[Qemu-devel] [PATCH] linux-user: Correct a few missuses of host addresses

["Edgar E. Iglesias" <edgar.iglesias@gmail.com>]

Hi,

I ran into a couple of missuses of where signal setup was directly passing
host pointers to the guest.

I've run tested the CRIS and MicroBlaze changes. The S390 and SH4 are only
compile tested.

Cheers

commit f47829920bc06abddfd7d55cec97ec798f4668e2
Author: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Date:   Mon Aug 22 18:44:58 2011 +0200

    linux-user: Correct a few missuses of host addresses
    
    Fix a few cases where we were passing host pointers to the
    guest.
    
    Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 07ad07a..89276eb 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -3064,10 +3064,10 @@ static void setup_frame(int sig, struct target_sigaction *ka,
         goto give_sigsegv;
 
     /* Set up registers for signal handler */
-    regs->gregs[15] = (unsigned long) frame;
+    regs->gregs[15] = frame_addr;
     regs->gregs[4] = signal; /* Arg for signal handler */
     regs->gregs[5] = 0;
-    regs->gregs[6] = (unsigned long) &frame->sc;
+    regs->gregs[6] = frame_addr += offsetof(typeof(*frame), sc);
     regs->pc = (unsigned long) ka->_sa_handler;
 
     unlock_user_struct(frame, frame_addr, 1);
@@ -3127,10 +3127,10 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka,
         goto give_sigsegv;
 
     /* Set up registers for signal handler */
-    regs->gregs[15] = (unsigned long) frame;
+    regs->gregs[15] = frame_addr;
     regs->gregs[4] = signal; /* Arg for signal handler */
-    regs->gregs[5] = (unsigned long) &frame->info;
-    regs->gregs[6] = (unsigned long) &frame->uc;
+    regs->gregs[5] = frame_addr + offsetof(typeof(*frame), info);
+    regs->gregs[6] = frame_addr + offsetof(typeof(*frame), uc);
     regs->pc = (unsigned long) ka->_sa_handler;
 
     unlock_user_struct(frame, frame_addr, 1);
@@ -3381,11 +3381,12 @@ static void setup_frame(int sig, struct target_sigaction *ka,
         goto badframe;
 
     /* Set up registers for signal handler */
-    env->regs[1] = (unsigned long) frame;
+    env->regs[1] = frame_addr;
     /* Signal handler args: */
     env->regs[5] = sig; /* Arg 0: signum */
     env->regs[6] = 0;
-    env->regs[7] = (unsigned long) &frame->uc; /* arg 1: sigcontext */
+    /* arg 1: sigcontext */
+    env->regs[7] = frame_addr += offsetof(typeof(*frame), uc);
 
     /* Offset of 4 to handle microblaze rtid r14, 0 */
     env->sregs[SR_PC] = (unsigned long)ka->_sa_handler;
@@ -3559,11 +3560,11 @@ static void setup_frame(int sig, struct target_sigaction *ka,
 	setup_sigcontext(&frame->sc, env);
 
 	/* Move the stack and setup the arguments for the handler.  */
-	env->regs[R_SP] = (uint32_t) (unsigned long) frame;
+	env->regs[R_SP] = frame_addr;
 	env->regs[10] = sig;
 	env->pc = (unsigned long) ka->_sa_handler;
 	/* Link SRP so the guest returns through the trampoline.  */
-	env->pregs[PR_SRP] = (uint32_t) (unsigned long) &frame->retcode[0];
+	env->pregs[PR_SRP] = frame_addr + offsetof(typeof(*frame), retcode);
 
 	unlock_user_struct(frame, frame_addr, 1);
 	return;
@@ -3769,11 +3770,11 @@ static void setup_frame(int sig, struct target_sigaction *ka,
     }
 
     /* Set up registers for signal handler */
-    env->regs[15] = (target_ulong)(unsigned long) frame;
+    env->regs[15] = frame_addr;
     env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;
 
     env->regs[2] = sig; //map_signal(sig);
-    env->regs[3] = (target_ulong)(unsigned long) &frame->sc;
+    env->regs[3] = frame_addr += offsetof(typeof(*frame), sc);
 
     /* We forgot to include these in the sigcontext.
        To avoid breaking binary compatibility, they are passed as args. */
@@ -3844,12 +3845,12 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka,
     }
 
     /* Set up registers for signal handler */
-    env->regs[15] = (target_ulong)(unsigned long) frame;
+    env->regs[15] = frame_addr;
     env->psw.addr = (target_ulong) ka->_sa_handler | PSW_ADDR_AMODE;
 
     env->regs[2] = sig; //map_signal(sig);
-    env->regs[3] = (target_ulong)(unsigned long) &frame->info;
-    env->regs[4] = (target_ulong)(unsigned long) &frame->uc;
+    env->regs[3] = frame_addr + offsetof(typeof(*frame), info);
+    env->regs[4] = frame_addr + offsetof(typeof(*frame), uc);
     return;
 
 give_sigsegv: