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Diffstat (limited to 'src/elflint.c')
-rw-r--r--src/elflint.c348
1 files changed, 308 insertions, 40 deletions
diff --git a/src/elflint.c b/src/elflint.c
index cd335fe6..a679acc4 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -951,14 +951,14 @@ section [%2d] '%s': _DYNAMIC symbol size %" PRIu64 " does not match dynamic segm
static bool
is_rel_dyn (Ebl *ebl, const GElf_Ehdr *ehdr, int idx, const GElf_Shdr *shdr,
- bool rela)
+ bool is_rela)
{
/* If this is no executable or DSO it cannot be a .rel.dyn section. */
if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN)
return false;
/* Check the section name. Unfortunately necessary. */
- if (strcmp (section_name (ebl, idx), rela ? ".rela.dyn" : ".rel.dyn"))
+ if (strcmp (section_name (ebl, idx), is_rela ? ".rela.dyn" : ".rel.dyn"))
return false;
/* When a .rel.dyn section is used a DT_RELCOUNT dynamic section
@@ -984,14 +984,106 @@ is_rel_dyn (Ebl *ebl, const GElf_Ehdr *ehdr, int idx, const GElf_Shdr *shdr,
if (dyn->d_tag == DT_RELCOUNT)
{
- /* Found it. One last check: does the number
- specified number of relative relocations exceed
- the total number of relocations? */
- if (dyn->d_un.d_val > shdr->sh_size / shdr->sh_entsize)
+ /* Found it. Does the type match. */
+ if (is_rela)
ERROR (gettext ("\
+section [%2d] '%s': DT_RELCOUNT used for this RELA section\n"),
+ idx, section_name (ebl, idx));
+ else
+ {
+ /* Does the number specified number of relative
+ relocations exceed the total number of
+ relocations? */
+ if (dyn->d_un.d_val > shdr->sh_size / shdr->sh_entsize)
+ ERROR (gettext ("\
section [%2d] '%s': DT_RELCOUNT value %d too high for this section\n"),
- idx, section_name (ebl, idx),
- (int) dyn->d_un.d_val);
+ idx, section_name (ebl, idx),
+ (int) dyn->d_un.d_val);
+
+ /* Make sure the specified number of relocations are
+ relative. */
+ Elf_Data *reldata = elf_getdata (elf_getscn (ebl->elf,
+ idx), NULL);
+ if (reldata != NULL)
+ for (size_t inner = 0;
+ inner < shdr->sh_size / shdr->sh_entsize;
+ ++inner)
+ {
+ GElf_Rel rel_mem;
+ GElf_Rel *rel = gelf_getrel (reldata, inner,
+ &rel_mem);
+ if (rel == NULL)
+ /* The problem will be reported elsewhere. */
+ break;
+
+ if (ebl_relative_reloc_p (ebl,
+ GELF_R_TYPE (rel->r_info)))
+ {
+ if (inner >= dyn->d_un.d_val)
+ ERROR (gettext ("\
+section [%2d] '%s': relative relocations after index %d as specified by DT_RELCOUNT\n"),
+ idx, section_name (ebl, idx),
+ (int) dyn->d_un.d_val);
+ }
+ else if (inner < dyn->d_un.d_val)
+ ERROR (gettext ("\
+section [%2d] '%s': non-relative relocation at index %zu; DT_RELCOUNT specified %d relative relocations\n"),
+ idx, section_name (ebl, idx),
+ inner, (int) dyn->d_un.d_val);
+ }
+ }
+ }
+
+ if (dyn->d_tag == DT_RELACOUNT)
+ {
+ /* Found it. Does the type match. */
+ if (!is_rela)
+ ERROR (gettext ("\
+section [%2d] '%s': DT_RELACOUNT used for this REL section\n"),
+ idx, section_name (ebl, idx));
+ else
+ {
+ /* Does the number specified number of relative
+ relocations exceed the total number of
+ relocations? */
+ if (dyn->d_un.d_val > shdr->sh_size / shdr->sh_entsize)
+ ERROR (gettext ("\
+section [%2d] '%s': DT_RELCOUNT value %d too high for this section\n"),
+ idx, section_name (ebl, idx),
+ (int) dyn->d_un.d_val);
+
+ /* Make sure the specified number of relocations are
+ relative. */
+ Elf_Data *reldata = elf_getdata (elf_getscn (ebl->elf,
+ idx), NULL);
+ if (reldata != NULL)
+ for (size_t inner = 0;
+ inner < shdr->sh_size / shdr->sh_entsize;
+ ++inner)
+ {
+ GElf_Rela rela_mem;
+ GElf_Rela *rela = gelf_getrela (reldata, inner,
+ &rela_mem);
+ if (rela == NULL)
+ /* The problem will be reported elsewhere. */
+ break;
+
+ if (ebl_relative_reloc_p (ebl,
+ GELF_R_TYPE (rela->r_info)))
+ {
+ if (inner >= dyn->d_un.d_val)
+ ERROR (gettext ("\
+section [%2d] '%s': relative relocations after index %d as specified by DT_RELCOUNT\n"),
+ idx, section_name (ebl, idx),
+ (int) dyn->d_un.d_val);
+ }
+ else if (inner < dyn->d_un.d_val)
+ ERROR (gettext ("\
+section [%2d] '%s': non-relative relocation at index %zu; DT_RELCOUNT specified %d relative relocations\n"),
+ idx, section_name (ebl, idx),
+ inner, (int) dyn->d_un.d_val);
+ }
+ }
}
}
@@ -1718,7 +1810,194 @@ extended section index is %" PRIu32 " but symbol index is not XINDEX\n"),
static void
-check_hash (Ebl *ebl, GElf_Ehdr *ehdr, GElf_Shdr *shdr, int idx)
+check_sysv_hash (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *data, int idx,
+ GElf_Shdr *symshdr)
+{
+ Elf32_Word nbucket = ((Elf32_Word *) data->d_buf)[0];
+ Elf32_Word nchain = ((Elf32_Word *) data->d_buf)[1];
+
+ if (shdr->sh_size < (2 + nbucket + nchain) * shdr->sh_entsize)
+ ERROR (gettext ("\
+section [%2d] '%s': hash table section is too small (is %ld, expected %ld)\n"),
+ idx, section_name (ebl, idx), (long int) shdr->sh_size,
+ (long int) ((2 + nbucket + nchain) * shdr->sh_entsize));
+
+ size_t maxidx = nchain;
+
+ if (symshdr != NULL)
+ {
+ size_t symsize = symshdr->sh_size / symshdr->sh_entsize;
+
+ if (nchain > symshdr->sh_size / symshdr->sh_entsize)
+ ERROR (gettext ("section [%2d] '%s': chain array too large\n"),
+ idx, section_name (ebl, idx));
+
+ maxidx = symsize;
+ }
+
+ size_t cnt;
+ for (cnt = 2; cnt < 2 + nbucket; ++cnt)
+ if (((Elf32_Word *) data->d_buf)[cnt] >= maxidx)
+ ERROR (gettext ("\
+section [%2d] '%s': hash bucket reference %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt - 2);
+
+ for (; cnt < 2 + nbucket + nchain; ++cnt)
+ if (((Elf32_Word *) data->d_buf)[cnt] >= maxidx)
+ ERROR (gettext ("\
+section [%2d] '%s': hash chain reference %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt - 2 - nbucket);
+}
+
+
+static void
+check_sysv_hash64 (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *data, int idx,
+ GElf_Shdr *symshdr)
+{
+ Elf64_Xword nbucket = ((Elf64_Xword *) data->d_buf)[0];
+ Elf64_Xword nchain = ((Elf64_Xword *) data->d_buf)[1];
+
+ if (shdr->sh_size < (2 + nbucket + nchain) * shdr->sh_entsize)
+ ERROR (gettext ("\
+section [%2d] '%s': hash table section is too small (is %ld, expected %ld)\n"),
+ idx, section_name (ebl, idx), (long int) shdr->sh_size,
+ (long int) ((2 + nbucket + nchain) * shdr->sh_entsize));
+
+ size_t maxidx = nchain;
+
+ if (symshdr != NULL)
+ {
+ size_t symsize = symshdr->sh_size / symshdr->sh_entsize;
+
+ if (nchain > symshdr->sh_size / symshdr->sh_entsize)
+ ERROR (gettext ("section [%2d] '%s': chain array too large\n"),
+ idx, section_name (ebl, idx));
+
+ maxidx = symsize;
+ }
+
+ size_t cnt;
+ for (cnt = 2; cnt < 2 + nbucket; ++cnt)
+ if (((Elf64_Xword *) data->d_buf)[cnt] >= maxidx)
+ ERROR (gettext ("\
+section [%2d] '%s': hash bucket reference %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt - 2);
+
+ for (; cnt < 2 + nbucket + nchain; ++cnt)
+ if (((Elf64_Xword *) data->d_buf)[cnt] >= maxidx)
+ ERROR (gettext ("\
+section [%2d] '%s': hash chain reference %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt - 2 - nbucket);
+}
+
+
+static void
+check_gnu_hash (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *data, int idx,
+ GElf_Shdr *symshdr)
+{
+ Elf32_Word nbuckets = ((Elf32_Word *) data->d_buf)[0];
+ Elf32_Word symbias = ((Elf32_Word *) data->d_buf)[1];
+
+ if (shdr->sh_size < (2 + 2 * nbuckets) * sizeof (Elf32_Word))
+ {
+ ERROR (gettext ("\
+section [%2d] '%s': hash table section is too small (is %ld, expected at least%ld)\n"),
+ idx, section_name (ebl, idx), (long int) shdr->sh_size,
+ (long int) ((2 + 2 * nbuckets) * sizeof (Elf32_Word)));
+ return;
+ }
+
+ size_t maxidx = shdr->sh_size / sizeof (Elf32_Word) - (2 + 2 * nbuckets);
+
+ if (symshdr != NULL)
+ maxidx = MIN (maxidx, symshdr->sh_size / symshdr->sh_entsize);
+
+ /* We need the symbol section data. */
+ Elf_Data *symdata = elf_getdata (elf_getscn (ebl->elf, shdr->sh_link), NULL);
+
+ size_t cnt;
+ for (cnt = 2; cnt < 2 + 2 * nbuckets; cnt += 2)
+ {
+ Elf32_Word bitset = ((Elf32_Word *) data->d_buf)[cnt];
+ Elf32_Word symidx = ((Elf32_Word *) data->d_buf)[cnt + 1];
+
+ if (symidx == 0)
+ {
+ /* Nothing in here. No bit in the bitset should be set either. */
+ if (bitset != 0)
+ ERROR (gettext ("\
+section [%2d] '%s': hash chain for bucket %zu empty but bitset is not\n"),
+ idx, section_name (ebl, idx), cnt / 2 - 1);
+
+ continue;
+ }
+
+ if (symidx < symbias)
+ {
+ ERROR (gettext ("\
+section [%2d] '%s': hash chain for bucket %zu lower than symbol index bias\n"),
+ idx, section_name (ebl, idx), cnt / 2 - 1);
+ continue;
+ }
+
+ Elf32_Word collected_bitset = 0;
+ while (symidx - symbias < maxidx)
+ {
+ Elf32_Word chainhash = ((Elf32_Word *) data->d_buf)[2 + 2 * nbuckets
+ + symidx
+ - symbias];
+
+ if (symdata != NULL)
+ {
+ /* Check that the referenced symbol is not undefined. */
+ GElf_Sym sym_mem;
+ GElf_Sym *sym = gelf_getsym (symdata, symidx, &sym_mem);
+ if (sym != NULL && sym->st_shndx == SHN_UNDEF)
+ ERROR (gettext ("\
+section [%2d] '%s': symbol %u referenced in chain for bucket %zu is undefined\n"),
+ idx, section_name (ebl, idx), symidx, cnt / 2 - 1);
+
+ const char *symname = elf_strptr (ebl->elf, symshdr->sh_link,
+ sym->st_name);
+ if (symname != NULL)
+ {
+ Elf32_Word hval = elf_gnu_hash (symname);
+ if ((hval & ~1u) != (chainhash & ~1u))
+ ERROR (gettext ("\
+section [%2d] '%s': hash value for symbol %u in chain for bucket %zu wrong\n"),
+ idx, section_name (ebl, idx), symidx, cnt / 2 - 1);
+ }
+ }
+
+ collected_bitset |= 1 << ((chainhash >> 5) & 31);
+
+ if ((chainhash & 1) != 0)
+ break;
+
+ ++symidx;
+ }
+
+ if (symidx - symbias >= maxidx)
+ ERROR (gettext ("\
+section [%2d] '%s': hash chain for bucket %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt / 2 - 1);
+ else if (symshdr != NULL
+ && symidx > symshdr->sh_size / symshdr->sh_entsize)
+ ERROR (gettext ("\
+section [%2d] '%s': symbol reference in chain for bucket %zu out of bounds\n"),
+ idx, section_name (ebl, idx), cnt / 2 - 1);
+
+ if (bitset != collected_bitset)
+ ERROR (gettext ("\
+section [%2d] '%s': bitset for bucket %zu does not match chain entries: computed %#x, reported %#x\n"),
+ idx, section_name (ebl, idx), cnt / 2 - 1,
+ collected_bitset, bitset);
+ }
+}
+
+
+static void
+check_hash (int tag, Ebl *ebl, GElf_Ehdr *ehdr, GElf_Shdr *shdr, int idx)
{
if (ehdr->e_type == ET_REL)
{
@@ -1744,9 +2023,11 @@ section [%2d] '%s': relocatable files cannot have hash tables\n"),
section [%2d] '%s': hash table not for dynamic symbol table\n"),
idx, section_name (ebl, idx));
- if (shdr->sh_entsize != sizeof (Elf32_Word))
+ if (shdr->sh_entsize != (tag == SHT_GNU_HASH
+ ? sizeof (Elf32_Word)
+ : (size_t) ebl_sysvhash_entrysize (ebl)))
ERROR (gettext ("\
-section [%2d] '%s': entry size does not match Elf32_Word\n"),
+section [%2d] '%s': hash table entry size incorrect\n"),
idx, section_name (ebl, idx));
if ((shdr->sh_flags & SHF_ALLOC) == 0)
@@ -1756,40 +2037,26 @@ section [%2d] '%s': entry size does not match Elf32_Word\n"),
if (shdr->sh_size < 2 * shdr->sh_entsize)
{
ERROR (gettext ("\
-section [%2d] '%s': hash table has not even room for nbucket and nchain\n"),
+section [%2d] '%s': hash table has not even room for initial two administrative entries\n"),
idx, section_name (ebl, idx));
return;
}
- Elf32_Word nbucket = ((Elf32_Word *) data->d_buf)[0];
- Elf32_Word nchain = ((Elf32_Word *) data->d_buf)[1];
-
- if (shdr->sh_size < (2 + nbucket + nchain) * shdr->sh_entsize)
- ERROR (gettext ("\
-section [%2d] '%s': hash table section is too small (is %ld, expected %ld)\n"),
- idx, section_name (ebl, idx), (long int) shdr->sh_size,
- (long int) ((2 + nbucket + nchain) * shdr->sh_entsize));
-
- if (symshdr != NULL)
+ switch (tag)
{
- size_t symsize = symshdr->sh_size / symshdr->sh_entsize;
- size_t cnt;
-
- if (nchain < symshdr->sh_size / symshdr->sh_entsize)
- ERROR (gettext ("section [%2d] '%s': chain array not large enough\n"),
- idx, section_name (ebl, idx));
+ case SHT_HASH:
+ if (ebl_sysvhash_entrysize (ebl) == sizeof (Elf64_Xword))
+ check_sysv_hash64 (ebl, shdr, data, idx, symshdr);
+ else
+ check_sysv_hash (ebl, shdr, data, idx, symshdr);
+ break;
- for (cnt = 2; cnt < 2 + nbucket; ++cnt)
- if (((Elf32_Word *) data->d_buf)[cnt] >= symsize)
- ERROR (gettext ("\
-section [%2d] '%s': hash bucket reference %zu out of bounds\n"),
- idx, section_name (ebl, idx), cnt - 2);
+ case SHT_GNU_HASH:
+ check_gnu_hash (ebl, shdr, data, idx, symshdr);
+ break;
- for (; cnt < 2 + nbucket + nchain; ++cnt)
- if (((Elf32_Word *) data->d_buf)[cnt] >= symsize)
- ERROR (gettext ("\
-section [%2d] '%s': hash chain reference %zu out of bounds\n"),
- idx, section_name (ebl, idx), cnt - 2 - nbucket);
+ default:
+ assert (! "should not happen");
}
}
@@ -2178,7 +2445,7 @@ section [%2d] '%s': symbol %d: local symbol with version\n"),
index we need for this symbol. */
struct version_namelist *runp = version_namelist;
while (runp != NULL)
- if (runp->ndx == *versym)
+ if (runp->ndx == (*versym & 0x7fff))
break;
else
runp = runp->next;
@@ -2945,7 +3212,8 @@ section [%2zu] '%s': relocatable files cannot have dynamic symbol tables\n"),
break;
case SHT_HASH:
- check_hash (ebl, ehdr, shdr, cnt);
+ case SHT_GNU_HASH:
+ check_hash (shdr->sh_type, ebl, ehdr, shdr, cnt);
break;
case SHT_NULL: