From: Alan Modra <amodra@gmail.com>
To: binutils@sourceware.org
Subject: asan: segfault in coff_mangle_symbols
Date: Mon, 24 Apr 2023 21:02:50 +0930 [thread overview]
Message-ID: <ZEZo4oH/oT6Gu/5S@squeak.grove.modra.org> (raw)
The testcase managed to trigger creation of a wild pointer in
coff_slurp_symbol_table. Stop that happening, and fix an unrelated
problem I happened to see in bfd_coff_get_syment.
* coff-bfd.c (bfd_coff_get_syment): Clear fix_value after
converting n_value from a pointer to an index.
* coffcode.h (coff_slurp_symbol_table <C_BSTAT>): Sanity check
symbol value before converting to a pointer.
diff --git a/bfd/coff-bfd.c b/bfd/coff-bfd.c
index 292778ecb56..9aceeb080a7 100644
--- a/bfd/coff-bfd.c
+++ b/bfd/coff-bfd.c
@@ -45,9 +45,12 @@ bfd_coff_get_syment (bfd *abfd,
*psyment = csym->native->u.syment;
if (csym->native->fix_value)
- psyment->n_value =
- ((psyment->n_value - (uintptr_t) obj_raw_syments (abfd))
- / sizeof (combined_entry_type));
+ {
+ psyment->n_value =
+ ((psyment->n_value - (uintptr_t) obj_raw_syments (abfd))
+ / sizeof (combined_entry_type));
+ csym->native->fix_value = 0;
+ }
/* FIXME: We should handle fix_line here. */
diff --git a/bfd/coffcode.h b/bfd/coffcode.h
index 423f6c070ef..594f3e0457b 100644
--- a/bfd/coffcode.h
+++ b/bfd/coffcode.h
@@ -4852,13 +4852,18 @@ coff_slurp_symbol_table (bfd * abfd)
case C_BSTAT:
dst->symbol.flags = BSF_DEBUGGING;
- /* The value is actually a symbol index. Save a pointer
- to the symbol instead of the index. FIXME: This
- should use a union. */
- src->u.syment.n_value
- = (uintptr_t) (native_symbols + src->u.syment.n_value);
- dst->symbol.value = src->u.syment.n_value;
- src->fix_value = 1;
+ if (src->u.syment.n_value >= obj_raw_syment_count (abfd))
+ dst->symbol.value = 0;
+ else
+ {
+ /* The value is actually a symbol index. Save a pointer
+ to the symbol instead of the index. FIXME: This
+ should use a union. */
+ src->u.syment.n_value
+ = (uintptr_t) (native_symbols + src->u.syment.n_value);
+ dst->symbol.value = src->u.syment.n_value;
+ src->fix_value = 1;
+ }
break;
#endif
--
Alan Modra
Australia Development Lab, IBM
reply other threads:[~2023-04-24 11:32 UTC|newest]
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