On 2023/10/17 23:05, Fabiano Rosas wrote:
Alex Bennée <[email protected]> writes:
From: Akihiko Odaki <[email protected]>
An array is a more appropriate data structure than a list for gdb_regs
since it is initialized only with append operation and read-only after
initialization.
Signed-off-by: Akihiko Odaki <[email protected]>
Reviewed-by: Alistair Francis <[email protected]>
Message-Id: <[email protected]>
[AJB: fixed a checkpatch violation]
Signed-off-by: Alex Bennée <[email protected]>
Message-Id: <[email protected]>
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index 7b8347ed5a..3968369554 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -502,7 +502,7 @@ struct CPUState {
CPUJumpCache *tb_jmp_cache;
- struct GDBRegisterState *gdb_regs;
+ GArray *gdb_regs;
int gdb_num_regs;
int gdb_num_g_regs;
QTAILQ_ENTRY(CPUState) node;
diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c
index 62608a5389..b1532118d1 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -51,7 +51,6 @@ typedef struct GDBRegisterState {
gdb_get_reg_cb get_reg;
gdb_set_reg_cb set_reg;
const char *xml;
- struct GDBRegisterState *next;
} GDBRegisterState;
GDBState gdbserver_state;
@@ -386,7 +385,8 @@ static const char *get_feature_xml(const char *p, const
char **newp,
xml,
g_markup_printf_escaped("<xi:include href=\"%s\"/>",
cc->gdb_core_xml_file));
- for (r = cpu->gdb_regs; r; r = r->next) {
+ for (guint i = 0; i < cpu->gdb_regs->len; i++) {
It seems we can reach here before having initialized gdb_regs at
gdb_register_coprocessor():
Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault.
0x0000555555e5310b in get_feature_xml (p=0x555556a99118
<gdbserver_state+56> "target.xml:0,ffb", newp=0x7fffffffc6b0,
process=0x555557a21dd0) at ../gdbstub/gdbstub.c:388
(gdb) p/x cpu->gdb_regs
$1 = 0x0
Using:
qemu-system-x86 ... -s -s
just connect GDB and it crashes.
Hi,
Sorry for trouble and thank you for reporting.
I have just posted a fix "[PATCH v4 1/5] gdbstub: Check if gdb_regs is
NULL" as part of series "[PATCH v4 0/5] gdbstub and TCG plugin
improvements". Please test it if possible.
Alex, you may pick the patch early since the bug is quite a serious.
Please add "Reported-by: Fabiano Rosas <[email protected]>" when you do so
since I forgot it. You may skip applying target/riscv patches though
since the maintainers may still have something to comment.
Regards,
Akihiko Odaki
