commit 0a545e "elflint: Add various low-level checks." introduced a bug
in the handling of the gnu_symbias. The symbol in the bucket should first
be compared to STN_UNDEF before applying the bias. And the used symbol
index should have the bias added when compared against plain hash symbol.
Found on Debian wheezy with run-elflint-self.sh.
Signed-off-by: Mark Wielaard <mjw(a)redhat.com>
---
src/ChangeLog | 4 ++++
src/elflint.c | 30 ++++++++++++++++--------------
2 files changed, 20 insertions(+), 14 deletions(-)
diff --git a/src/ChangeLog b/src/ChangeLog
index dad984e..bb9580a 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2015-03-09 Mark Wielaard <mjw(a)redhat.com>
+
+ * elflint.c (compare_hash_gnu_hash): Correct gnu_symbias usage.
+
2015-01-03 Mark Wielaard <mjw(a)redhat.com>
* elfcmp (main): Check section name is not NULL. Check sh_entsize
diff --git a/src/elflint.c b/src/elflint.c
index 143424c..a6f9b68 100644
--- a/src/elflint.c
+++ b/src/elflint.c
@@ -2397,20 +2397,22 @@ hash section [%2zu] '%s' uses too much data\n"),
for (Elf32_Word cnt = 0; cnt < gnu_nbucket; ++cnt)
{
- Elf32_Word symidx = gnu_bucket[cnt] - gnu_symbias;;
- if (symidx != STN_UNDEF)
- do
- {
- if (symidx >= max_nsyms || symidx >= nentries)
- {
- ERROR (gettext ("\
-hash section [%2zu] '%s' invalid symbol index\n"),
- gnu_hash_idx, gnu_hash_name);
- return;
- }
- used[symidx] |= 1;
- }
- while ((gnu_chain[symidx++] & 1u) == 0);
+ if (gnu_bucket[cnt] != STN_UNDEF)
+ {
+ Elf32_Word symidx = gnu_bucket[cnt] - gnu_symbias;
+ do
+ {
+ if (symidx >= max_nsyms || symidx + gnu_symbias >= nentries)
+ {
+ ERROR (gettext ("\
+hash section [%2zu] '%s' invalid symbol index %" PRIu32 " (max_nsyms:
%" PRIu32 ", nentries: %" PRIu32 "\n"),
+ gnu_hash_idx, gnu_hash_name, symidx, max_nsyms, nentries);
+ return;
+ }
+ used[symidx + gnu_symbias] |= 1;
+ }
+ while ((gnu_chain[symidx++] & 1u) == 0);
+ }
}
/* Now go over the old hash table and check that we cover the same
--
1.8.3.1
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On Mon, 2015-03-09 at 16:45 +0100, Mark Wielaard wrote:
commit 0a545e "elflint: Add various low-level checks."
introduced a bug
in the handling of the gnu_symbias. The symbol in the bucket should first
be compared to STN_UNDEF before applying the bias. And the used symbol
index should have the bias added when compared against plain hash symbol.
Found on Debian wheezy with run-elflint-self.sh.
I pushed this to master.