Fix: writeback: out-of-bound reads

Use ctf_string rather than ctf_array_text for name fields, because the
source strings are not guaranteed to be at least 32 bytes.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/instrumentation/events/lttng-module/writeback.h b/instrumentation/events/lttng-module/writeback.h
index 5e4d0474109cb98bd78e1e030688ba7e34e36db2..4baa85a911aeecec64827f92db27f5ec5b2e30de 100644 (file)
--- a/instrumentation/events/lttng-module/writeback.h
+++ b/instrumentation/events/lttng-module/writeback.h
@@ -96,8 +96,8 @@ LTTNG_TRACEPOINT_EVENT(writeback_dirty_page,
        TP_PROTO(struct page *page, struct address_space *mapping),
        TP_ARGS(page, mapping),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       mapping ? dev_name(lttng_inode_to_bdi(mapping->host)->dev) : "(unknown)", 32)
+               ctf_string(name,
+                       mapping ? dev_name(lttng_inode_to_bdi(mapping->host)->dev) : "(unknown)")
                ctf_integer(unsigned long, ino, mapping ? mapping->host->i_ino : 0)
                ctf_integer(pgoff_t, index, page->index)
        )
@@ -108,9 +108,9 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_dirty_inode_template,
        TP_ARGS(inode, flags),
        TP_FIELDS(
                /* may be called for files on pseudo FSes w/ unregistered bdi */
-               ctf_array_text(char, name,
+               ctf_string(name,
                        lttng_inode_to_bdi(inode)->dev ?
-                               dev_name(lttng_inode_to_bdi(inode)->dev) : "(unknown)", 32)
+                               dev_name(lttng_inode_to_bdi(inode)->dev) : "(unknown)")
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(unsigned long, state, inode->i_state)
                ctf_integer(unsigned long, flags, flags)
@@ -128,8 +128,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_write_inode_template,
        TP_PROTO(struct inode *inode, struct writeback_control *wbc),
        TP_ARGS(inode, wbc),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(lttng_inode_to_bdi(inode)->dev), 32)
+               ctf_string(name,
+                       dev_name(lttng_inode_to_bdi(inode)->dev))
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(int, sync_mode, wbc->sync_mode)
        )
@@ -148,8 +148,8 @@ LTTNG_TRACEPOINT_EVENT(writeback_dirty_page,
        TP_PROTO(struct page *page, struct address_space *mapping),
        TP_ARGS(page, mapping),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       mapping ? dev_name(mapping->backing_dev_info->dev) : "(unknown)", 32)
+               ctf_string(name,
+                       mapping ? dev_name(mapping->backing_dev_info->dev) : "(unknown)")
                ctf_integer(unsigned long, ino, mapping ? mapping->host->i_ino : 0)
                ctf_integer(pgoff_t, index, page->index)
        )
@@ -160,10 +160,10 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_dirty_inode_template,
        TP_ARGS(inode, flags),
        TP_FIELDS(
                /* may be called for files on pseudo FSes w/ unregistered bdi */
-               ctf_array_text(char, name,
+               ctf_string(name,
                        inode->i_mapping->backing_dev_info->dev ?
                                dev_name(inode->i_mapping->backing_dev_info->dev)
-                               : "(unknown)", 32)
+                               : "(unknown)")
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(unsigned long, flags, flags)
        )
@@ -179,8 +179,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_write_inode_template,
        TP_PROTO(struct inode *inode, struct writeback_control *wbc),
        TP_ARGS(inode, wbc),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(inode->i_mapping->backing_dev_info->dev), 32)
+               ctf_string(name,
+                       dev_name(inode->i_mapping->backing_dev_info->dev))
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(int, sync_mode, wbc->sync_mode)
        )
@@ -201,8 +201,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
        TP_PROTO(struct bdi_writeback *wb, struct wb_writeback_work *work),
        TP_ARGS(wb, work),
        TP_FIELDS(
-               ctf_array_text(char, name, wb->bdi->dev ? dev_name(wb->bdi->dev) :
-                               "(unknown)", 32)
+               ctf_string(name, wb->bdi->dev ? dev_name(wb->bdi->dev) :
+                               "(unknown)")
        )
 )
 
@@ -212,8 +212,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
        TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work),
        TP_ARGS(bdi, work),
        TP_FIELDS(
-               ctf_array_text(char, name, bdi->dev ? dev_name(bdi->dev) :
-                               "(unknown)", 32)
+               ctf_string(name, bdi->dev ? dev_name(bdi->dev) :
+                               "(unknown)")
        )
 )
 
@@ -223,9 +223,9 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_work_class,
        TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work),
        TP_ARGS(bdi, work),
        TP_FIELDS(
-               ctf_array_text(char, name,
+               ctf_string(name,
                        dev_name(bdi->dev ? bdi->dev :
-                               default_backing_dev_info.dev), 32)
+                               default_backing_dev_info.dev))
        )
 )
 
@@ -270,8 +270,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_class,
        TP_PROTO(struct bdi_writeback *wb),
        TP_ARGS(wb),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(wb->bdi->dev), 32)
+               ctf_string(name,
+                       dev_name(wb->bdi->dev))
        )
 )
 
@@ -290,8 +290,8 @@ LTTNG_TRACEPOINT_EVENT(writeback_bdi_register,
        TP_PROTO(struct backing_dev_info *bdi),
        TP_ARGS(bdi),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(bdi->dev), 32)
+               ctf_string(name,
+                       dev_name(bdi->dev))
        )
 )
 
@@ -301,8 +301,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_class,
        TP_PROTO(struct backing_dev_info *bdi),
        TP_ARGS(bdi),
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(bdi->dev), 32)
+               ctf_string(name,
+                       dev_name(bdi->dev))
        )
 )
 
@@ -341,7 +341,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(balance_dirty_written,
        TP_ARGS(bdi, written),
 
        TP_FIELDS(
-               ctf_array_text(char, name, dev_name(bdi->dev), 32)
+               ctf_string(name, dev_name(bdi->dev))
                ctf_integer(int, written, written)
        )
 )
@@ -351,7 +351,7 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_wbc_class,
        TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi),
        TP_ARGS(wbc, bdi),
        TP_FIELDS(
-               ctf_array_text(char, name, dev_name(bdi->dev), 32)
+               ctf_string(name, dev_name(bdi->dev))
                ctf_integer(long, nr_to_write, wbc->nr_to_write)
                ctf_integer(long, pages_skipped, wbc->pages_skipped)
                ctf_integer(int, sync_mode, wbc->sync_mode)
@@ -399,7 +399,7 @@ LTTNG_TRACEPOINT_EVENT(writeback_queue_io,
                 int moved),
        TP_ARGS(wb, work, dirtied_before, moved),
        TP_FIELDS(
-               ctf_array_text(char, name, dev_name(wb->bdi->dev), 32)
+               ctf_string(name, dev_name(wb->bdi->dev))
                ctf_integer(unsigned long, older, dirtied_before)
                ctf_integer(int, moved, moved)
        )
@@ -411,7 +411,7 @@ LTTNG_TRACEPOINT_EVENT(writeback_queue_io,
                 int moved),
        TP_ARGS(wb, work, moved),
        TP_FIELDS(
-               ctf_array_text(char, name, dev_name(wb->bdi->dev), 32)
+               ctf_string(name, dev_name(wb->bdi->dev))
                ctf_integer(int, moved, moved)
        )
 )
@@ -422,7 +422,7 @@ LTTNG_TRACEPOINT_EVENT(writeback_queue_io,
                 int moved),
        TP_ARGS(wb, older_than_this, moved),
        TP_FIELDS(
-               ctf_array_text(char, name, dev_name(wb->bdi->dev), 32)
+               ctf_string(name, dev_name(wb->bdi->dev))
                ctf_integer(unsigned long, older,
                        older_than_this ? *older_than_this : 0)
                ctf_integer(long, age,
@@ -524,7 +524,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(bdi_dirty_ratelimit,
        TP_ARGS(wb, dirty_rate, task_ratelimit),
 
        TP_FIELDS(
-               ctf_array_text(char, bdi, dev_name(wb->bdi->dev), 32)
+               ctf_string(bdi, dev_name(wb->bdi->dev))
                ctf_integer(unsigned long, write_bw, KBps(wb->bdi->wb.write_bandwidth))
                ctf_integer(unsigned long, avg_write_bw, KBps(wb->bdi->wb.avg_write_bandwidth))
                ctf_integer(unsigned long, dirty_rate, KBps(dirty_rate))
@@ -548,7 +548,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(bdi_dirty_ratelimit,
        TP_ARGS(bdi, dirty_rate, task_ratelimit),
 
        TP_FIELDS(
-               ctf_array_text(char, bdi, dev_name(bdi->dev), 32)
+               ctf_string(bdi, dev_name(bdi->dev))
                ctf_integer(unsigned long, write_bw, KBps(bdi->wb.write_bandwidth))
                ctf_integer(unsigned long, avg_write_bw, KBps(bdi->wb.avg_write_bandwidth))
                ctf_integer(unsigned long, dirty_rate, KBps(dirty_rate))
@@ -572,7 +572,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(bdi_dirty_ratelimit,
        TP_ARGS(bdi, dirty_rate, task_ratelimit),
 
        TP_FIELDS(
-               ctf_array_text(char, bdi, dev_name(bdi->dev), 32)
+               ctf_string(bdi, dev_name(bdi->dev))
                ctf_integer(unsigned long, write_bw, KBps(bdi->write_bandwidth))
                ctf_integer(unsigned long, avg_write_bw, KBps(bdi->avg_write_bandwidth))
                ctf_integer(unsigned long, dirty_rate, KBps(dirty_rate))
@@ -610,7 +610,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(balance_dirty_pages,
        ),
 
        TP_FIELDS(
-               ctf_array_text(char, bdi, dev_name(wb->bdi->dev), 32)
+               ctf_string(bdi, dev_name(wb->bdi->dev))
                ctf_integer(unsigned long, limit, global_dirty_limit)
                ctf_integer(unsigned long, setpoint,
                        (global_dirty_limit + (thresh + bg_thresh) / 2) / 2)
@@ -668,7 +668,7 @@ LTTNG_TRACEPOINT_EVENT_MAP(balance_dirty_pages,
        ),
 
        TP_FIELDS(
-               ctf_array_text(char, bdi, dev_name(bdi->dev), 32)
+               ctf_string(bdi, dev_name(bdi->dev))
                ctf_integer(unsigned long, limit, global_dirty_limit)
                ctf_integer(unsigned long, setpoint,
                        (global_dirty_limit + (thresh + bg_thresh) / 2) / 2)
@@ -707,8 +707,8 @@ LTTNG_TRACEPOINT_EVENT(writeback_sb_inodes_requeue,
        TP_ARGS(inode),
 
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(lttng_inode_to_bdi(inode)->dev), 32)
+               ctf_string(name,
+                       dev_name(lttng_inode_to_bdi(inode)->dev))
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(unsigned long, state, inode->i_state)
                ctf_integer(unsigned long, dirtied_when, inode->dirtied_when)
@@ -753,8 +753,8 @@ LTTNG_TRACEPOINT_EVENT_CLASS(writeback_single_inode_template,
        TP_ARGS(inode, wbc, nr_to_write),
 
        TP_FIELDS(
-               ctf_array_text(char, name,
-                       dev_name(lttng_inode_to_bdi(inode)->dev), 32)
+               ctf_string(name,
+                       dev_name(lttng_inode_to_bdi(inode)->dev))
                ctf_integer(unsigned long, ino, inode->i_ino)
                ctf_integer(unsigned long, state, inode->i_state)
                ctf_integer(unsigned long, dirtied_when, inode->dirtied_when)