korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-16 08:44:21 +08:00
Code Issues Packages Projects Releases Wiki Activity

fs/ntfs3: don't hold ni_lock when calling truncate_setsize()

Browse Source 
[ Upstream commit 0226635c30 ]

syzbot is reporting hung task at do_user_addr_fault() [1], for there is
a silent deadlock between PG_locked bit and ni_lock lock.

Since filemap_update_page() calls filemap_read_folio() after calling
folio_trylock() which will set PG_locked bit, ntfs_truncate() must not
call truncate_setsize() which will wait for PG_locked bit to be cleared
when holding ni_lock lock.

Link: https://lore.kernel.org/all/00000000000060d41f05f139aa44@google.com/
Link: https://syzkaller.appspot.com/bug?extid=bed15dbf10294aa4f2ae [1]
Reported-by: syzbot <syzbot+bed15dbf10294aa4f2ae@syzkaller.appspotmail.com>
Debugged-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-developed-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 4342306f0f ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Tetsuo Handa 2023-01-02 23:05:33 +09:00 committed by Greg Kroah-Hartman
parent a23e8376e6
commit 8414983c2e
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/ntfs3/file.c
View File

@ -488,10 +488,10 @@ static int ntfs_truncate(struct inode *inode, loff_t new_size)
new_valid = ntfs_up_block(sb, min_t(u64, ni->i_valid, new_size));
ni_lock(ni);
truncate_setsize(inode, new_size);
ni_lock(ni);
down_write(&ni->file.run_lock);
err = attr_set_size(ni, ATTR_DATA, NULL, 0, &ni->file.run, new_size,
&new_valid, ni->mi.sbi->options->prealloc, NULL);