Re: [PATCH v3 2/3] firmware/edd: use kobject_put() on edd_device_register() failure
| Newsgroups | org.ozlabs.lists.linuxppc-dev,dev.linux.lists.driver-core,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Hi, Bjorn Helgaas <[email protected]> writes: > On Fri, Aug 14, 2026 at 09:00:56PM +0000, Tarun Sahu wrote: >> As per koject_init_and_add() function kernel document, even if this >> function returns error kobject_put must be used instead of kfree. > > Thanks for adding this specific pointer. I wouldn't repost just for > these nits, and wait at least a few days before reposting for any > reason. But if you do repost: > > s/koject_init_and_add/kobject_init_and_add/ > > Might also add "()" after function names consistently (kobject_put and > kfree above, edd_release below). Also applies to the other patches. > > The current subject lines basically restate the C code; you might > consider more of a focus on the problem. I ran this through gemini > and I think it did a decent job: > > firmware: edd: Fix kobject reference leak on registration failure > > Per kobject_init_and_add() kernel-doc, calling kfree() directly on > error bypasses reference counting and skips the kobject's release > callback, leaking the reference. > > Use kobject_put() instead of kfree() on registration failure to fix > this. Thanks Bjron for reviewing. I will take care of them. ~Tarun > >> When edd_device_register() fails after initializing the kobject with >> kobject_init_and_add(), calling kfree(edev) directly bypasses the >> kobject release callback (edd_release) and leaks the allocated kobject >> resources. >> >> Fix this by replacing direct kfree(edev) with kobject_put(&edev->kobj) on >> registration failure. >> >> Signed-off-by: Tarun Sahu <[email protected]> >> Reviewed-by: Sourabh Jain <[email protected]> >> --- >> drivers/firmware/edd.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/firmware/edd.c b/drivers/firmware/edd.c >> index f980c5b56858..763e7b16d517 100644 >> --- a/drivers/firmware/edd.c >> +++ b/drivers/firmware/edd.c >> @@ -748,7 +748,7 @@ edd_init(void) >> >> rc = edd_device_register(edev, i); >> if (rc) { >> - kfree(edev); >> + kobject_put(&edev->kobj); >> goto out; >> } >> edd_devices[i] = edev; >> -- >> 2.55.0.691.gc56d675ccc-goog >>