mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-12-28 06:44:36 -05:00
Code Issues Packages Projects Releases Wiki Activity

tracing: Do not free "head" on error path of filter_free_subsystem_filters()

Browse Source 
The variable "head" is allocated and initialized as a list before
allocating the first "item" for the list. If the allocation of "item"
fails, it frees "head" and then jumps to the label "free_now" which will
process head and free it.

This will cause a UAF of "head", and it doesn't need to free it before
jumping to the "free_now" label as that code will free it.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250610093348.33c5643a@gandalf.local.home
Fixes: a9d0aab5eb ("tracing: Fix regression of filter waiting a long time on RCU synchronization")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202506070424.lCiNreTI-lkp@intel.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt
2025-06-10 09:33:48 -04:00
committed by Steven Rostedt (Google)
parent 19272b37aa
commit 8a157d8a00
1 changed files with 1 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
kernel/trace/trace_events_filter.c
View File

@@ -1437,10 +1437,8 @@ static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir,
INIT_LIST_HEAD(&head->list);
item = kmalloc(sizeof(*item), GFP_KERNEL);
if (!item) {
kfree(head);
if (!item)
goto free_now;
}
item->filter = filter;
list_add_tail(&item->list, &head->list);