_dent_szB), + sizeof(a_shdr)); + if (0 == ML_(img_strcmp_n)(dimg, shdr_strtab_dioff + + a_extra_shdr.sh_name, ".rodata", 7)) { + if (a_extra_shdr.sh_addr == + VG_ROUNDUP(next_addr, a_extra_shdr.sh_addralign)) { + sh_size = VG_ROUNDUP(sh_size, a_extra_shdr.sh_addralign) + a_extra_shdr.sh_size; + } + next_addr = a_extra_shdr.sh_addr + a_extra_shdr.sh_size; + } else { + break; + } + } + vg_assert(di->rodata_size == sh_size); + vg_assert(di->rodata_avma + a_shdr.sh_addr + rw_dbias); + di->rodata_debug_svma = a_shdr.sh_addr; + di->rodata_debug_bias = di->rodata_bias + + di->rodata_svma - di->rodata_debug_svma; + TRACE_SYMTAB("acquiring .rodata debug svma = %#lx .. %#lx\n", + di->rodata_debug_svma, + di->rodata_debug_svma + di->rodata_size - 1); + TRACE_SYMTAB("acquiring .rodata debug bias = %#lx\n", (UWord)di->rodata_debug_bias); + } +} Bool ML_(read_elf_debug) ( struct _DebugInfo* di ) { Word i, j; @@ -3391,7 +3430,11 @@ Bool ML_(read_elf_debug) ( struct _DebugInfo* di ) FIND(text, rx) FIND(data, rw) FIND(sdata, rw) - FIND(rodata, rw) + // https://bugs.kde.org/show_bug.cgi?id=476548 + // special handling for rodata as adjacent + // rodata sections may have been merged in ML_(read_elf_object) + //FIND(rodata, rw) + find_rodata(i, ehdr_dimg.e_shnum, dimg, di, shdr_dioff, shdr_dent_szB, shdr_strtab_dioff, rw_dbias); FIND(bss, rw) FIND(sbss, rw)