On 03/12/2017 04:28 AM, Laurent Vivier wrote:
Le 11/03/2017 à 04:42, Richard Henderson a écrit :
Reading and writing to an sa_restorer member that isn't supposed to
exist corrupts user memory. Introduce TARGET_ARCH_HAS_SA_RESTORER,
similar to the kernel's __ARCH_HAS_SA_RESTORER.
Reported-by: Helge Deller <del...@gmx.de>
Signed-off-by: Richard Henderson <r...@twiddle.net>
---
linux-user/signal.c | 4 ++--
linux-user/syscall_defs.h | 13 +++++++++++++
2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/linux-user/signal.c b/linux-user/signal.c
index a67db04..c6b043b 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -777,7 +777,7 @@ int do_sigaction(int sig, const struct target_sigaction
*act,
if (oact) {
__put_user(k->_sa_handler, &oact->_sa_handler);
__put_user(k->sa_flags, &oact->sa_flags);
-#if !defined(TARGET_MIPS)
+#ifdef TARGET_ARCH_HAS_SA_RESTORER
__put_user(k->sa_restorer, &oact->sa_restorer);
#endif
/* Not swapped. */
@@ -787,7 +787,7 @@ int do_sigaction(int sig, const struct target_sigaction
*act,
/* FIXME: This is not threadsafe. */
__get_user(k->_sa_handler, &act->_sa_handler);
__get_user(k->sa_flags, &act->sa_flags);
-#if !defined(TARGET_MIPS)
+#ifdef TARGET_ARCH_HAS_SA_RESTORER
__get_user(k->sa_restorer, &act->sa_restorer);
#endif
/* To be swapped in target_to_host_sigset. */
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 40c5027..8b1ad74 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -445,6 +445,7 @@ int do_sigaction(int sig, const struct target_sigaction
*act,
#define TARGET_SA_RESTART 2u
#define TARGET_SA_NODEFER 0x20u
#define TARGET_SA_RESETHAND 4u
+#define TARGET_ARCH_HAS_SA_RESTORER 1
#elif defined(TARGET_MIPS)
#define TARGET_SA_NOCLDSTOP 0x00000001
#define TARGET_SA_NOCLDWAIT 0x00010000
@@ -483,6 +484,10 @@ int do_sigaction(int sig, const struct target_sigaction
*act,
#define TARGET_SA_RESTORER 0x04000000
#endif
+#ifdef TARGET_SA_RESTORER
+#define TARGET_ARCH_HAS_SA_RESTORER 1
+#endif
+
#if defined(TARGET_ALPHA)
#define TARGET_SIGHUP 1
@@ -718,19 +723,27 @@ struct target_sigaction {
abi_ulong _sa_handler;
#endif
target_sigset_t sa_mask;
+#ifdef TARGET_ARCH_HAS_SA_RESTORER
+ /* ??? This is always present, but ignored unless O32. */
If it is always present, why it is defined conditionally?
TARGET_ARCH_HAS_SA_RESTORER is defined only for O32.
I don't know. It's a kernel inconsistency.
TARGET_ALPHA has a sa_restorer field, but TARGET_ARCH_HAS_SA_RESTORER is
not defined.
TARGET_ALPHA has KA_RESTORER, not sa_restorer. The restorer value is passed to
sigaction in a 5th register argument. Less than handy that qemu doesn't
distinguish the two structs...
r~
