The function check_access() verify that memory accesses are not
done out of their bounds. This is good.
However, this function is called at each run of simplify_loads()
which means that the same warning can be given multiple times
which is annoying.
Fix this by using the newly added 'tainted' field to not warn
a second time on this instruction.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
flow.c | 6 +++++-
validation/check_access-multi.c | 15 +++++++++++++++
2 files changed, 20 insertions(+), 1 deletion(-)
create mode 100644 validation/check_access-multi.c
diff --git a/flow.c b/flow.c
index b6412461b..b28d2e408 100644
--- a/flow.c
+++ b/flow.c
@@ -646,11 +646,15 @@ void check_access(struct instruction *insn)
int offset = insn->offset, bit = bytes_to_bits(offset) + insn->size;
struct symbol *sym = pseudo->sym;
- if (sym->bit_size > 0 && (offset < 0 || bit > sym->bit_size))
+ if (sym->bit_size > 0 && (offset < 0 || bit > sym->bit_size)) {
+ if (insn->tainted)
+ return;
warning(insn->pos, "invalid access %s '%s' (%d %d)",
offset < 0 ? "below" : "past the end of",
show_ident(sym->ident), offset,
bits_to_bytes(sym->bit_size));
+ insn->tainted = 1;
+ }
}
}
diff --git a/validation/check_access-multi.c b/validation/check_access-multi.c
new file mode 100644
index 000000000..5d6c6ce30
--- /dev/null
+++ b/validation/check_access-multi.c
@@ -0,0 +1,15 @@
+extern long *a;
+extern long b[1];
+
+static void foo(void)
+{
+ *a = b[1];
+}
+
+/*
+ * check-name: check_access-multi
+ *
+ * check-error-start
+check_access-multi.c:6:15: warning: invalid access past the end of 'b' (8 8)
+ * check-error-end
+ */
--
2.16.2
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