mirror of
https://github.com/adulau/aha.git
synced 2024-12-27 19:26:25 +00:00
vfs: ensure page symlinks are NUL-terminated
On-disk data corruption could cause a page link to have its i_size set to PAGE_SIZE (or a multiple thereof) and its contents all non-NUL. NUL-terminate the link name to ensure this doesn't cause further problems for the kernel. Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Duane Griffin <duaneg@dghda.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
parent
035146851c
commit
ebd09abbd9
1 changed files with 5 additions and 2 deletions
|
@ -2786,13 +2786,16 @@ int vfs_follow_link(struct nameidata *nd, const char *link)
|
|||
/* get the link contents into pagecache */
|
||||
static char *page_getlink(struct dentry * dentry, struct page **ppage)
|
||||
{
|
||||
struct page * page;
|
||||
char *kaddr;
|
||||
struct page *page;
|
||||
struct address_space *mapping = dentry->d_inode->i_mapping;
|
||||
page = read_mapping_page(mapping, 0, NULL);
|
||||
if (IS_ERR(page))
|
||||
return (char*)page;
|
||||
*ppage = page;
|
||||
return kmap(page);
|
||||
kaddr = kmap(page);
|
||||
nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1);
|
||||
return kaddr;
|
||||
}
|
||||
|
||||
int page_readlink(struct dentry *dentry, char __user *buffer, int buflen)
|
||||
|
|
Loading…
Reference in a new issue