From: Hui Su sh_def@163.com
commit fdeb17c70c9ecae655378761accf5a26a55a33cf upstream.
The bdi_dev_name() returns a char [64], and the __entry->name is a char [32].
It maybe dangerous to TP_printk("%s", __entry->name) after the strncpy().
CC: stable@vger.kernel.org Link: https://lore.kernel.org/r/20201124165205.GA23937@rlk Acked-by: Steven Rostedt (VMware) rostedt@goodmis.org Acked-by: Tejun Heo tj@kernel.org Signed-off-by: Hui Su sh_def@163.com Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/trace/events/writeback.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -192,7 +192,7 @@ TRACE_EVENT(inode_foreign_history, ),
TP_fast_assign( - strncpy(__entry->name, bdi_dev_name(inode_to_bdi(inode)), 32); + strscpy_pad(__entry->name, bdi_dev_name(inode_to_bdi(inode)), 32); __entry->ino = inode->i_ino; __entry->cgroup_ino = __trace_wbc_assign_cgroup(wbc); __entry->history = history; @@ -221,7 +221,7 @@ TRACE_EVENT(inode_switch_wbs, ),
TP_fast_assign( - strncpy(__entry->name, bdi_dev_name(old_wb->bdi), 32); + strscpy_pad(__entry->name, bdi_dev_name(old_wb->bdi), 32); __entry->ino = inode->i_ino; __entry->old_cgroup_ino = __trace_wb_assign_cgroup(old_wb); __entry->new_cgroup_ino = __trace_wb_assign_cgroup(new_wb); @@ -254,7 +254,7 @@ TRACE_EVENT(track_foreign_dirty, struct address_space *mapping = page_mapping(page); struct inode *inode = mapping ? mapping->host : NULL;
- strncpy(__entry->name, bdi_dev_name(wb->bdi), 32); + strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32); __entry->bdi_id = wb->bdi->id; __entry->ino = inode ? inode->i_ino : 0; __entry->memcg_id = wb->memcg_css->id; @@ -287,7 +287,7 @@ TRACE_EVENT(flush_foreign, ),
TP_fast_assign( - strncpy(__entry->name, bdi_dev_name(wb->bdi), 32); + strscpy_pad(__entry->name, bdi_dev_name(wb->bdi), 32); __entry->cgroup_ino = __trace_wb_assign_cgroup(wb); __entry->frn_bdi_id = frn_bdi_id; __entry->frn_memcg_id = frn_memcg_id;