From 894c6350eaad7e613ae267504014a456e00a3e2a Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Thu, 29 Jan 2015 02:50:33 +0000 Subject: splice: Apply generic position and size checks to each write We need to check the position and size of file writes against various limits, using generic_write_check(). This was not being done for the splice write path. It was fixed upstream by commit 8d0207652cbe ("->splice_write() via ->write_iter()") but we can't apply that. CVE-2014-7822 Signed-off-by: Ben Hutchings --- fs/ocfs2/file.c | 8 ++++++-- fs/splice.c | 8 ++++++-- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index d20d64c..0de24a2 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2468,9 +2468,7 @@ static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe, struct address_space *mapping = out->f_mapping; struct inode *inode = mapping->host; struct splice_desc sd = { - .total_len = len, .flags = flags, - .pos = *ppos, .u.file = out, }; @@ -2480,6 +2478,12 @@ static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe, out->f_path.dentry->d_name.len, out->f_path.dentry->d_name.name, len); + ret = generic_write_checks(out, ppos, &len, 0); + if (ret) + return ret; + sd.total_len = len; + sd.pos = *ppos; + if (pipe->inode) mutex_lock_nested(&pipe->inode->i_mutex, I_MUTEX_PARENT); diff --git a/fs/splice.c b/fs/splice.c index 714471d..34c2b2b 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -1013,13 +1013,17 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out, struct address_space *mapping = out->f_mapping; struct inode *inode = mapping->host; struct splice_desc sd = { - .total_len = len, .flags = flags, - .pos = *ppos, .u.file = out, }; ssize_t ret; + ret = generic_write_checks(out, ppos, &len, S_ISBLK(inode->i_mode)); + if (ret) + return ret; + sd.total_len = len; + sd.pos = *ppos; + pipe_lock(pipe); splice_from_pipe_begin(&sd); -- cgit v1.1