Commit 198c9985 authored Mar 05, 2019 by Chao Yu Committed by Greg Kroah-Hartman Apr 05, 2019

f2fs: fix to adapt small inline xattr space in __find_inline_xattr()



[ Upstream commit 2c28aba8b2e2a51749fa66e01b68e1cd5b53e022 ]

With below testcase, we will fail to find existed xattr entry:

1. mkfs.f2fs -O extra_attr -O flexible_inline_xattr /dev/zram0
2. mount -t f2fs -o inline_xattr_size=1 /dev/zram0 /mnt/f2fs/
3. touch /mnt/f2fs/file
4. setfattr -n "user.name" -v 0 /mnt/f2fs/file
5. getfattr -n "user.name" /mnt/f2fs/file

/mnt/f2fs/file: user.name: No such attribute

The reason is for inode which has very small inline xattr size,
__find_inline_xattr() will fail to traverse any entry due to first
entry may not be loaded from xattr node yet, later, we may skip to
check entire xattr datas in __find_xattr(), result in such wrong
condition.

This patch adds condition to check such case to avoid this issue.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 56bb66c5

fs/f2fs/xattr.c

+10 −3

Original line number	Diff line number	Diff line
		@@ -227,11 +227,11 @@ static struct f2fs_xattr_entry __find_inline_xattr(struct inode inode,
		{
		struct f2fs_xattr_entry *entry;
		unsigned int inline_size = inline_xattr_size(inode);
		void *max_addr = base_addr + inline_size;

		list_for_each_xattr(entry, base_addr) {
		if ((void *)entry + sizeof(__u32) > base_addr + inline_size \|\|
		(void *)XATTR_NEXT_ENTRY(entry) + sizeof(__u32) >
		base_addr + inline_size) {
		if ((void *)entry + sizeof(__u32) > max_addr \|\|
		(void *)XATTR_NEXT_ENTRY(entry) > max_addr) {
		*last_addr = entry;
		return NULL;
		}
		@@ -242,6 +242,13 @@ static struct f2fs_xattr_entry __find_inline_xattr(struct inode inode,
		if (!memcmp(entry->e_name, name, len))
		break;
		}

		/* inline xattr header or entry across max inline xattr size */
		if (IS_XATTR_LAST_ENTRY(entry) &&
		(void *)entry + sizeof(__u32) > max_addr) {
		*last_addr = entry;
		return NULL;
		}
		return entry;
		}