Merge branch 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / arch / arm / kernel / signal.c

diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 3a48b54c6405acf67042574856de4e3a655c5cd4..e2de50bf87425e4a55baa66ef68d1fe99e53e1f8 100644 (file)
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -41,8 +41,10 @@ static int preserve_crunch_context(struct crunch_sigframe __user *frame)
        return __copy_to_user(frame, kframe, sizeof(*frame));
 }
 
-static int restore_crunch_context(struct crunch_sigframe __user *frame)
+static int restore_crunch_context(char __user **auxp)
 {
+       struct crunch_sigframe __user *frame =
+               (struct crunch_sigframe __user *)*auxp;
        char kbuf[sizeof(*frame) + 8];
        struct crunch_sigframe *kframe;
 
@@ -53,6 +55,7 @@ static int restore_crunch_context(struct crunch_sigframe __user *frame)
        if (kframe->magic != CRUNCH_MAGIC ||
            kframe->size != CRUNCH_STORAGE_SIZE)
                return -1;
+       *auxp += CRUNCH_STORAGE_SIZE;
        crunch_task_restore(current_thread_info(), &kframe->storage);
        return 0;
 }
@@ -60,21 +63,39 @@ static int restore_crunch_context(struct crunch_sigframe __user *frame)
 
 #ifdef CONFIG_IWMMXT
 
-static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame)
+static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame)
 {
        char kbuf[sizeof(*frame) + 8];
        struct iwmmxt_sigframe *kframe;
+       int err = 0;
 
        /* the iWMMXt context must be 64 bit aligned */
        kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
-       kframe->magic = IWMMXT_MAGIC;
-       kframe->size = IWMMXT_STORAGE_SIZE;
-       iwmmxt_task_copy(current_thread_info(), &kframe->storage);
-       return __copy_to_user(frame, kframe, sizeof(*frame));
+
+       if (test_thread_flag(TIF_USING_IWMMXT)) {
+               kframe->magic = IWMMXT_MAGIC;
+               kframe->size = IWMMXT_STORAGE_SIZE;
+               iwmmxt_task_copy(current_thread_info(), &kframe->storage);
+
+               err = __copy_to_user(frame, kframe, sizeof(*frame));
+       } else {
+               /*
+                * For bug-compatibility with older kernels, some space
+                * has to be reserved for iWMMXt even if it's not used.
+                * Set the magic and size appropriately so that properly
+                * written userspace can skip it reliably:
+                */
+               __put_user_error(DUMMY_MAGIC, &frame->magic, err);
+               __put_user_error(IWMMXT_STORAGE_SIZE, &frame->size, err);
+       }
+
+       return err;
 }
 
-static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
+static int restore_iwmmxt_context(char __user **auxp)
 {
+       struct iwmmxt_sigframe __user *frame =
+               (struct iwmmxt_sigframe __user *)*auxp;
        char kbuf[sizeof(*frame) + 8];
        struct iwmmxt_sigframe *kframe;
 
@@ -82,10 +103,28 @@ static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
        kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7);
        if (__copy_from_user(kframe, frame, sizeof(*frame)))
                return -1;
-       if (kframe->magic != IWMMXT_MAGIC ||
-           kframe->size != IWMMXT_STORAGE_SIZE)
+
+       /*
+        * For non-iWMMXt threads: a single iwmmxt_sigframe-sized dummy
+        * block is discarded for compatibility with setup_sigframe() if
+        * present, but we don't mandate its presence.  If some other
+        * magic is here, it's not for us:
+        */
+       if (!test_thread_flag(TIF_USING_IWMMXT) &&
+           kframe->magic != DUMMY_MAGIC)
+               return 0;
+
+       if (kframe->size != IWMMXT_STORAGE_SIZE)
                return -1;
-       iwmmxt_task_restore(current_thread_info(), &kframe->storage);
+
+       if (test_thread_flag(TIF_USING_IWMMXT)) {
+               if (kframe->magic != IWMMXT_MAGIC)
+                       return -1;
+
+               iwmmxt_task_restore(current_thread_info(), &kframe->storage);
+       }
+
+       *auxp += IWMMXT_STORAGE_SIZE;
        return 0;
 }
 
@@ -108,8 +147,10 @@ static int preserve_vfp_context(struct vfp_sigframe __user *frame)
        return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc);
 }
 
-static int restore_vfp_context(struct vfp_sigframe __user *frame)
+static int restore_vfp_context(char __user **auxp)
 {
+       struct vfp_sigframe __user *frame =
+               (struct vfp_sigframe __user *)*auxp;
        unsigned long magic;
        unsigned long size;
        int err = 0;
@@ -122,6 +163,7 @@ static int restore_vfp_context(struct vfp_sigframe __user *frame)
        if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE)
                return -EINVAL;
 
+       *auxp += size;
        return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc);
 }
 
@@ -142,7 +184,7 @@ struct rt_sigframe {
 
 static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 {
-       struct aux_sigframe __user *aux;
+       char __user *aux;
        sigset_t set;
        int err;
 
@@ -170,18 +212,18 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 
        err |= !valid_user_regs(regs);
 
-       aux = (struct aux_sigframe __user *) sf->uc.uc_regspace;
+       aux = (char __user *) sf->uc.uc_regspace;
 #ifdef CONFIG_CRUNCH
        if (err == 0)
-               err |= restore_crunch_context(&aux->crunch);
+               err |= restore_crunch_context(&aux);
 #endif
 #ifdef CONFIG_IWMMXT
-       if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
-               err |= restore_iwmmxt_context(&aux->iwmmxt);
+       if (err == 0)
+               err |= restore_iwmmxt_context(&aux);
 #endif
 #ifdef CONFIG_VFP
        if (err == 0)
-               err |= restore_vfp_context(&aux->vfp);
+               err |= restore_vfp_context(&aux);
 #endif
 
        return err;
@@ -287,7 +329,7 @@ setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
                err |= preserve_crunch_context(&aux->crunch);
 #endif
 #ifdef CONFIG_IWMMXT
-       if (err == 0 && test_thread_flag(TIF_USING_IWMMXT))
+       if (err == 0)
                err |= preserve_iwmmxt_context(&aux->iwmmxt);
 #endif
 #ifdef CONFIG_VFP