openwrtv3/target/linux/ixp4xx/patches-3.10/162-wg302v1_mem_fixup.patch
John Crispin 83381c5c8f ixp4xx: Don't overwrite memory in wg302v1_fixup()
wg302v1_fixup() looks for the ATAG_CMDLINE atag, it doesn't find it and
so it takes the last atag in the list and overwrites non allocated
memory.

The side effects are corrupted vital data and a kernel that doesn't
boot. More details here https://dev.openwrt.org/ticket/18356

The fix appends the fixup to the command line and updates the atag only
when it finds it.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>

SVN-Revision: 43320
2014-11-19 14:09:19 +00:00

38 lines
973 B
Diff

--- a/arch/arm/mach-ixp4xx/wg302v1-setup.c
+++ b/arch/arm/mach-ixp4xx/wg302v1-setup.c
@@ -117,6 +117,35 @@ static struct platform_device *wg302v1_d
&wg302v1_eth[0],
};
+static char wg302v1_mem_fixup[] __initdata = " mem=32M";
+
+static void __init wg302v1_fixup(struct tag *tags, char **cmdline,
+ struct meminfo *mi)
+{
+ struct tag *t = tags;
+ char *p = *cmdline;
+ size_t fixlen, cmdlen;
+
+ /* Find the end of the tags table, taking note of any cmdline tag. */
+ for (; t->hdr.size; t = tag_next(t)) {
+ if (t->hdr.tag == ATAG_CMDLINE) {
+ p = t->u.cmdline.cmdline;
+ }
+ }
+
+ fixlen = strlen(wg302v1_mem_fixup);
+ cmdlen = strlen(p);
+ if (fixlen + cmdlen >= COMMAND_LINE_SIZE)
+ return;
+
+ /* append the fixup to the cmdline */
+ memmove(p + cmdlen, wg302v1_mem_fixup, fixlen + 1);
+
+ /* Adjust the size of the atag if there was one */
+ if (t->hdr.size)
+ t->hdr.size += fixlen;
+}
+
static void __init wg302v1_init(void)
{
ixp4xx_sys_init();