diff options
| author | Tetsuo Handa | 2023-01-02 23:05:33 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-01-12 12:02:28 +0100 |
| commit | 73fee7e1e5ea11b51c51c46e0577a197ca3602cf (patch) | |
| tree | 4272f79c777c7e3b93ca7a360c71e2c9a932602c /fs/ntfs3 | |
| parent | 71f9fd5bcf0954377eec3dc1119c44064f10679b (diff) | |
fs/ntfs3: don't hold ni_lock when calling truncate_setsize()
[ Upstream commit 0226635c304cfd5c9db9b78c259cb713819b057e ]
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: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/ntfs3')
| -rw-r--r-- | fs/ntfs3/file.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c index 4f2ffc7ef296..f31c0389a2e7 100644 --- a/fs/ntfs3/file.c +++ b/fs/ntfs3/file.c @@ -486,10 +486,10 @@ 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); |