Messages in this thread Patch in this message | | | From | Jaewook Kim <> | Subject | [PATCH] f2fs: do not allow to decompress files have FI_COMPRESS_RELEASED | Date | Wed, 3 Aug 2022 11:34:31 +0900 |
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If a file has FI_COMPRESS_RELEASED, all writes for it should not be allowed. However, as of now, in case of compress_mode=user, writes triggered by IOCTLs like F2FS_IOC_DE/COMPRESS_FILE are allowed unexpectly, which could crash that file. To fix it, let's do not allow F2FS_IOC_DE/COMPRESS_IOCTL if a file already has FI_COMPRESS_RELEASED flag.
This is the reproduction process: 1. $ chattr +c ./file 2. $ dd if=/dev/zero of=./file bs=4096 count=2000 oflag=append conv=notrunc 3. $ sync 4. $ do_compress ./file ; call F2FS_IOC_COMPRESS_FILE 5. $ get_compr_blocks ./file ; call F2FS_IOC_GET_COMPRESS_BLOCKS 6. $ do_compress ./file ; call F2FS_IOC_COMPRESS_FILE again 7. $ get_compr_blocks ./file ; call F2FS_IOC_GET_COMPRESS_BLOCKS again
You can find compr_blocks has a negative value.
Fixes: 5fdb322ff2c2b ("f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE")
Signed-off-by: Junbeom Yeom <junbeom.yeom@samsung.com> Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com> Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com> Signed-off-by: Jaewook Kim <jw5454.kim@samsung.com> --- fs/f2fs/file.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 6b1b030830ca..a4713b7e12cb 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -3945,6 +3945,11 @@ static int f2fs_ioc_decompress_file(struct file *filp, unsigned long arg) goto out; } + if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) { + ret = -EINVAL; + goto out; + } + ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX); if (ret) goto out; @@ -4012,6 +4017,11 @@ static int f2fs_ioc_compress_file(struct file *filp, unsigned long arg) goto out; } + if (is_inode_flag_set(inode, FI_COMPRESS_RELEASED)) { + ret = -EINVAL; + goto out; + } + ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX); if (ret) goto out; -- 2.17.1
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