On Mon, Feb 14, 2022 at 06:37:18PM +0900, Daehwan Jung wrote: > We added cleanup cancelled requests when ep cmd timeout on ep dequeue > because there's no complete interrupt then. But, we find out new case > that complete interrupt comes up later. list_for_each_entry_safe is > used when cleanup cancelled requests and it has vulnerabilty on multi-core > environment. dwc3_gadget_giveback unlocks dwc->lock temporarily and other > core(ISR) can get lock and try to cleanup them again. It could cause > list_del corruption and we use DWC3_EP_END_TRANSFER_PENDING to prevent it. > > 1. MTP server cancels -> ep dequeue -> ep cmd timeout(END_TRANSFER) > -> cleanup cancelled requests -> dwc3_gadget_giveback -> list_del -> release lock temporarily > 2. Complete with END_TRANSFER -> ISR(dwc3_gadget_endpoint_command_complete) gets lock > -> cleanup cancelled requests -> dwc3_gadget_giveback -> list_del > 3. MTP server process gets lock again -> tries to access POISON list(list_del corruption) > > [ 205.014697] [2: MtpServer: 5032] dwc3 10b00000.dwc3: request cancelled with wrong reason:5 > [ 205.014719] [2: MtpServer: 5032] list_del corruption, ffffff88b6963968->next is LIST_POISON1 (dead000000000100) > > Change-Id: I9df055c6c04855edd09e330300914454a6657a23 > Signed-off-by: Daehwan Jung <dh10.jung@xxxxxxxxxxx> > > Change-Id: If87c88c3bb4c17ea1a5bde2bfec1382769f7ecab > Signed-off-by: Daehwan Jung <dh10.jung@xxxxxxxxxxx> Why did you sign off on this twice? And did you run it through checkpatch.pl? It would have reminded you that Change-Id: should not be on patches :( Same for patch 1/1. Please fix. thanks, greg k-h
