From 5d679086873fe9a51354ceaddb8937ac589520d0 Mon Sep 17 00:00:00 2001 From: Suraj Sonawane Date: Sun, 24 Nov 2024 01:29:00 +0530 Subject: [PATCH] iommu: iommufd: fix WARNING in iommufd_device_unbind [ Upstream commit d9df72c6acd683adf6dd23c061f3a414ec00b1f8 ] Fix an issue detected by syzbot: WARNING in iommufd_device_unbind iommufd: Time out waiting for iommufd object to become free Resolve a warning in iommufd_device_unbind caused by a timeout while waiting for the shortterm_users reference count to reach zero. The existing 10-second timeout is insufficient in some scenarios, resulting in failures the above warning. Increase the timeout in iommufd_object_dec_wait_shortterm from 10 seconds to 60 seconds to allow sufficient time for the reference count to drop to zero. This change prevents premature timeouts and reduces the likelihood of warnings during iommufd_device_unbind. Fixes: 6f9c4d8c468c ("iommufd: Do not UAF during iommufd_put_object()") Link: https://patch.msgid.link/r/20241123195900.3176-1-surajsonawane0215@gmail.com Reported-by: syzbot+c92878e123785b1fa2db@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c92878e123785b1fa2db Tested-by: syzbot+c92878e123785b1fa2db@syzkaller.appspotmail.com Signed-off-by: Suraj Sonawane Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/iommu/iommufd/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index b5f5d27ee963..649fe79d0f0c 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -130,7 +130,7 @@ static int iommufd_object_dec_wait_shortterm(struct iommufd_ctx *ictx, if (wait_event_timeout(ictx->destroy_wait, refcount_read(&to_destroy->shortterm_users) == 0, - msecs_to_jiffies(10000))) + msecs_to_jiffies(60000))) return 0; pr_crit("Time out waiting for iommufd object to become free\n");