linux-stable/fs/f2fs/xattr.h

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// SPDX-License-Identifier: GPL-2.0
/*
* fs/f2fs/xattr.h
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* Portions of this code from linux/fs/ext2/xattr.h
*
* On-disk format of extended attributes for the ext2 filesystem.
*
* (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
*/
#ifndef __F2FS_XATTR_H__
#define __F2FS_XATTR_H__
#include <linux/init.h>
#include <linux/xattr.h>
/* Magic value in attribute blocks */
#define F2FS_XATTR_MAGIC 0xF2F52011
/* Maximum number of references to one attribute block */
#define F2FS_XATTR_REFCOUNT_MAX 1024
/* Name indexes */
#define F2FS_SYSTEM_ADVISE_NAME "system.advise"
#define F2FS_XATTR_INDEX_USER 1
#define F2FS_XATTR_INDEX_POSIX_ACL_ACCESS 2
#define F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT 3
#define F2FS_XATTR_INDEX_TRUSTED 4
#define F2FS_XATTR_INDEX_LUSTRE 5
#define F2FS_XATTR_INDEX_SECURITY 6
#define F2FS_XATTR_INDEX_ADVISE 7
/* Should be same as EXT4_XATTR_INDEX_ENCRYPTION */
#define F2FS_XATTR_INDEX_ENCRYPTION 9
#define F2FS_XATTR_NAME_ENCRYPTION_CONTEXT "c"
struct f2fs_xattr_header {
__le32 h_magic; /* magic number for identification */
__le32 h_refcount; /* reference count */
__u32 h_reserved[4]; /* zero right now */
};
struct f2fs_xattr_entry {
__u8 e_name_index;
__u8 e_name_len;
__le16 e_value_size; /* size of attribute value */
char e_name[0]; /* attribute name */
};
#define XATTR_HDR(ptr) ((struct f2fs_xattr_header *)(ptr))
#define XATTR_ENTRY(ptr) ((struct f2fs_xattr_entry *)(ptr))
#define XATTR_FIRST_ENTRY(ptr) (XATTR_ENTRY(XATTR_HDR(ptr) + 1))
#define XATTR_ROUND (3)
#define XATTR_ALIGN(size) (((size) + XATTR_ROUND) & ~XATTR_ROUND)
#define ENTRY_SIZE(entry) (XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + \
(entry)->e_name_len + le16_to_cpu((entry)->e_value_size)))
#define XATTR_NEXT_ENTRY(entry) ((struct f2fs_xattr_entry *)((char *)(entry) +\
ENTRY_SIZE(entry)))
#define IS_XATTR_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
#define list_for_each_xattr(entry, addr) \
for (entry = XATTR_FIRST_ENTRY(addr);\
!IS_XATTR_LAST_ENTRY(entry);\
entry = XATTR_NEXT_ENTRY(entry))
#define VALID_XATTR_BLOCK_SIZE (PAGE_SIZE - sizeof(struct node_footer))
#define XATTR_PADDING_SIZE (sizeof(__u32))
f2fs: fix to avoid accessing xattr across the boundary When we traverse xattr entries via __find_xattr(), if the raw filesystem content is faked or any hardware failure occurs, out-of-bound error can be detected by KASAN. Fix the issue by introducing boundary check. [ 38.402878] c7 1827 BUG: KASAN: slab-out-of-bounds in f2fs_getxattr+0x518/0x68c [ 38.402891] c7 1827 Read of size 4 at addr ffffffc0b6fb35dc by task [ 38.402935] c7 1827 Call trace: [ 38.402952] c7 1827 [<ffffff900809003c>] dump_backtrace+0x0/0x6bc [ 38.402966] c7 1827 [<ffffff9008090030>] show_stack+0x20/0x2c [ 38.402981] c7 1827 [<ffffff900871ab10>] dump_stack+0xfc/0x140 [ 38.402995] c7 1827 [<ffffff9008325c40>] print_address_description+0x80/0x2d8 [ 38.403009] c7 1827 [<ffffff900832629c>] kasan_report_error+0x198/0x1fc [ 38.403022] c7 1827 [<ffffff9008326104>] kasan_report_error+0x0/0x1fc [ 38.403037] c7 1827 [<ffffff9008325000>] __asan_load4+0x1b0/0x1b8 [ 38.403051] c7 1827 [<ffffff90085fcc44>] f2fs_getxattr+0x518/0x68c [ 38.403066] c7 1827 [<ffffff90085fc508>] f2fs_xattr_generic_get+0xb0/0xd0 [ 38.403080] c7 1827 [<ffffff9008395708>] __vfs_getxattr+0x1f4/0x1fc [ 38.403096] c7 1827 [<ffffff9008621bd0>] inode_doinit_with_dentry+0x360/0x938 [ 38.403109] c7 1827 [<ffffff900862d6cc>] selinux_d_instantiate+0x2c/0x38 [ 38.403123] c7 1827 [<ffffff900861b018>] security_d_instantiate+0x68/0x98 [ 38.403136] c7 1827 [<ffffff9008377db8>] d_splice_alias+0x58/0x348 [ 38.403149] c7 1827 [<ffffff900858d16c>] f2fs_lookup+0x608/0x774 [ 38.403163] c7 1827 [<ffffff900835eacc>] lookup_slow+0x1e0/0x2cc [ 38.403177] c7 1827 [<ffffff9008367fe0>] walk_component+0x160/0x520 [ 38.403190] c7 1827 [<ffffff9008369ef4>] path_lookupat+0x110/0x2b4 [ 38.403203] c7 1827 [<ffffff900835dd38>] filename_lookup+0x1d8/0x3a8 [ 38.403216] c7 1827 [<ffffff900835eeb0>] user_path_at_empty+0x54/0x68 [ 38.403229] c7 1827 [<ffffff9008395f44>] SyS_getxattr+0xb4/0x18c [ 38.403241] c7 1827 [<ffffff9008084200>] el0_svc_naked+0x34/0x38 Signed-off-by: Randall Huang <huangrandall@google.com> [Jaegeuk Kim: Fix wrong ending boundary] Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-04-11 08:26:46 +00:00
#define XATTR_SIZE(x,i) (((x) ? VALID_XATTR_BLOCK_SIZE : 0) + \
(inline_xattr_size(i)))
#define MIN_OFFSET(i) XATTR_ALIGN(inline_xattr_size(i) + \
VALID_XATTR_BLOCK_SIZE)
#define MAX_VALUE_LEN(i) (MIN_OFFSET(i) - \
sizeof(struct f2fs_xattr_header) - \
sizeof(struct f2fs_xattr_entry))
f2fs: fix to do sanity check with inode.i_inline_xattr_size As Paul Bandha reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202709 When I run the poc on the mounted f2fs img I get a buffer overflow in read_inline_xattr due to there being no sanity check on the value of i_inline_xattr_size. I created the img by just modifying the value of i_inline_xattr_size in the inode: i_name [test1.txt] i_ext: fofs:0 blkaddr:0 len:0 i_extra_isize [0x 18 : 24] i_inline_xattr_size [0x ffff : 65535] i_addr[ofs] [0x 0 : 0] mkdir /mnt/f2fs mount ./f2fs1.img /mnt/f2fs gcc poc.c -o poc ./poc int main() { int y = syscall(SYS_listxattr, "/mnt/f2fs/test1.txt", NULL, 0); printf("ret %d", y); printf("errno: %d\n", errno); } BUG: KASAN: slab-out-of-bounds in read_inline_xattr+0x18f/0x260 Read of size 262140 at addr ffff88011035efd8 by task f2fs1poc/3263 CPU: 0 PID: 3263 Comm: f2fs1poc Not tainted 4.18.0-custom #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0x71/0xab print_address_description+0x83/0x250 kasan_report+0x213/0x350 memcpy+0x1f/0x50 read_inline_xattr+0x18f/0x260 read_all_xattrs+0xba/0x190 f2fs_listxattr+0x9d/0x3f0 listxattr+0xb2/0xd0 path_listxattr+0x93/0xe0 do_syscall_64+0x9d/0x220 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Let's add sanity check for inode.i_inline_xattr_size during f2fs_iget() to avoid this issue. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-03-04 09:19:04 +00:00
#define MAX_INLINE_XATTR_SIZE \
(DEF_ADDRS_PER_INODE - \
F2FS_TOTAL_EXTRA_ATTR_SIZE / sizeof(__le32) - \
DEF_INLINE_RESERVED_SIZE - \
MIN_INLINE_DENTRY_SIZE / sizeof(__le32))
/*
* On-disk structure of f2fs_xattr
* We use inline xattrs space + 1 block for xattr.
*
* +--------------------+
* | f2fs_xattr_header |
* | |
* +--------------------+
* | f2fs_xattr_entry |
* | .e_name_index = 1 |
* | .e_name_len = 3 |
* | .e_value_size = 14 |
* | .e_name = "foo" |
* | "value_of_xattr" |<- value_offs = e_name + e_name_len
* +--------------------+
* | f2fs_xattr_entry |
* | .e_name_index = 4 |
* | .e_name = "bar" |
* +--------------------+
* | |
* | Free |
* | |
* +--------------------+<- MIN_OFFSET
* | node_footer |
* | (nid, ino, offset) |
* +--------------------+
*
**/
#ifdef CONFIG_F2FS_FS_XATTR
extern const struct xattr_handler f2fs_xattr_user_handler;
extern const struct xattr_handler f2fs_xattr_trusted_handler;
extern const struct xattr_handler f2fs_xattr_advise_handler;
extern const struct xattr_handler f2fs_xattr_security_handler;
extern const struct xattr_handler *f2fs_xattr_handlers[];
extern int f2fs_setxattr(struct inode *, int, const char *,
const void *, size_t, struct page *, int);
f2fs: avoid deadlock on init_inode_metadata Previously, init_inode_metadata does not hold any parent directory's inode page. So, f2fs_init_acl can grab its parent inode page without any problem. But, when we use inline_dentry, that page is grabbed during f2fs_add_link, so that we can fall into deadlock condition like below. INFO: task mknod:11006 blocked for more than 120 seconds. Tainted: G OE 3.17.0-rc1+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. mknod D ffff88003fc94580 0 11006 11004 0x00000000 ffff880007717b10 0000000000000002 ffff88003c323220 ffff880007717fd8 0000000000014580 0000000000014580 ffff88003daecb30 ffff88003c323220 ffff88003fc94e80 ffff88003ffbb4e8 ffff880007717ba0 0000000000000002 Call Trace: [<ffffffff8173dc40>] ? bit_wait+0x50/0x50 [<ffffffff8173d4cd>] io_schedule+0x9d/0x130 [<ffffffff8173dc6c>] bit_wait_io+0x2c/0x50 [<ffffffff8173da3b>] __wait_on_bit_lock+0x4b/0xb0 [<ffffffff811640a7>] __lock_page+0x67/0x70 [<ffffffff810acf50>] ? autoremove_wake_function+0x40/0x40 [<ffffffff811652cc>] pagecache_get_page+0x14c/0x1e0 [<ffffffffa029afa9>] get_node_page+0x59/0x130 [f2fs] [<ffffffffa02a63ad>] read_all_xattrs+0x24d/0x430 [f2fs] [<ffffffffa02a6ca2>] f2fs_getxattr+0x52/0xe0 [f2fs] [<ffffffffa02a7481>] f2fs_get_acl+0x41/0x2d0 [f2fs] [<ffffffff8122d847>] get_acl+0x47/0x70 [<ffffffff8122db5a>] posix_acl_create+0x5a/0x150 [<ffffffffa02a7759>] f2fs_init_acl+0x29/0xcb [f2fs] [<ffffffffa0286a8d>] init_inode_metadata+0x5d/0x340 [f2fs] [<ffffffffa029253a>] f2fs_add_inline_entry+0x12a/0x2e0 [f2fs] [<ffffffffa0286ea5>] __f2fs_add_link+0x45/0x4a0 [f2fs] [<ffffffffa028b5b6>] ? f2fs_new_inode+0x146/0x220 [f2fs] [<ffffffffa028b816>] f2fs_mknod+0x86/0xf0 [f2fs] [<ffffffff811e3ec1>] vfs_mknod+0xe1/0x160 [<ffffffff811e4b26>] SyS_mknod+0x1f6/0x200 [<ffffffff81741d7f>] tracesys+0xe1/0xe6 Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-10-14 02:42:53 +00:00
extern int f2fs_getxattr(struct inode *, int, const char *, void *,
size_t, struct page *);
extern ssize_t f2fs_listxattr(struct dentry *, char *, size_t);
#else
#define f2fs_xattr_handlers NULL
static inline int f2fs_setxattr(struct inode *inode, int index,
const char *name, const void *value, size_t size,
struct page *page, int flags)
{
return -EOPNOTSUPP;
}
static inline int f2fs_getxattr(struct inode *inode, int index,
f2fs: avoid deadlock on init_inode_metadata Previously, init_inode_metadata does not hold any parent directory's inode page. So, f2fs_init_acl can grab its parent inode page without any problem. But, when we use inline_dentry, that page is grabbed during f2fs_add_link, so that we can fall into deadlock condition like below. INFO: task mknod:11006 blocked for more than 120 seconds. Tainted: G OE 3.17.0-rc1+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. mknod D ffff88003fc94580 0 11006 11004 0x00000000 ffff880007717b10 0000000000000002 ffff88003c323220 ffff880007717fd8 0000000000014580 0000000000014580 ffff88003daecb30 ffff88003c323220 ffff88003fc94e80 ffff88003ffbb4e8 ffff880007717ba0 0000000000000002 Call Trace: [<ffffffff8173dc40>] ? bit_wait+0x50/0x50 [<ffffffff8173d4cd>] io_schedule+0x9d/0x130 [<ffffffff8173dc6c>] bit_wait_io+0x2c/0x50 [<ffffffff8173da3b>] __wait_on_bit_lock+0x4b/0xb0 [<ffffffff811640a7>] __lock_page+0x67/0x70 [<ffffffff810acf50>] ? autoremove_wake_function+0x40/0x40 [<ffffffff811652cc>] pagecache_get_page+0x14c/0x1e0 [<ffffffffa029afa9>] get_node_page+0x59/0x130 [f2fs] [<ffffffffa02a63ad>] read_all_xattrs+0x24d/0x430 [f2fs] [<ffffffffa02a6ca2>] f2fs_getxattr+0x52/0xe0 [f2fs] [<ffffffffa02a7481>] f2fs_get_acl+0x41/0x2d0 [f2fs] [<ffffffff8122d847>] get_acl+0x47/0x70 [<ffffffff8122db5a>] posix_acl_create+0x5a/0x150 [<ffffffffa02a7759>] f2fs_init_acl+0x29/0xcb [f2fs] [<ffffffffa0286a8d>] init_inode_metadata+0x5d/0x340 [f2fs] [<ffffffffa029253a>] f2fs_add_inline_entry+0x12a/0x2e0 [f2fs] [<ffffffffa0286ea5>] __f2fs_add_link+0x45/0x4a0 [f2fs] [<ffffffffa028b5b6>] ? f2fs_new_inode+0x146/0x220 [f2fs] [<ffffffffa028b816>] f2fs_mknod+0x86/0xf0 [f2fs] [<ffffffff811e3ec1>] vfs_mknod+0xe1/0x160 [<ffffffff811e4b26>] SyS_mknod+0x1f6/0x200 [<ffffffff81741d7f>] tracesys+0xe1/0xe6 Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-10-14 02:42:53 +00:00
const char *name, void *buffer,
size_t buffer_size, struct page *dpage)
{
return -EOPNOTSUPP;
}
static inline ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer,
size_t buffer_size)
{
return -EOPNOTSUPP;
}
#endif
#ifdef CONFIG_F2FS_FS_SECURITY
extern int f2fs_init_security(struct inode *, struct inode *,
const struct qstr *, struct page *);
#else
static inline int f2fs_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, struct page *ipage)
{
return 0;
}
#endif
#endif /* __F2FS_XATTR_H__ */