Re: [PATCH] pinctrl: core: fix possible memory leak in pinctrl_enable()

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Fri, Oct 22, 2021 at 3:36 AM Yang Yingliang <yangyingliang@xxxxxxxxxx> wrote:

> I got memory leak as follows when doing fault injection test:
>
> unreferenced object 0xffff888020a7a680 (size 64):
>   comm "i2c-mcp23018-41", pid 23090, jiffies 4295160544 (age 8.680s)
>   hex dump (first 32 bytes):
>     00 48 d3 1e 80 88 ff ff 00 1a 56 c1 ff ff ff ff  .H........V.....
>     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>   backtrace:
>     [<0000000083c79b35>] kmem_cache_alloc_trace+0x16d/0x360
>     [<0000000051803c95>] pinctrl_init_controller+0x6ed/0xb70
>     [<0000000064346707>] pinctrl_register+0x27/0x80
>     [<0000000029b0e186>] devm_pinctrl_register+0x5b/0xe0
>     [<00000000391f5a3e>] mcp23s08_probe_one+0x968/0x118a [pinctrl_mcp23s08]
>     [<000000006112c039>] mcp230xx_probe+0x266/0x560 [pinctrl_mcp23s08_i2c]
>
> If pinctrl_claim_hogs() fails, the 'pindesc' allocated in pinctrl_register_one_pin()
> need be freed.
>
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Fixes: 950b0d91dc10 ("pinctrl: core: Fix regression caused by delayed work for hogs")
> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>

Excellent find and fix!

Thanks so much Yang!

Patch applied and tagged for stable.

Yours,
Linus Walleij