Re: 2.6.13-mm3 [OOPS] vfs, page_owner, full reproductively, badness in vsnprintf

Michal Piotrowski
2005-09-12T22:57:03Z

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Andrew Morton napisał(a):
> Michal Piotrowski <michal.k.k.piotrowski@gmail.com> wrote:
>
>>Hi,

>>Thanks, patch solved problem.
>
>
> Thanks.
>
>
>>Here is version, that clean apply on 2.6.13-mm3. Can you review it?
>
>
> That patch is all wordwrapped.

Ups, sorry. This should be good.
>
> How doe sit differe from Alex's patch?
>
>

Alex's patch doesn't apply clean on 2.6.13-mm3.

Regards,
Michal Piotrowski

diff -uprN -X linux-mm-clean/Documentation/dontdiff
linux-mm-clean/fs/proc/proc_misc.c linux-mm/fs/proc/proc_misc.c
--- linux-mm-clean/fs/proc/proc_misc.c 2005-09-12 23:02:10.000000000 +0200
+++ linux-mm/fs/proc/proc_misc.c 2005-09-12 22:52:51.000000000 +0200
@@ -567,6 +567,7 @@ read_page_owner(struct file *file, char
char namebuf[128];
unsigned long offset = 0, symsize;
int i;
+ ssize_t num_written = 0;

pfn = min_low_pfn + *ppos;
page = pfn_to_page(pfn);
@@ -587,23 +588,41 @@ read_page_owner(struct file *file, char
kbuf = kmalloc(count, GFP_KERNEL);
if (!kbuf)
return -ENOMEM;
+ ret = snprintf(kbuf, count, "Page allocated via order %d, mask
0x%x\n", page->order, page->gfp_mask);
+ if (ret >= count) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ num_written = ret;

- ret = snprintf(kbuf, 1024, "Page allocated via order %d, mask 0x%x\n",
- page->order, page->gfp_mask);

for (i = 0; i < 8; i++) {
if (!page->trace[i])
break;
symname = kallsyms_lookup(page->trace[i], &symsize, &offset,
&modname, namebuf);
- ret += snprintf(kbuf + ret, count - ret, "[0x%lx] %s+%lu\n",
+ ret = snprintf(kbuf + num_written, count - num_written,
"[0x%lx] %s+%lu\n",
page->trace[i], namebuf, offset);
+ if (ret >= count - num_written) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ num_written += ret;
+
}
+ ret = snprintf(kbuf + num_written, count - num_written, "\n");
+ if (ret >= count - num_written) {
+ ret = -ENOMEM;
+ goto out;
+ }

- ret += snprintf(kbuf + ret, count -ret, "\n");
+ num_written += ret;
+ ret = num_written;

if (copy_to_user(buf, kbuf, ret))
ret = -EFAULT;

+out:
kfree(kbuf);
return ret;
}

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diff -uprN -X linux-mm-clean/Documentation/dontdiff linux-mm-clean/fs/proc/proc_misc.c linux-mm/fs/proc/proc_misc.c
--- linux-mm-clean/fs/proc/proc_misc.c 2005-09-12 23:02:10.000000000 +0200
+++ linux-mm/fs/proc/proc_misc.c 2005-09-12 22:52:51.000000000 +0200
@@ -567,6 +567,7 @@ read_page_owner(struct file *file, char
char namebuf[128];
unsigned long offset = 0, symsize;
int i;
+ ssize_t num_written = 0;

pfn = min_low_pfn + *ppos;
page = pfn_to_page(pfn);
@@ -587,23 +588,41 @@ read_page_owner(struct file *file, char
kbuf = kmalloc(count, GFP_KERNEL);
if (!kbuf)
return -ENOMEM;
+ ret = snprintf(kbuf, count, "Page allocated via order %d, mask 0x%x\n", page->order, page->gfp_mask);
+ if (ret >= count) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ num_written = ret;

- ret = snprintf(kbuf, 1024, "Page allocated via order %d, mask 0x%x\n",
- page->order, page->gfp_mask);

for (i = 0; i < 8; i++) {
if (!page->trace[i])
break;
symname = kallsyms_lookup(page->trace[i], &symsize, &offset, &modname, namebuf);
- ret += snprintf(kbuf + ret, count - ret, "[0x%lx] %s+%lu\n",
+ ret = snprintf(kbuf + num_written, count - num_written, "[0x%lx] %s+%lu\n",
page->trace[i], namebuf, offset);
+ if (ret >= count - num_written) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ num_written += ret;
+
}
+ ret = snprintf(kbuf + num_written, count - num_written, "\n");
+ if (ret >= count - num_written) {
+ ret = -ENOMEM;
+ goto out;
+ }

- ret += snprintf(kbuf + ret, count -ret, "\n");
+ num_written += ret;
+ ret = num_written;

if (copy_to_user(buf, kbuf, ret))
ret = -EFAULT;

+out:
kfree(kbuf);
return ret;
}