Re: [PATCH] pcmcia: rsrc_nonstatic: Fix memory leak in nonstatic_release_resource_db()

From: Armin Wolf
Date: Mon Jun 12 2023 - 21:35:53 EST


Am 12.05.23 um 20:45 schrieb Armin Wolf:

When nonstatic_release_resource_db() frees all resources associated
with an PCMCIA socket, it forgets to free socket_data too, causing
a memory leak observable with kmemleak:

unreferenced object 0xc28d1000 (size 64):
comm "systemd-udevd", pid 297, jiffies 4294898478 (age 194.484s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 f0 85 0e c3 00 00 00 00 ................
00 00 00 00 0c 10 8d c2 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffda4245>] __kmem_cache_alloc_node+0x2d7/0x4a0
[<7e51f0c8>] kmalloc_trace+0x31/0xa4
[<d52b4ca0>] nonstatic_init+0x24/0x1a4 [pcmcia_rsrc]
[<a2f13e08>] pcmcia_register_socket+0x200/0x35c [pcmcia_core]
[<a728be1b>] yenta_probe+0x4d8/0xa70 [yenta_socket]
[<c48fac39>] pci_device_probe+0x99/0x194
[<84b7c690>] really_probe+0x181/0x45c
[<8060fe6e>] __driver_probe_device+0x75/0x1f4
[<b9b76f43>] driver_probe_device+0x28/0xac
[<648b766f>] __driver_attach+0xeb/0x1e4
[<6e9659eb>] bus_for_each_dev+0x61/0xb4
[<25a669f3>] driver_attach+0x1e/0x28
[<d8671d6b>] bus_add_driver+0x102/0x20c
[<df0d323c>] driver_register+0x5b/0x120
[<942cd8a4>] __pci_register_driver+0x44/0x4c
[<e536027e>] __UNIQUE_ID___addressable_cleanup_module188+0x1c/0xfffff000 [iTCO_vendor_support]

Fix this by freeing socket_data too.

Tested on a Acer Travelmate 4002WLMi by manually binding/unbinding
the yenta_cardbus driver (yenta_socket).

Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
drivers/pcmcia/rsrc_nonstatic.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/pcmcia/rsrc_nonstatic.c b/drivers/pcmcia/rsrc_nonstatic.c
index 471e0c5815f3..bf9d070a4496 100644
--- a/drivers/pcmcia/rsrc_nonstatic.c
+++ b/drivers/pcmcia/rsrc_nonstatic.c
@@ -1053,6 +1053,8 @@ static void nonstatic_release_resource_db(struct pcmcia_socket *s)
q = p->next;
kfree(p);
}
+
+ kfree(data);
}


--
2.30.2

Any progress on this one?

Armin Wolf