From: Vinicius Costa Gomes <vinicius.gomes@intel.com>
To: Guixin Liu <kanie@linux.alibaba.com>,
Dave Jiang <dave.jiang@intel.com>, Vinod Koul <vkoul@kernel.org>,
Frank Li <Frank.Li@kernel.org>
Cc: dmaengine@vger.kernel.org, Xunlei Pang <xlpang@linux.alibaba.com>,
oliver.yang@linux.alibaba.com
Subject: Re: [PATCH v2] dmaengine: idxd: Fix use-after-free of idxd_wq
Date: Wed, 29 Apr 2026 10:54:58 -0700 [thread overview]
Message-ID: <87tsstwt1p.fsf@intel.com> (raw)
In-Reply-To: <20260415095030.42183-1-kanie@linux.alibaba.com>
Guixin Liu <kanie@linux.alibaba.com> writes:
> We found an idxd_wq use-after-free issue with kasan
> when remove the idxd PCI device:
>
> BUG: KASAN: slab-use-after-free in idxd_device_drv_remove+0x1f8/0x240 [idxd]
> Call Trace:
> <TASK>
> dump_stack_lvl+0x32/0x50
> print_address_description.constprop.0+0x2c/0x390
> ? idxd_device_drv_remove+0x1f8/0x240 [idxd]
> print_report+0xba/0x280
> ? kasan_addr_to_slab+0x9/0xa0
> ? idxd_device_drv_remove+0x1f8/0x240 [idxd]
> kasan_report+0xab/0xe0
> ? idxd_device_drv_remove+0x1f8/0x240 [idxd]
> idxd_device_drv_remove+0x1f8/0x240 [idxd]
> device_release_driver_internal+0x391/0x560
> bus_remove_device+0x1f5/0x3f0
> device_del+0x392/0x990
> ? __pfx_device_del+0x10/0x10
> ? kobject_cleanup+0x117/0x360
> ? idxd_unregister_devices+0x229/0x320 [idxd]
> device_unregister+0x13/0xa0
> idxd_remove+0x4f/0x1b0 [idxd]
> pci_device_remove+0xa7/0x1d0
> device_release_driver_internal+0x391/0x560
> ? pci_pme_active+0x1e/0x450
> pci_stop_bus_device+0x10a/0x150
> pci_stop_and_remove_bus_device_locked+0x16/0x30
> remove_store+0xcf/0xe0
>
> Freed by task 15535:
> kasan_save_stack+0x1c/0x40
> kasan_set_track+0x21/0x30
> kasan_save_free_info+0x27/0x40
> ____kasan_slab_free+0x171/0x240
> slab_free_freelist_hook+0xde/0x190
> __kmem_cache_free+0x19e/0x310
> device_release+0x98/0x210
> kobject_cleanup+0x102/0x360
> idxd_unregister_devices+0xb3/0x320 [idxd]
> dxd_remove+0x3f/0x1b0 [idxd]
> pci_device_remove+0xa7/0x1d0
> device_release_driver_internal+0x391/0x560
> pci_stop_bus_device+0x10a/0x150
> pci_stop_and_remove_bus_device_locked+0x16/0x30
> remove_store+0xcf/0xe0
>
> In the idxd_remove() flow, when execution reaches
> idxd_unregister_devices(), all idxd_wq instances have already been
> freed. Subsequently, when device_unregister(idxd_confdev(idxd)) is
> executed, it calls into idxd_device_drv_remove() which accesses the
> already-freed idxd_wq. This fix resolves the issue by calling
> device_release_driver() before idxd_unregister_devices().
>
> Fixes: 98da0106aac0d ("dmanegine: idxd: fix resource free ordering on driver removal")
> Co-developed-by: Shuai Xue <xueshuai@linux.alibaba.com>
> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
> ---
All questions that I had after the AI review are handled:
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Cheers,
--
Vinicius
prev parent reply other threads:[~2026-04-29 17:54 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-15 9:50 [PATCH v2] dmaengine: idxd: Fix use-after-free of idxd_wq Guixin Liu
2026-04-22 21:34 ` Vinicius Costa Gomes
2026-04-23 9:01 ` Guixin Liu
2026-04-23 18:54 ` Vinicius Costa Gomes
2026-04-24 5:43 ` Guixin Liu
2026-04-24 5:56 ` Guixin Liu
2026-04-29 2:55 ` Guixin Liu
2026-04-29 17:54 ` Vinicius Costa Gomes [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87tsstwt1p.fsf@intel.com \
--to=vinicius.gomes@intel.com \
--cc=Frank.Li@kernel.org \
--cc=dave.jiang@intel.com \
--cc=dmaengine@vger.kernel.org \
--cc=kanie@linux.alibaba.com \
--cc=oliver.yang@linux.alibaba.com \
--cc=vkoul@kernel.org \
--cc=xlpang@linux.alibaba.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.