From: Jeremy Kerr <jk@ozlabs.org>
Date: Thu, 1 Aug 2013 07:25:53 +0000 (+0800)
Subject: discover: fix segfault on failed boot image load
X-Git-Tag: v1.0.0~536
X-Git-Url: https://git.ozlabs.org/?p=petitboot;a=commitdiff_plain;h=f9a63d3a640cb30a12598cedc0dd7d8b6fc5b4de;hp=404c07fc44449be7b011d1961280ef9c96e0760d

discover: fix segfault on failed boot image load

If the boot image fails to load, we end up calling talloc_free on an
unitialised are of stack (boot_task.local_initrd).

Move the initialisers a little earlier, so we always NULL pointers
before potentially freeing.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
---

diff --git a/discover/boot.c b/discover/boot.c
index ed30ef9..e57810d 100644
--- a/discover/boot.c
+++ b/discover/boot.c
@@ -321,6 +321,9 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 
 	result = -1;
 
+	boot_task.local_initrd = NULL;
+	boot_task.local_dtb = NULL;
+
 	update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 			"loading kernel");
 	boot_task.local_image = load_url(NULL, image, &clean_image);
@@ -330,7 +333,6 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 		goto no_load;
 	}
 
-	boot_task.local_initrd = NULL;
 	if (initrd) {
 		update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 				"loading initrd");
@@ -342,7 +344,6 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 		}
 	}
 
-	boot_task.local_dtb = NULL;
 	if (dtb) {
 		update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 				"loading device tree");