[PATCH] kdump: Fix exported size of vmcoreinfo note

Vivek Goyal vgoyal at redhat.com
Tue Jan 14 14:33:11 EST 2014

Right now we seem to be exporting the max data size contained inside
vmcoreinfo note. But this does not include the size of meta data around
vmcore info data. Like name of the note and starting and ending elf_note.

I think user space expects total size and that size is put in PT_NOTE
elf header. Things seem to be fine so far because we are not using
vmcoreinfo note to the maximum capacity. But as it starts filling up,
to capacity, at some point of time, problem will be visible.

Signed-off-by: Vivek Goyal <vgoyal at redhat.com>
 kernel/ksysfs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6/kernel/ksysfs.c
--- linux-2.6.orig/kernel/ksysfs.c	2014-01-14 14:09:42.107767503 -0500
+++ linux-2.6/kernel/ksysfs.c	2014-01-14 14:15:24.385510314 -0500
@@ -126,7 +126,7 @@ static ssize_t vmcoreinfo_show(struct ko
 	return sprintf(buf, "%lx %x\n",
-		       (unsigned int)vmcoreinfo_max_size);
+		       (unsigned int)sizeof(vmcoreinfo_note));

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