The beginning of the structure, with pretaddr, should be just below
16-byte alignment. Disconnect fpstate from sigframe, just like the
kernel does.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/i386/signal.c | 104 +++++++++++++++++--------------
tests/tcg/x86_64/sigstack.c | 33 ++++++++++
tests/tcg/x86_64/Makefile.target | 1 +
3 files changed, 90 insertions(+), 48 deletions(-)
create mode 100644 tests/tcg/x86_64/sigstack.c
diff --git a/linux-user/i386/signal.c b/linux-user/i386/signal.c
index 60fa07d6f9..c49467de78 100644
--- a/linux-user/i386/signal.c
+++ b/linux-user/i386/signal.c
@@ -191,16 +191,7 @@ struct sigframe {
struct target_fpstate fpstate_unused;
abi_ulong extramask[TARGET_NSIG_WORDS-1];
char retcode[8];
-
- /*
- * This field will be 16-byte aligned in memory. Applying QEMU_ALIGNED
- * to it ensures that the base of the frame has an appropriate alignment
- * too.
- */
- struct target_fpstate fpstate QEMU_ALIGNED(8);
};
-#define TARGET_SIGFRAME_FXSAVE_OFFSET ( \
- offsetof(struct sigframe, fpstate) + TARGET_FPSTATE_FXSAVE_OFFSET)
struct rt_sigframe {
abi_ulong pretcode;
@@ -210,27 +201,21 @@ struct rt_sigframe {
struct target_siginfo info;
struct target_ucontext uc;
char retcode[8];
- struct target_fpstate fpstate QEMU_ALIGNED(8);
};
-#define TARGET_RT_SIGFRAME_FXSAVE_OFFSET ( \
- offsetof(struct rt_sigframe, fpstate) + TARGET_FPSTATE_FXSAVE_OFFSET)
#else
-
struct rt_sigframe {
abi_ulong pretcode;
struct target_ucontext uc;
struct target_siginfo info;
- struct target_fpstate fpstate QEMU_ALIGNED(16);
};
-#define TARGET_RT_SIGFRAME_FXSAVE_OFFSET ( \
- offsetof(struct rt_sigframe, fpstate) + TARGET_FPSTATE_FXSAVE_OFFSET)
#endif
/*
* Set up a signal frame.
*/
-static void xsave_sigcontext(CPUX86State *env, struct target_fpstate_fxsave
*fxsave,
+static void xsave_sigcontext(CPUX86State *env,
+ struct target_fpstate_fxsave *fxsave,
abi_ulong fxsave_addr)
{
if (!(env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE)) {
@@ -266,8 +251,9 @@ static void xsave_sigcontext(CPUX86State *env, struct
target_fpstate_fxsave *fxs
}
static void setup_sigcontext(struct target_sigcontext *sc,
- struct target_fpstate *fpstate, CPUX86State *env, abi_ulong mask,
- abi_ulong fpstate_addr)
+ struct target_fpstate *fpstate,
+ CPUX86State *env, abi_ulong mask,
+ abi_ulong fpstate_addr)
{
CPUState *cs = env_cpu(env);
#ifndef TARGET_X86_64
@@ -347,10 +333,11 @@ static void setup_sigcontext(struct target_sigcontext *sc,
* Determine which stack to use..
*/
-static inline abi_ulong
-get_sigframe(struct target_sigaction *ka, CPUX86State *env, size_t
fxsave_offset)
+static abi_ulong get_sigframe(struct target_sigaction *ka, CPUX86State *env,
+ size_t *frame_size, abi_ulong *fpsave_addr)
{
- unsigned long esp;
+ abi_ulong esp, orig;
+ size_t fpsave_size;
/* Default to using normal stack */
esp = get_sp_from_cpustate(env);
@@ -371,16 +358,23 @@ get_sigframe(struct target_sigaction *ka, CPUX86State
*env, size_t fxsave_offset
}
#endif
}
+ orig = esp;
- if (!(env->features[FEAT_1_EDX] & CPUID_FXSR)) {
- return (esp - (fxsave_offset + TARGET_FXSAVE_SIZE)) & -8ul;
- } else if (!(env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE)) {
- return ((esp - TARGET_FXSAVE_SIZE) & -16ul) - fxsave_offset;
+ if (!(env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE)) {
+ fpsave_size = TARGET_FXSAVE_SIZE;
+ esp = ROUND_DOWN(esp - fpsave_size, 16);
} else {
- size_t xstate_size =
- xsave_area_size(env->xcr0, false) +
TARGET_FP_XSTATE_MAGIC2_SIZE;
- return ((esp - xstate_size) & -64ul) - fxsave_offset;
+ fpsave_size = xsave_area_size(env->xcr0, false)
+ + TARGET_FP_XSTATE_MAGIC2_SIZE;
+ esp = ROUND_DOWN(esp - fpsave_size, 64);
}
+ *fpsave_addr = esp;
+
+ esp = esp - *frame_size + sizeof(abi_ulong);
+ esp = ROUND_DOWN(esp, 16) - sizeof(abi_ulong);
+
+ *frame_size = orig - esp;
+ return esp;
}
#ifndef TARGET_X86_64
@@ -405,26 +399,34 @@ void setup_frame(int sig, struct target_sigaction *ka,
target_sigset_t *set, CPUX86State *env)
{
abi_ulong frame_addr;
+ abi_ulong fpstate_addr;
+ size_t frame_size;
struct sigframe *frame;
+ struct target_fpstate *fpstate;
int i;
- frame_addr = get_sigframe(ka, env, TARGET_SIGFRAME_FXSAVE_OFFSET);
+ frame_size = sizeof(struct sigframe);
+ frame_addr = get_sigframe(ka, env, &frame_size, &fpstate_addr);
trace_user_setup_frame(env, frame_addr);
- if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+ frame = lock_user(VERIFY_WRITE, frame_addr, frame_size, false);
+ if (!frame) {
goto give_sigsegv;
+ }
+ fpstate = (void *)frame + (fpstate_addr - frame_addr);
__put_user(sig, &frame->sig);
- setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0],
- frame_addr + offsetof(struct sigframe, fpstate));
+ setup_sigcontext(&frame->sc, fpstate, env, set->sig[0], fpstate_addr);
- for(i = 1; i < TARGET_NSIG_WORDS; i++) {
+ for (i = 1; i < TARGET_NSIG_WORDS; i++) {
__put_user(set->sig[i], &frame->extramask[i - 1]);
}
- /* Set up to return from userspace. If provided, use a stub
- already in userspace. */
+ /*
+ * Set up to return from userspace.
+ * If provided, use a stub already in userspace.
+ */
if (ka->sa_flags & TARGET_SA_RESTORER) {
__put_user(ka->sa_restorer, &frame->pretcode);
} else {
@@ -443,11 +445,10 @@ void setup_frame(int sig, struct target_sigaction *ka,
cpu_x86_load_seg(env, R_CS, __USER_CS);
env->eflags &= ~TF_MASK;
- unlock_user_struct(frame, frame_addr, 1);
-
+ unlock_user(frame, frame_addr, frame_size);
return;
-give_sigsegv:
+ give_sigsegv:
force_sigsegv(sig);
}
#endif
@@ -458,17 +459,24 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
target_sigset_t *set, CPUX86State *env)
{
abi_ulong frame_addr;
+ abi_ulong fpstate_addr;
+ size_t frame_size;
#ifndef TARGET_X86_64
abi_ulong addr;
#endif
struct rt_sigframe *frame;
+ struct target_fpstate *fpstate;
int i;
- frame_addr = get_sigframe(ka, env, TARGET_RT_SIGFRAME_FXSAVE_OFFSET);
+ frame_size = sizeof(struct rt_sigframe);
+ frame_addr = get_sigframe(ka, env, &frame_size, &fpstate_addr);
trace_user_setup_rt_frame(env, frame_addr);
- if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+ frame = lock_user(VERIFY_WRITE, frame_addr, frame_size, false);
+ if (!frame) {
goto give_sigsegv;
+ }
+ fpstate = (void *)frame + (fpstate_addr - frame_addr);
/* These fields are only in rt_sigframe on 32 bit */
#ifndef TARGET_X86_64
@@ -490,10 +498,10 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
}
__put_user(0, &frame->uc.tuc_link);
target_save_altstack(&frame->uc.tuc_stack, env);
- setup_sigcontext(&frame->uc.tuc_mcontext, &frame->fpstate, env,
- set->sig[0], frame_addr + offsetof(struct rt_sigframe, fpstate));
+ setup_sigcontext(&frame->uc.tuc_mcontext, fpstate, env,
+ set->sig[0], fpstate_addr);
- for(i = 0; i < TARGET_NSIG_WORDS; i++) {
+ for (i = 0; i < TARGET_NSIG_WORDS; i++) {
__put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
}
@@ -533,15 +541,15 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
cpu_x86_load_seg(env, R_SS, __USER_DS);
env->eflags &= ~TF_MASK;
- unlock_user_struct(frame, frame_addr, 1);
-
+ unlock_user(frame, frame_addr, frame_size);
return;
-give_sigsegv:
+ give_sigsegv:
force_sigsegv(sig);
}
-static int xrstor_sigcontext(CPUX86State *env, struct target_fpstate_fxsave
*fxsave,
+static int xrstor_sigcontext(CPUX86State *env,
+ struct target_fpstate_fxsave *fxsave,
abi_ulong fxsave_addr)
{
if (env->features[FEAT_1_ECX] & CPUID_EXT_XSAVE) {
diff --git a/tests/tcg/x86_64/sigstack.c b/tests/tcg/x86_64/sigstack.c
new file mode 100644
index 0000000000..06cb847569
--- /dev/null
+++ b/tests/tcg/x86_64/sigstack.c
@@ -0,0 +1,33 @@
+#include <stdlib.h>
+#include <assert.h>
+#include <signal.h>
+#include <stdint.h>
+
+void __attribute__((noinline)) bar(void)
+{
+ exit(EXIT_SUCCESS);
+}
+
+void __attribute__((noinline, ms_abi)) foo(void)
+{
+ /*
+ * With ms_abi, there are call-saved xmm registers, which are forced
+ * to the stack around the call to sysv_abi bar(). If the signal
+ * stack frame is not properly aligned, movaps will raise #GP.
+ */
+ bar();
+}
+
+void sighandler(int num)
+{
+ void* sp = __builtin_dwarf_cfa();
+ assert((uintptr_t)sp % 16 == 0);
+ foo();
+}
+
+int main(void)
+{
+ signal(SIGUSR1, sighandler);
+ raise(SIGUSR1);
+ abort();
+}
diff --git a/tests/tcg/x86_64/Makefile.target b/tests/tcg/x86_64/Makefile.target
index e64aab1b81..d961599f64 100644
--- a/tests/tcg/x86_64/Makefile.target
+++ b/tests/tcg/x86_64/Makefile.target
@@ -13,6 +13,7 @@ X86_64_TESTS += vsyscall
X86_64_TESTS += noexec
X86_64_TESTS += cmpxchg
X86_64_TESTS += adox
+X86_64_TESTS += sigstack
TESTS=$(MULTIARCH_TESTS) $(X86_64_TESTS) test-x86_64
else
TESTS=$(MULTIARCH_TESTS)
--
2.34.1
