From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4B5C61170E for ; Mon, 11 Sep 2023 14:18:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C462CC433C8; Mon, 11 Sep 2023 14:17:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694441880; bh=udAOpIMbBqyBv7kg1qssYjbpDgJnxBgsbkcO5ERcvM0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AwPWDhUkbSK9zmNo+omcix+d7cf2cxstjLQiSoILzmuIeb3Dj5XA4T0D/B5u506PS 0/IUX9S0Pwo7SJqVLme3DEph3X8Ex1Zudi1vuYOYlMAG49lmzvvgalzeU9SWoXV/jK +yD/B4z8JF+mdCEKAUGmDzKjVXqNoiX2PCa4m21U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 6.5 551/739] f2fs: fix to avoid mmap vs set_compress_option case Date: Mon, 11 Sep 2023 15:45:50 +0200 Message-ID: <20230911134706.480188958@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230911134650.921299741@linuxfoundation.org> References: <20230911134650.921299741@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chao Yu [ Upstream commit b5ab3276eb69cacf44ecfb11b2bfab73096ff4e4 ] Compression option in inode should not be changed after they have been used, however, it may happen in below race case: Thread A Thread B - f2fs_ioc_set_compress_option - check f2fs_is_mmap_file() - check get_dirty_pages() - check F2FS_HAS_BLOCKS() - f2fs_file_mmap - set_inode_flag(FI_MMAP_FILE) - fault - do_page_mkwrite - f2fs_vm_page_mkwrite - f2fs_get_block_locked - fault_dirty_shared_page - set_page_dirty - update i_compress_algorithm - update i_log_cluster_size - update i_cluster_size Avoid such race condition by covering f2fs_file_mmap() w/ i_sem lock, meanwhile add mmap file check condition in f2fs_may_compress() as well. Fixes: e1e8debec656 ("f2fs: add F2FS_IOC_SET_COMPRESS_OPTION ioctl") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/f2fs.h | 3 ++- fs/f2fs/file.c | 23 ++++++++++++++++++----- 2 files changed, 20 insertions(+), 6 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index c7cb2177b2527..d372bedb0fe4e 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -4483,7 +4483,8 @@ static inline bool f2fs_low_mem_mode(struct f2fs_sb_info *sbi) static inline bool f2fs_may_compress(struct inode *inode) { if (IS_SWAPFILE(inode) || f2fs_is_pinned_file(inode) || - f2fs_is_atomic_file(inode) || f2fs_has_inline_data(inode)) + f2fs_is_atomic_file(inode) || f2fs_has_inline_data(inode) || + f2fs_is_mmap_file(inode)) return false; return S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode); } diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 093039dee9920..d9073afe021fd 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -526,7 +526,11 @@ static int f2fs_file_mmap(struct file *file, struct vm_area_struct *vma) file_accessed(file); vma->vm_ops = &f2fs_file_vm_ops; + + f2fs_down_read(&F2FS_I(inode)->i_sem); set_inode_flag(inode, FI_MMAP_FILE); + f2fs_up_read(&F2FS_I(inode)->i_sem); + return 0; } @@ -1919,12 +1923,19 @@ static int f2fs_setflags_common(struct inode *inode, u32 iflags, u32 mask) int err = f2fs_convert_inline_inode(inode); if (err) return err; - if (!f2fs_may_compress(inode)) - return -EINVAL; - if (S_ISREG(inode->i_mode) && F2FS_HAS_BLOCKS(inode)) + + f2fs_down_write(&F2FS_I(inode)->i_sem); + if (!f2fs_may_compress(inode) || + (S_ISREG(inode->i_mode) && + F2FS_HAS_BLOCKS(inode))) { + f2fs_up_write(&F2FS_I(inode)->i_sem); return -EINVAL; - if (set_compress_context(inode)) - return -EOPNOTSUPP; + } + err = set_compress_context(inode); + f2fs_up_write(&F2FS_I(inode)->i_sem); + + if (err) + return err; } } @@ -3976,6 +3987,7 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg) file_start_write(filp); inode_lock(inode); + f2fs_down_write(&F2FS_I(inode)->i_sem); if (f2fs_is_mmap_file(inode) || get_dirty_pages(inode)) { ret = -EBUSY; goto out; @@ -3995,6 +4007,7 @@ static int f2fs_ioc_set_compress_option(struct file *filp, unsigned long arg) f2fs_warn(sbi, "compression algorithm is successfully set, " "but current kernel doesn't support this algorithm."); out: + f2fs_up_write(&F2FS_I(inode)->i_sem); inode_unlock(inode); file_end_write(filp); -- 2.40.1