On Mon, May 28, 2018 at 11:37 PM, Nick Desaulniers
<nick.desaulni...@gmail.com> wrote:
> Fixes a stringop-truncation warning from gcc-8.
>
> Signed-off-by: Nick Desaulniers <nick.desaulni...@gmail.com>
> ---
> include/trace/events/writeback.h | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/include/trace/events/writeback.h
> b/include/trace/events/writeback.h
> index 32db72c..cfaf57d 100644
> --- a/include/trace/events/writeback.h
> +++ b/include/trace/events/writeback.h
> @@ -66,7 +66,7 @@ TRACE_EVENT(writeback_dirty_page,
> ),
>
> TP_fast_assign(
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> mapping ? dev_name(inode_to_bdi(mapping->host)->dev)
> : "(unknown)", 32);
> __entry->ino = mapping ? mapping->host->i_ino : 0;
> __entry->index = page->index;
> @@ -96,7 +96,7 @@ DECLARE_EVENT_CLASS(writeback_dirty_inode_template,
> struct backing_dev_info *bdi = inode_to_bdi(inode);
>
> /* may be called for files on pseudo FSes w/ unregistered bdi
> */
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> bdi->dev ? dev_name(bdi->dev) : "(unknown)", 32);
> __entry->ino = inode->i_ino;
> __entry->state = inode->i_state;
> @@ -176,7 +176,7 @@ DECLARE_EVENT_CLASS(writeback_write_inode_template,
> ),
>
> TP_fast_assign(
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> dev_name(inode_to_bdi(inode)->dev), 32);
> __entry->ino = inode->i_ino;
> __entry->sync_mode = wbc->sync_mode;
> @@ -220,7 +220,7 @@ DECLARE_EVENT_CLASS(writeback_work_class,
> __field(unsigned int, cgroup_ino)
> ),
> TP_fast_assign(
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> wb->bdi->dev ? dev_name(wb->bdi->dev) : "(unknown)",
> 32);
> __entry->nr_pages = work->nr_pages;
> __entry->sb_dev = work->sb ? work->sb->s_dev : 0;
> @@ -274,7 +274,7 @@ DECLARE_EVENT_CLASS(writeback_class,
> __field(unsigned int, cgroup_ino)
> ),
> TP_fast_assign(
> - strncpy(__entry->name, dev_name(wb->bdi->dev), 32);
> + strlcpy(__entry->name, dev_name(wb->bdi->dev), 32);
> __entry->cgroup_ino = __trace_wb_assign_cgroup(wb);
> ),
> TP_printk("bdi %s: cgroup_ino=%u",
> @@ -296,7 +296,7 @@ TRACE_EVENT(writeback_bdi_register,
> __array(char, name, 32)
> ),
> TP_fast_assign(
> - strncpy(__entry->name, dev_name(bdi->dev), 32);
> + strlcpy(__entry->name, dev_name(bdi->dev), 32);
> ),
> TP_printk("bdi %s",
> __entry->name
> @@ -321,7 +321,7 @@ DECLARE_EVENT_CLASS(wbc_class,
> ),
>
> TP_fast_assign(
> - strncpy(__entry->name, dev_name(bdi->dev), 32);
> + strlcpy(__entry->name, dev_name(bdi->dev), 32);
> __entry->nr_to_write = wbc->nr_to_write;
> __entry->pages_skipped = wbc->pages_skipped;
> __entry->sync_mode = wbc->sync_mode;
> @@ -372,7 +372,7 @@ TRACE_EVENT(writeback_queue_io,
> ),
> TP_fast_assign(
> unsigned long *older_than_this = work->older_than_this;
> - strncpy(__entry->name, dev_name(wb->bdi->dev), 32);
> + strlcpy(__entry->name, dev_name(wb->bdi->dev), 32);
> __entry->older = older_than_this ? *older_than_this : 0;
> __entry->age = older_than_this ?
> (jiffies - *older_than_this) * 1000 / HZ :
> -1;
> @@ -583,7 +583,7 @@ TRACE_EVENT(writeback_sb_inodes_requeue,
> ),
>
> TP_fast_assign(
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> dev_name(inode_to_bdi(inode)->dev), 32);
> __entry->ino = inode->i_ino;
> __entry->state = inode->i_state;
> @@ -657,7 +657,7 @@ DECLARE_EVENT_CLASS(writeback_single_inode_template,
> ),
>
> TP_fast_assign(
> - strncpy(__entry->name,
> + strlcpy(__entry->name,
> dev_name(inode_to_bdi(inode)->dev), 32);
> __entry->ino = inode->i_ino;
> __entry->state = inode->i_state;
> --
> 2.7.4
>
Eric points out this wont initialize the rest of the dest if src if
less than size.
