On 2020/07/01 22:53, Luis Chamberlain wrote: >> Well, it is not br_stp_call_user() but br_stp_start() which is expecting >> to set sub_info->retval for both KWIFEXITED() case and KWIFSIGNALED() case. >> That is, sub_info->retval needs to carry raw value (i.e. without "umh: fix >> processed error when UMH_WAIT_PROC is used" will be the correct behavior). > > br_stp_start() doesn't check for the raw value, it just checks for err > or !err. So the patch, "umh: fix processed error when UMH_WAIT_PROC is > used" propagates the correct error now. No. If "/sbin/bridge-stp virbr0 start" terminated due to e.g. SIGSEGV (for example, by inserting "kill -SEGV $$" into right after "#!/bin/sh" line), br_stp_start() needs to select BR_KERNEL_STP path. We can't assume that /sbin/bridge-stp is always terminated by exit() syscall (and hence we can't ignore KWIFSIGNALED() case in call_usermodehelper_exec_sync()).
