6.12-stable review patch. If anyone has any objections, please let me know.
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From: Suraj Sonawane surajsonawane0215@gmail.com
[ 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 surajsonawane0215@gmail.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 b5f5d27ee9634..649fe79d0f0cc 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");