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| author | Alan Modra <amodra@gmail.com> | 2017-09-27 15:14:00 +0930 |
|---|---|---|
| committer | Alan Modra <amodra@gmail.com> | 2017-09-27 15:54:18 +0930 |
| commit | 6bd6a03d6975a96802b37741a99644570e52a72b (patch) | |
| tree | 50db676ae71b1bf684cba370532f78869455d0bf /binutils | |
| parent | cd28e7aaf35f7de5033ecd619b56064136bb190b (diff) | |
| download | gdb-6bd6a03d6975a96802b37741a99644570e52a72b.zip gdb-6bd6a03d6975a96802b37741a99644570e52a72b.tar.gz gdb-6bd6a03d6975a96802b37741a99644570e52a72b.tar.bz2 | |
PR22216, infinite loop in readelf process_symbol_table
This should make readelf bombproof given a fuzzed DT_HASH. Also
removes a bogus check that would have resulted in wrong histograms.
PR 22216
* readelf.c (process_symbol_table): Check that DT_HASH symbol
chains are only visited once, and report an error if not. Display
invalid symbol index if chain is out of range. Use the same logic
when calculating histograms rather than the PR 17531 fix. Delete
bogus check that chained index is less than number of buckets.
Diffstat (limited to 'binutils')
| -rw-r--r-- | binutils/ChangeLog | 9 | ||||
| -rw-r--r-- | binutils/readelf.c | 43 |
2 files changed, 34 insertions, 18 deletions
diff --git a/binutils/ChangeLog b/binutils/ChangeLog index dc4faf5..a4de14c 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,12 @@ +2017-09-27 Alan Modra <amodra@gmail.com> + + PR 22216 + * readelf.c (process_symbol_table): Check that DT_HASH symbol + chains are only visited once, and report an error if not. Display + invalid symbol index if chain is out of range. Use the same logic + when calculating histograms rather than the PR 17531 fix. Delete + bogus check that chained index is less than number of buckets. + 2017-09-26 Nick Clifton <nickc@redhat.com> PR 22154 diff --git a/binutils/readelf.c b/binutils/readelf.c index 3e5ad0e..260aedf 100644 --- a/binutils/readelf.c +++ b/binutils/readelf.c @@ -11436,6 +11436,7 @@ process_symbol_table (FILE * file) if (dynamic_info[DT_HASH]) { bfd_vma si; + char *visited; printf (_("\nSymbol table for image:\n")); if (is_32bit_elf) @@ -11443,14 +11444,22 @@ process_symbol_table (FILE * file) else printf (_(" Num Buc: Value Size Type Bind Vis Ndx Name\n")); + visited = xcmalloc (nchains, 1); + memset (visited, 0, nchains); for (hn = 0; hn < nbuckets; hn++) { - if (! buckets[hn]) - continue; - - for (si = buckets[hn]; si < nchains && si > 0; si = chains[si]) - print_dynamic_symbol (si, hn); + for (si = buckets[hn]; si > 0; si = chains[si]) + { + print_dynamic_symbol (si, hn); + if (si >= nchains || visited[si]) + { + error (_("histogram chain is corrupt\n")); + break; + } + visited[si] = 1; + } } + free (visited); } if (dynamic_info_DT_GNU_HASH) @@ -11609,7 +11618,7 @@ process_symbol_table (FILE * file) unsigned long maxlength = 0; unsigned long nzero_counts = 0; unsigned long nsyms = 0; - unsigned long chained; + char *visited; printf (_("\nHistogram for bucket list length (total of %lu buckets):\n"), (unsigned long) nbuckets); @@ -11620,28 +11629,26 @@ process_symbol_table (FILE * file) error (_("Out of memory allocating space for histogram buckets\n")); return FALSE; } + visited = xcmalloc (nchains, 1); + memset (visited, 0, nchains); printf (_(" Length Number %% of total Coverage\n")); for (hn = 0; hn < nbuckets; ++hn) { - for (si = buckets[hn], chained = 0; - si > 0 && si < nchains && si < nbuckets && chained <= nchains; - si = chains[si], ++chained) + for (si = buckets[hn]; si > 0; si = chains[si]) { ++nsyms; if (maxlength < ++lengths[hn]) ++maxlength; + if (si >= nchains || visited[si]) + { + error (_("histogram chain is corrupt\n")); + break; + } + visited[si] = 1; } - - /* PR binutils/17531: A corrupt binary could contain broken - histogram data. Do not go into an infinite loop trying - to process it. */ - if (chained > nchains) - { - error (_("histogram chain is corrupt\n")); - break; - } } + free (visited); counts = (unsigned long *) calloc (maxlength + 1, sizeof (*counts)); if (counts == NULL) |