From 09c455aaa8f47a94d5bafaa23d58365768210507 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 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" Cc: stable@vger.kernel.org --- 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 c417e52d194e..ed29e720e880 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -1928,9 +1928,11 @@ 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 ? -- 2.34.1