On Mon, 17 Aug 2026 10:30:14 +0200 Ella Ma <[email protected]> wrote:
> Before applying the __free annotation, the original version goes to > label `fail_address_parse`, and does not call function > `free_trace_uprobe` on pointer `tu`. However, after the change, the > function will be called whenever the function returns. This makes the > error value returned by `alloc_trace_uprobe` get freed. > > This patch fixes this issue by adding the check for error value in the > __free function definition. > > Found by Clang Static Analyzer (my own development fork > https://github.com/Snape3058/llvm-patch-revision/tree/cleanup). > > warning: Argument to 'kfree()' is a constant address > (18446744073709551604), which is not memory allocated by > 'malloc()' [unix.Malloc] > Ah, thanks for the patch. Actually Andi sent the similar fix. https://lore.kernel.org/all/[email protected]/ which is more optimized one (remove redundant NULL check and allow passing ERRPTR to free_trace_uprobe().) Thanks, > Fixes: 8b658df20658 ("tracing: uprobes: Cleanup __trace_uprobe_create() with > __free()") > Signed-off-by: Ella Ma <[email protected]> > --- > kernel/trace/trace_uprobe.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c > index c274346853d1..ccbdc96e5578 100644 > --- a/kernel/trace/trace_uprobe.c > +++ b/kernel/trace/trace_uprobe.c > @@ -533,7 +533,7 @@ static int register_trace_uprobe(struct trace_uprobe *tu) > return ret; > } > > -DEFINE_FREE(free_trace_uprobe, struct trace_uprobe *, if (_T) > free_trace_uprobe(_T)) > +DEFINE_FREE(free_trace_uprobe, struct trace_uprobe *, if > (!IS_ERR_OR_NULL(_T)) free_trace_uprobe(_T)) > > /* > * Argument syntax: > -- > 2.34.1 > -- Masami Hiramatsu (Google) <[email protected]>
