lkml.org 
[lkml]   [2014]   [Jul]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] NoMoreModuleVmalloc - Try alloc_pages_exact before vmalloc, if fails do vmalloc
Convert vmalloc() call to alloc_pages_exact(). If alloc_pages_exact() fails,
then fall back to vmalloc(). If the address is a vmalloc address, then
call vfree(), otherwise call free_pages_exact().

Signed-off-by: Lucas Tanure <tanure@linux.com>
---
kernel/module.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/kernel/module.c b/kernel/module.c
index ae79ce6..50c1e77 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2484,6 +2484,7 @@ static int copy_module_from_user(const void __user *umod, unsigned long len,
struct load_info *info)
{
int err;
+ bool alloc_from_vmalloc = false;

info->len = len;
if (info->len < sizeof(*(info->hdr)))
@@ -2494,12 +2495,19 @@ static int copy_module_from_user(const void __user *umod, unsigned long len,
return err;

/* Suck in entire file: we'll want most of it. */
- info->hdr = vmalloc(info->len);
- if (!info->hdr)
- return -ENOMEM;
+ info->hdr = alloc_pages_exact(info->len, GFP_KERNEL);
+ if (!info->hdr) {
+ info->hdr = vmalloc(info->len);
+ if (!info->hdr)
+ return -ENOMEM;
+ alloc_from_vmalloc = true;
+ }

if (copy_from_user(info->hdr, umod, info->len) != 0) {
- vfree(info->hdr);
+ if(alloc_from_vmalloc)
+ vfree(info->hdr);
+ else
+ free_pages_exact(info->hdr,info->len);
return -EFAULT;
}

--
2.0.1


\
 
 \ /
  Last update: 2014-07-13 15:41    [W:0.152 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site