linux-stable/fs/ocfs2/aops.h
Dmitry Antipov adc77b19f6 ocfs2: fix uninitialized value in ocfs2_file_read_iter()
Syzbot has reported the following KMSAN splat:

BUG: KMSAN: uninit-value in ocfs2_file_read_iter+0x9a4/0xf80
 ocfs2_file_read_iter+0x9a4/0xf80
 __io_read+0x8d4/0x20f0
 io_read+0x3e/0xf0
 io_issue_sqe+0x42b/0x22c0
 io_wq_submit_work+0xaf9/0xdc0
 io_worker_handle_work+0xd13/0x2110
 io_wq_worker+0x447/0x1410
 ret_from_fork+0x6f/0x90
 ret_from_fork_asm+0x1a/0x30

Uninit was created at:
 __alloc_pages_noprof+0x9a7/0xe00
 alloc_pages_mpol_noprof+0x299/0x990
 alloc_pages_noprof+0x1bf/0x1e0
 allocate_slab+0x33a/0x1250
 ___slab_alloc+0x12ef/0x35e0
 kmem_cache_alloc_bulk_noprof+0x486/0x1330
 __io_alloc_req_refill+0x84/0x560
 io_submit_sqes+0x172f/0x2f30
 __se_sys_io_uring_enter+0x406/0x41c0
 __x64_sys_io_uring_enter+0x11f/0x1a0
 x64_sys_call+0x2b54/0x3ba0
 do_syscall_64+0xcd/0x1e0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Since an instance of 'struct kiocb' may be passed from the block layer
with 'private' field uninitialized, introduce 'ocfs2_iocb_init_rw_locked()'
and use it from where 'ocfs2_dio_end_io()' might take care, i.e. in
'ocfs2_file_read_iter()' and 'ocfs2_file_write_iter()'.

Link: https://lkml.kernel.org/r/20241029091736.1501946-1-dmantipov@yandex.ru
Fixes: 7cdfc3a1c3 ("ocfs2: Remember rw lock level during direct io")
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reported-by: syzbot+a73e253cca4f0230a5a5@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a73e253cca4f0230a5a5
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-11-11 17:17:04 -08:00

81 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2002, 2004, 2005 Oracle. All rights reserved.
*/
#ifndef OCFS2_AOPS_H
#define OCFS2_AOPS_H
#include <linux/fs.h>
handle_t *ocfs2_start_walk_page_trans(struct inode *inode,
struct page *page,
unsigned from,
unsigned to);
int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
struct inode *inode, unsigned int from,
unsigned int to, int new);
void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages);
int walk_page_buffers( handle_t *handle,
struct buffer_head *head,
unsigned from,
unsigned to,
int *partial,
int (*fn)( handle_t *handle,
struct buffer_head *bh));
int ocfs2_write_end_nolock(struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied, void *fsdata);
typedef enum {
OCFS2_WRITE_BUFFER = 0,
OCFS2_WRITE_DIRECT,
OCFS2_WRITE_MMAP,
} ocfs2_write_type_t;
int ocfs2_write_begin_nolock(struct address_space *mapping,
loff_t pos, unsigned len, ocfs2_write_type_t type,
struct folio **foliop, void **fsdata,
struct buffer_head *di_bh, struct page *mmap_page);
int ocfs2_read_inline_data(struct inode *inode, struct page *page,
struct buffer_head *di_bh);
int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size);
int ocfs2_get_block(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create);
/* all ocfs2_dio_end_io()'s fault */
#define ocfs2_iocb_is_rw_locked(iocb) \
test_bit(0, (unsigned long *)&iocb->private)
static inline void ocfs2_iocb_set_rw_locked(struct kiocb *iocb, int level)
{
set_bit(0, (unsigned long *)&iocb->private);
if (level)
set_bit(1, (unsigned long *)&iocb->private);
else
clear_bit(1, (unsigned long *)&iocb->private);
}
/*
* Using a named enum representing lock types in terms of #N bit stored in
* iocb->private, which is going to be used for communication between
* ocfs2_dio_end_io() and ocfs2_file_write/read_iter().
*/
enum ocfs2_iocb_lock_bits {
OCFS2_IOCB_RW_LOCK = 0,
OCFS2_IOCB_RW_LOCK_LEVEL,
OCFS2_IOCB_NUM_LOCKS
};
#define ocfs2_iocb_init_rw_locked(iocb) \
(iocb->private = NULL)
#define ocfs2_iocb_clear_rw_locked(iocb) \
clear_bit(OCFS2_IOCB_RW_LOCK, (unsigned long *)&iocb->private)
#define ocfs2_iocb_rw_locked_level(iocb) \
test_bit(OCFS2_IOCB_RW_LOCK_LEVEL, (unsigned long *)&iocb->private)
#endif /* OCFS2_FILE_H */