proc_misc.c bug

[David Mosberger <davidm@napali.hpl.hp.com>]

interrupts_open() can easily try to kmalloc() more memory than
supported by kmalloc.  E.g., with 16KB page size and NR_CPUS==64, it
would try to allocate 147456 bytes.

The workaround below is to allocate 4KB per 8 CPUs.  Not really a
solution, but the fundamental problem is that /proc/interrupts
shouldn't use a fixed buffer size in the first place.  I suppose
another solution would be to use vmalloc() instead.  It all feels like
bandaids though.

	--david

===== fs/proc/proc_misc.c 1.71 vs edited =====
--- 1.71/fs/proc/proc_misc.c	Sat Mar 22 22:14:49 2003
+++ edited/fs/proc/proc_misc.c	Thu Apr 10 14:35:16 2003
@@ -388,7 +388,7 @@
 extern int show_interrupts(struct seq_file *p, void *v);
 static int interrupts_open(struct inode *inode, struct file *file)
 {
-	unsigned size = PAGE_SIZE * (1 + NR_CPUS / 8);
+	unsigned size = 4096 * (1 + NR_CPUS / 8);
 	char *buf = kmalloc(size, GFP_KERNEL);
 	struct seq_file *m;
 	int res;