discover/boot: Copy local paths before running boot hooks
authorJeremy Kerr <jk@ozlabs.org>
Thu, 5 Dec 2013 06:54:13 +0000 (14:54 +0800)
committerJeremy Kerr <jk@ozlabs.org>
Thu, 5 Dec 2013 07:11:46 +0000 (15:11 +0800)
We're seeing a crash when boot hooks are specifying new resources, as
boot_hook_update_param will write to a NULL struct load_url_result.

Instead of writing the updated values to the struct, copy the local
parts of the result to a separate string, which the boot hooks are free
to update.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
discover/boot.c

index 83bcc7bfe8ce5c2b96d54f537d689fe21ebb4a9e..0d61f0efc785295852c659914461bd656e4865fe 100644 (file)
@@ -32,6 +32,9 @@ struct boot_task {
        struct load_url_result *image;
        struct load_url_result *initrd;
        struct load_url_result *dtb;
+       const char *local_image;
+       const char *local_initrd;
+       const char *local_dtb;
        const char *args;
        boot_status_fn status_fn;
        void *status_arg;
@@ -55,16 +58,16 @@ static int kexec_load(struct boot_task *boot_task)
        *p++ = pb_system_apps.kexec;    /* 1 */
        *p++ = "-l";                    /* 2 */
 
-       if (boot_task->initrd) {
+       if (boot_task->local_initrd) {
                s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
-                               boot_task->initrd->local);
+                               boot_task->local_initrd);
                assert(s_initrd);
                *p++ = s_initrd;         /* 3 */
        }
 
-       if (boot_task->dtb) {
+       if (boot_task->local_dtb) {
                s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
-                                               boot_task->dtb->local);
+                                               boot_task->local_dtb);
                assert(s_dtb);
                *p++ = s_dtb;            /* 4 */
        }
@@ -76,7 +79,7 @@ static int kexec_load(struct boot_task *boot_task)
                *p++ = s_args;          /* 5 */
        }
 
-       *p++ = boot_task->image->local; /* 6 */
+       *p++ = boot_task->local_image;  /* 6 */
        *p++ = NULL;                    /* 7 */
 
        result = process_run_simple_argv(boot_task, argv);
@@ -151,9 +154,9 @@ static void boot_hook_update_param(void *ctx, struct boot_task *task,
                const char *name;
                const char **p;
        } *param, params[] = {
-               { "boot_image",         &task->image->local },
-               { "boot_initrd",        &task->initrd->local },
-               { "boot_dtb",           &task->dtb->local },
+               { "boot_image",         &task->local_image },
+               { "boot_initrd",        &task->local_initrd },
+               { "boot_dtb",           &task->local_dtb },
                { "boot_args",          &task->args },
                { NULL, NULL },
        };
@@ -201,11 +204,11 @@ static void boot_hook_setenv(struct boot_task *task)
        unsetenv("boot_dtb");
        unsetenv("boot_args");
 
-       setenv("boot_image", task->image->local, 1);
-       if (task->initrd)
-               setenv("boot_initrd", task->initrd->local, 1);
-       if (task->dtb)
-               setenv("boot_dtb", task->dtb->local, 1);
+       setenv("boot_image", task->local_image, 1);
+       if (task->local_initrd)
+               setenv("boot_initrd", task->local_initrd, 1);
+       if (task->local_dtb)
+               setenv("boot_dtb", task->local_dtb, 1);
        if (task->args)
                setenv("boot_args", task->args, 1);
 }
@@ -362,6 +365,12 @@ static void boot_process(struct load_url_result *result, void *data)
                        check_load(task, "dtb", task->dtb))
                goto no_load;
 
+       /* we make a copy of the local paths, as the boot hooks might update
+        * and/or create these */
+       task->local_image = task->image ? task->image->local : NULL;
+       task->local_initrd = task->initrd ? task->initrd->local : NULL;
+       task->local_dtb = task->dtb ? task->dtb->local : NULL;
+
        run_boot_hooks(task);
 
        update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,