diff options
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 42 |
1 files changed, 21 insertions, 21 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index de981370fbc5..4caf8ed24d65 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -569,7 +569,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr) i_size_write(inode, newsize); inode->i_ctime = inode->i_mtime = CURRENT_TIME; } - if (newsize < oldsize) { + if (newsize <= oldsize) { loff_t holebegin = round_up(newsize, PAGE_SIZE); unmap_mapping_range(inode->i_mapping, holebegin, 0, 1); shmem_truncate_range(inode, newsize, (loff_t)-1); @@ -2451,6 +2451,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s return -ENOMEM; } inode->i_op = &shmem_short_symlink_operations; + inode->i_link = info->symlink; } else { error = shmem_getpage(inode, 0, &page, SGP_WRITE, NULL); if (error) { @@ -2474,30 +2475,23 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s return 0; } -static void *shmem_follow_short_symlink(struct dentry *dentry, struct nameidata *nd) -{ - nd_set_link(nd, SHMEM_I(d_inode(dentry))->symlink); - return NULL; -} - -static void *shmem_follow_link(struct dentry *dentry, struct nameidata *nd) +static const char *shmem_follow_link(struct dentry *dentry, void **cookie) { struct page *page = NULL; int error = shmem_getpage(d_inode(dentry), 0, &page, SGP_READ, NULL); - nd_set_link(nd, error ? ERR_PTR(error) : kmap(page)); - if (page) - unlock_page(page); - return page; + if (error) + return ERR_PTR(error); + unlock_page(page); + *cookie = page; + return kmap(page); } -static void shmem_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) +static void shmem_put_link(struct inode *unused, void *cookie) { - if (!IS_ERR(nd_get_link(nd))) { - struct page *page = cookie; - kunmap(page); - mark_page_accessed(page); - page_cache_release(page); - } + struct page *page = cookie; + kunmap(page); + mark_page_accessed(page); + page_cache_release(page); } #ifdef CONFIG_TMPFS_XATTR @@ -2642,7 +2636,7 @@ static ssize_t shmem_listxattr(struct dentry *dentry, char *buffer, size_t size) static const struct inode_operations shmem_short_symlink_operations = { .readlink = generic_readlink, - .follow_link = shmem_follow_short_symlink, + .follow_link = simple_follow_link, #ifdef CONFIG_TMPFS_XATTR .setxattr = shmem_setxattr, .getxattr = shmem_getxattr, @@ -3401,7 +3395,13 @@ int shmem_zero_setup(struct vm_area_struct *vma) struct file *file; loff_t size = vma->vm_end - vma->vm_start; - file = shmem_file_setup("dev/zero", size, vma->vm_flags); + /* + * Cloning a new file under mmap_sem leads to a lock ordering conflict + * between XFS directory reading and selinux: since this file is only + * accessible to the user through its mapping, use S_PRIVATE flag to + * bypass file security, in the same way as shmem_kernel_file_setup(). + */ + file = __shmem_file_setup("dev/zero", size, vma->vm_flags, S_PRIVATE); if (IS_ERR(file)) return PTR_ERR(file); |