Ziyang Zhang <[email protected]> writes:
Register a syscall filter callback in tests/tcg/plugins/sycall.c,
returns a specific value for a magic system call number, and check
it in tests/tcg/multiarch/test-plugin-syscall-filter.c.
Signed-off-by: Ziyang Zhang <[email protected]>
Co-authored-by: Mingyuan Xia <[email protected]>
---
tests/tcg/multiarch/Makefile.target | 4 +++-
.../multiarch/test-plugin-syscall-filter.c | 20 +++++++++++++++++++
tests/tcg/plugins/syscall.c | 15 ++++++++++++++
3 files changed, 38 insertions(+), 1 deletion(-)
create mode 100644 tests/tcg/multiarch/test-plugin-syscall-filter.c
diff --git a/tests/tcg/multiarch/Makefile.target
b/tests/tcg/multiarch/Makefile.target
index f5b4d2b813..4005e3a8a9 100644
--- a/tests/tcg/multiarch/Makefile.target
+++ b/tests/tcg/multiarch/Makefile.target
@@ -202,8 +202,10 @@ run-plugin-test-plugin-mem-access-with-libmem.so: \
CHECK_PLUGIN_OUTPUT_COMMAND= \
$(SRC_PATH)/tests/tcg/multiarch/check-plugin-output.sh \
$(QEMU) $<
+run-plugin-test-plugin-syscall-filter-with-libsyscall.so:
-EXTRA_RUNS_WITH_PLUGIN += run-plugin-test-plugin-mem-access-with-libmem.so
+EXTRA_RUNS_WITH_PLUGIN += run-plugin-test-plugin-mem-access-with-libmem.so \
+
run-plugin-test-plugin-syscall-filter-with-libsyscall.so
endif
# Update TESTS
diff --git a/tests/tcg/multiarch/test-plugin-syscall-filter.c
b/tests/tcg/multiarch/test-plugin-syscall-filter.c
new file mode 100644
index 0000000000..cc694e0a71
--- /dev/null
+++ b/tests/tcg/multiarch/test-plugin-syscall-filter.c
@@ -0,0 +1,20 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This test attempts to execute a magic syscall. The syscall test plugin
+ * should intercept this and returns an expected value.
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+ long ret = syscall(0x66CCFF);
+ if (ret != 0xFFCC66) {
+ perror("ERROR: syscall returned unexpected value!!!");
+ return EXIT_FAILURE;
+ }
+ return EXIT_SUCCESS;
+}
This breaks some arches:
(gdb) r
Starting program: /home/alex/lsrc/qemu.git/builds/sanitisers/qemu-arm
-plugin tests/tcg/plugins/libsyscall.so -d plugin
./tests/tcg/arm-linux-user/test-plugin-syscall-filter
[New Thread 0x7ffff37ff6c0 (LWP 63692)]
qemu: uncaught target signal 4 (Illegal instruction) - core dumped
syscall no. calls errors
45 5 0
338 1 1
256 1 0
191 1 0
398 1 1
125 1 0
384 1 0
332 1 0
Thread 1 "qemu-arm" received signal SIGILL, Illegal instruction.
Download failed: Invalid argument. Continuing without source file
./nptl/../sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S.
__syscall_cancel_arch () at
../sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S:56
warning: 56 ../sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S: No such
file or directory
(gdb) bt
#0 __syscall_cancel_arch () at
../sysdeps/unix/sysv/linux/x86_64/syscall_cancel.S:56
#1 0x00007ffff6a51668 in __internal_syscall_cancel (a1=<optimized out>,
a2=a2@entry=8, a3=a3@entry=0, a4=a4@entry=0, a5=a5@entry=0, a6=a6@entry=0, nr=130)
at ./nptl/cancellation.c:49
#2 0x00007ffff6a516ad in __syscall_cancel (a1=<optimized out>,
a2=a2@entry=8, a3=a3@entry=0, a4=a4@entry=0, a5=a5@entry=0, a6=a6@entry=0, nr=130)
at ./nptl/cancellation.c:75
#3 0x00007ffff6a0207d in __GI___sigsuspend (set=<optimized out>) at
../sysdeps/unix/sysv/linux/sigsuspend.c:26
#4 0x0000555555a49b80 in die_with_signal (host_sig=4) at
../../linux-user/signal.c:807
#5 0x0000555555a49ed0 in dump_core_and_abort (env=0x532000004300,
target_sig=4) at ../../linux-user/signal.c:847
#6 0x0000555555a4c969 in handle_pending_signal (cpu_env=0x532000004300,
sig=4, k=0x5250000029d0) at ../../linux-user/signal.c:1306
#7 0x0000555555a4d0e5 in process_pending_signals (cpu_env=0x532000004300)
at ../../linux-user/signal.c:1386
#8 0x0000555555873930 in cpu_loop (env=0x532000004300) at
../../linux-user/arm/cpu_loop.c:479
#9 0x0000555555a3eca7 in main (argc=6, argv=0x7fffffffe588,
envp=0x7fffffffe5c0) at ../../linux-user/main.c:1035
(gdb)
\ No newline at end of file
diff --git a/tests/tcg/plugins/syscall.c b/tests/tcg/plugins/syscall.c
index 42801f5c86..1323e18bc0 100644
--- a/tests/tcg/plugins/syscall.c
+++ b/tests/tcg/plugins/syscall.c
@@ -170,6 +170,20 @@ static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned
int vcpu_idx,
}
}
+static bool vcpu_syscall_filter(qemu_plugin_id_t id, unsigned int vcpu_index,
+ int64_t num, uint64_t a1, uint64_t a2,
+ uint64_t a3, uint64_t a4, uint64_t a5,
+ uint64_t a6, uint64_t a7, uint64_t a8,
+ uint64_t *ret)
+{
+ if (num == 0x66CCFF) {
+ *ret = 0xFFCC66;
+ qemu_plugin_outs("syscall 0x66CCFF filtered, ret=0xFFCC66\n");
+ return true;
+ }
+ return false;
+}
+
static void print_entry(gpointer val, gpointer user_data)
{
SyscallStats *entry = (SyscallStats *) val;
@@ -255,6 +269,7 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t
id,
qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall);
qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret);
+ qemu_plugin_register_vcpu_syscall_filter_cb(id, vcpu_syscall_filter);
qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
return 0;
}
