chenyuwen reports a f2fs bug as below:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000011
fscrypt_set_bio_crypt_ctx+0x78/0x1e8
f2fs_grab_read_bio+0x78/0x208
f2fs_submit_page_read+0x44/0x154
f2fs_get_read_data_page+0x288/0x5f4
f2fs_get_lock_data_page+0x60/0x190
truncate_partial_data_page+0x108/0x4fc
f2fs_do_truncate_blocks+0x344/0x5f0
f2fs_truncate_blocks+0x6c/0x134
f2fs_truncate+0xd8/0x200
f2fs_iget+0x20c/0x5ac
do_garbage_collect+0x5d0/0xf6c
f2fs_gc+0x22c/0x6a4
f2fs_disable_checkpoint+0xc8/0x310
f2fs_fill_super+0x14bc/0x1764
mount_bdev+0x1b4/0x21c
f2fs_mount+0x20/0x30
legacy_get_tree+0x50/0xbc
vfs_get_tree+0x5c/0x1b0
do_new_mount+0x298/0x4cc
path_mount+0x33c/0x5fc
__arm64_sys_mount+0xcc/0x15c
invoke_syscall+0x60/0x150
el0_svc_common+0xb8/0xf8
do_el0_svc+0x28/0xa0
el0_svc+0x24/0x84
el0t_64_sync_handler+0x88/0xec
It is because inode.i_crypt_info is not initialized during below path:
- mount
- f2fs_fill_super
- f2fs_disable_checkpoint
- f2fs_gc
- f2fs_iget
- f2fs_truncate
So, let's relocate truncation of preallocated blocks to f2fs_file_open(),
after fscrypt_file_open().
Fixes: d4dd19ec1ea0 ("f2fs: do not expose unwritten blocks to user by DIO")
Reported-by: chenyuwen <[email protected]>
Closes: https://lore.kernel.org/linux-kernel/[email protected]
Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/file.c | 28 +++++++++++++++++++++++++++-
fs/f2fs/inode.c | 8 --------
2 files changed, 27 insertions(+), 9 deletions(-)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index ef4cfb4436ef..058fcc83a2fc 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -554,6 +554,28 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma)
return 0;
}
+static int finish_preallocate_blocks(struct inode *inode)
+{
+ int ret;
+
+ if (is_sbi_flag_set(F2FS_I_SB(inode), SBI_POR_DOING))
+ return 0;
+
+ inode_lock(inode);
+ if (!file_should_truncate(inode)) {
+ inode_unlock(inode);
+ return 0;
+ }
+
+ ret = f2fs_truncate(inode);
+ inode_unlock(inode);
+ if (ret)
+ return ret;
+
+ file_dont_truncate(inode);
+ return 0;
+}
+
static int f2fs_file_open(struct inode *inode, struct file *filp)
{
int err = fscrypt_file_open(inode, filp);
@@ -571,7 +593,11 @@ static int f2fs_file_open(struct inode *inode, struct file *filp)
filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
filp->f_mode |= FMODE_CAN_ODIRECT;
- return dquot_file_open(inode, filp);
+ err = dquot_file_open(inode, filp);
+ if (err)
+ return err;
+
+ return finish_preallocate_blocks(inode);
}
void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count)
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 005dde72aff3..791c06e159fd 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -610,14 +610,6 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino)
}
f2fs_set_inode_flags(inode);
- if (file_should_truncate(inode) &&
- !is_sbi_flag_set(sbi, SBI_POR_DOING)) {
- ret = f2fs_truncate(inode);
- if (ret)
- goto bad_inode;
- file_dont_truncate(inode);
- }
-
unlock_new_inode(inode);
trace_f2fs_iget(inode);
return inode;
--
2.40.1