diff mbox series

[XEN,v12,02/20] common/device_tree.c: unflatten_device_tree() propagate errors

Message ID 20230906011631.30310-3-vikram.garhwal@amd.com (mailing list archive)
State New, archived
Headers show
Series dynamic node programming using overlay dtbo | expand

Commit Message

Vikram Garhwal Sept. 6, 2023, 1:16 a.m. UTC 
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@amd.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>

---
Changes from v9:
    Replace __be64 with void.
Changes from v7:
    Free allocated memory in case of errors when calling unflatten_dt_node.
---
---
 xen/common/device_tree.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)
diff mbox series

Patch

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");