On Wed, 21 Apr 2021 14:59:16 +0200 Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > This reverts commit 91862cc7867bba4ee5c8fcf0ca2f1d30427b6129. > > Commits from @umn.edu addresses have been found to be submitted in "bad > faith" to try to test the kernel community's ability to review "known > malicious" changes. The result of these submissions can be found in a > paper published at the 42nd IEEE Symposium on Security and Privacy > entitled, "Open Source Insecurity: Stealthily Introducing > Vulnerabilities via Hypocrite Commits" written by Qiushi Wu (University > of Minnesota) and Kangjie Lu (University of Minnesota). > > Because of this, all submissions from this group must be reverted from > the kernel tree and will need to be re-reviewed again to determine if > they actually are a valid fix. Until that work is complete, remove this > change to ensure that no problems are being introduced into the > codebase. > I have reviewed this change, and this is a valid fix and does not need to be reverted. The code before the change is: if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) return -ENOMEM; Where that does: int trace_parser_get_init(struct trace_parser *parser, int size) { memset(parser, 0, sizeof(*parser)); parser->buffer = kmalloc(size, GFP_KERNEL); if (!parser->buffer) return 1; parser->size = size; return 0; } And the trace_parser_put() does: void trace_parser_put(struct trace_parser *parser) { kfree(parser->buffer); parser->buffer = NULL; } Hence, exiting the function without calling trace_parser_put() will indeed leak memory. Please do not revert this patch. Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> -- Steve > Cc: http > Cc: stable@xxxxxxxxxxxxxxx > Cc: Wenwen Wang <wang6495@xxxxxxx> > Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > --- > kernel/trace/trace.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 5c777627212f..faed4f44d224 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -691,10 +691,8 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, > * not modified. > */ > pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); > - if (!pid_list) { > - trace_parser_put(&parser); > + if (!pid_list) > return -ENOMEM; > - } > > pid_list->pid_max = READ_ONCE(pid_max); > > @@ -704,7 +702,6 @@ int trace_pid_write(struct trace_pid_list *filtered_pids, > > pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); > if (!pid_list->pids) { > - trace_parser_put(&parser); > kfree(pid_list); > return -ENOMEM; > }