From 209bd086e423d98ddf2fd52a6f1afda15b5758b1 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 7 Jan 2014 12:58:19 -0500 Subject: [PATCH] ext4: avoid clearing beyond i_blocks when truncating an inline data file commit 09c455aaa8f47a94d5bafaa23d58365768210507 upstream. A missing cast means that when we are truncating a file which is less than 60 bytes, we don't clear the correct area of memory, and in fact we can end up truncating the next inode in the inode table, or worse yet, some other kernel data structure. Addresses-Coverity-Id: #751987 Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- fs/ext4/inline.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index 33331b4..e350be6 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -1957,9 +1957,11 @@ void ext4_inline_data_truncate(struct inode *inode, int *has_inline) } /* Clear the content within i_blocks. */ - if (i_size < EXT4_MIN_INLINE_DATA_SIZE) - memset(ext4_raw_inode(&is.iloc)->i_block + i_size, 0, - EXT4_MIN_INLINE_DATA_SIZE - i_size); + if (i_size < EXT4_MIN_INLINE_DATA_SIZE) { + void *p = (void *) ext4_raw_inode(&is.iloc)->i_block; + memset(p + i_size, 0, + EXT4_MIN_INLINE_DATA_SIZE - i_size); + } EXT4_I(inode)->i_inline_size = i_size < EXT4_MIN_INLINE_DATA_SIZE ? -- 2.7.4