[xen master] common/device_tree.c: unflatten_device_tree() propagate errors

[patchbot@xxxxxxx]

commit 3ec9528a8262dd461718881d251fba01d3e662fa
Author:     Vikram Garhwal <vikram.garhwal@xxxxxxx>
AuthorDate: Tue Sep 5 18:16:12 2023 -0700
Commit:     Stefano Stabellini <stefano.stabellini@xxxxxxx>
CommitDate: Tue Sep 5 18:24:20 2023 -0700

    common/device_tree.c: unflatten_device_tree() propagate errors
    
    This will be useful in dynamic node programming when new dt nodes are 
unflattend
    during runtime. Invalid device tree node related errors should be propagated
    back to the caller.
    
    Signed-off-by: Vikram Garhwal <vikram.garhwal@xxxxxxx>
    Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
    Acked-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
---
 xen/common/device_tree.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c
index 7c6b41c3b4..b6d9f018c6 100644
--- a/xen/common/device_tree.c
+++ b/xen/common/device_tree.c
@@ -2110,6 +2110,9 @@ static int __init __unflatten_device_tree(const void *fdt,
     /* First pass, scan for size */
     start = ((unsigned long)fdt) + fdt_off_dt_struct(fdt);
     size = unflatten_dt_node(fdt, 0, &start, NULL, NULL, 0);
+    if ( !size )
+        return -EINVAL;
+
     size = (size | 3) + 1;
 
     dt_dprintk("  size is %#lx allocating...\n", size);
@@ -2127,11 +2130,21 @@ static int __init __unflatten_device_tree(const void 
*fdt,
     start = ((unsigned long)fdt) + fdt_off_dt_struct(fdt);
     unflatten_dt_node(fdt, mem, &start, NULL, &allnextp, 0);
     if ( be32_to_cpup((__be32 *)start) != FDT_END )
-        printk(XENLOG_WARNING "Weird tag at end of tree: %08x\n",
+    {
+        printk(XENLOG_ERR "Weird tag at end of tree: %08x\n",
                   *((u32 *)start));
+        xfree((void *)mem);
+        return -EINVAL;
+    }
+
     if ( be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeefU )
-        printk(XENLOG_WARNING "End of tree marker overwritten: %08x\n",
+    {
+        printk(XENLOG_ERR "End of tree marker overwritten: %08x\n",
                   be32_to_cpu(((__be32 *)mem)[size / 4]));
+        xfree((void *)mem);
+        return -EINVAL;
+    }
+
     *allnextp = NULL;
 
     dt_dprintk(" <- unflatten_device_tree()\n");
--
generated by git-patchbot for /home/xen/git/xen.git#master