/* * Copyright 2003 PathScale, Inc. * * Licensed under the GPL */ #ifndef __UM_PTRACE_X86_64_H #define __UM_PTRACE_X86_64_H #include "linux/compiler.h" #define signal_fault signal_fault_x86_64 #define __FRAME_OFFSETS /* Needed to get the R* macros */ #include "asm/ptrace-generic.h" #undef signal_fault #define HOST_AUDIT_ARCH AUDIT_ARCH_X86_64 void signal_fault(struct pt_regs_subarch *regs, void *frame, char *where); #define FS_BASE (21 * sizeof(unsigned long)) #define GS_BASE (22 * sizeof(unsigned long)) #define DS (23 * sizeof(unsigned long)) #define ES (24 * sizeof(unsigned long)) #define FS (25 * sizeof(unsigned long)) #define GS (26 * sizeof(unsigned long)) #define PT_REGS_RBX(r) UPT_RBX(&(r)->regs) #define PT_REGS_RCX(r) UPT_RCX(&(r)->regs) #define PT_REGS_RDX(r) UPT_RDX(&(r)->regs) #define PT_REGS_RSI(r) UPT_RSI(&(r)->regs) #define PT_REGS_RDI(r) UPT_RDI(&(r)->regs) #define PT_REGS_RBP(r) UPT_RBP(&(r)->regs) #define PT_REGS_RAX(r) UPT_RAX(&(r)->regs) #define PT_REGS_R8(r) UPT_R8(&(r)->regs) #define PT_REGS_R9(r) UPT_R9(&(r)->regs) #define PT_REGS_R10(r) UPT_R10(&(r)->regs) #define PT_REGS_R11(r) UPT_R11(&(r)->regs) #define PT_REGS_R12(r) UPT_R12(&(r)->regs) #define PT_REGS_R13(r) UPT_R13(&(r)->regs) #define PT_REGS_R14(r) UPT_R14(&(r)->regs) #define PT_REGS_R15(r) UPT_R15(&(r)->regs) #define PT_REGS_FS(r) UPT_FS(&(r)->regs) #define PT_REGS_GS(r) UPT_GS(&(r)->regs) #define PT_REGS_DS(r) UPT_DS(&(r)->regs) #define PT_REGS_ES(r) UPT_ES(&(r)->regs) #define PT_REGS_SS(r) UPT_SS(&(r)->regs) #define PT_REGS_CS(r) UPT_CS(&(r)->regs) #define PT_REGS_ORIG_RAX(r) UPT_ORIG_RAX(&(r)->regs) #define PT_REGS_RIP(r) UPT_IP(&(r)->regs) #define PT_REGS_RSP(r) UPT_SP(&(r)->regs) #define PT_REGS_EFLAGS(r) UPT_EFLAGS(&(r)->regs) /* XXX */ #define user_mode(r) UPT_IS_USER(&(r)->regs) #define PT_REGS_ORIG_SYSCALL(r) PT_REGS_RAX(r) #define PT_REGS_SYSCALL_RET(r) PT_REGS_RAX(r) #define PT_FIX_EXEC_STACK(sp) do ; while(0) #define profile_pc(regs) PT_REGS_IP(regs) #endif /* * Overrides for Emacs so that we follow Linus's tabbing style. * Emacs will notice this stuff at the end of the file and automatically * adjust the settings for this buffer only. This must remain at the end * of the file. * --------------------------------------------------------------------------- * Local variables: * c-file-style: "linux" * End: */ armlinux.org.uk/linux-net-next.git/log/net/vmw_vsock?showmsg=1'>vmw_vsock

Age	Commit message (Collapse)	Author
2020-02-16	net: virtio_vsock: Enhance connection semantics	Sebastien Boeuf
	Whenever the vsock backend on the host sends a packet through the RX queue, it expects an answer on the TX queue. Unfortunately, there is one case where the host side will hang waiting for the answer and might effectively never recover if no timeout mechanism was implemented. This issue happens when the guest side starts binding to the socket, which insert a new bound socket into the list of already bound sockets. At this time, we expect the guest to also start listening, which will trigger the sk_state to move from TCP_CLOSE to TCP_LISTEN. The problem occurs if the host side queued a RX packet and triggered an interrupt right between the end of the binding process and the beginning of the listening process. In this specific case, the function processing the packet virtio_transport_recv_pkt() will find a bound socket, which means it will hit the switch statement checking for the sk_state, but the state won't be changed into TCP_LISTEN yet, which leads the code to pick the default statement. This default statement will only free the buffer, while it should also respond to the host side, by sending a packet on its TX queue. In order to simply fix this unfortunate chain of events, it is important that in case the default statement is entered, and because at this stage we know the host side is waiting for an answer, we must send back a packet containing the operation VIRTIO_VSOCK_OP_RST. One could say that a proper timeout mechanism on the host side will be enough to avoid the backend to hang. But the point of this patch is to ensure the normal use case will be provided with proper responsiveness when it comes to establishing the connection. Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>