On Wed, 28 Feb 2024 at 12:00, Alex Bennée <alex.ben...@linaro.org> wrote:
>
> With the new plugin register API we can now track changes to register
> values. Currently the implementation is fairly dumb which will slow
> down if a large number of register values are being tracked. This
> could be improved by only instrumenting instructions which mention
> registers we are interested in tracking.
>
Hi; Coverity complains about a possible NULL dereference
in this code (CID 1534929):
> @@ -153,8 +224,39 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struct
> qemu_plugin_tb *tb)
> }
> }
>
> + /*
> + * Check the disassembly to see if a register we care about
> + * will be affected by this instruction. This relies on the
> + * dissembler doing something sensible for the registers we
> + * care about.
> + */
> + if (disas_assist && rmatches) {
> + check_regs_next = false;
> + gchar *args = g_strstr_len(insn_disas, -1, " ");
g_strstr_len() can return NULL if it doesn't find the
string being searched for...
> + for (int n = 0; n < all_reg_names->len; n++) {
> + gchar *reg = g_ptr_array_index(all_reg_names, n);
> + if (g_strrstr(args, reg)) {
...but it's not valid to pass NULL as the argument to
g_strrstr().
> + check_regs_next = true;
> + skip = false;
> + }
> + }
> + }
thanks
-- PMM
