Hello, We have one script to call ssh command to do some action on other server. then output some string to the standard output, then append to one file. But the append flag doesn't take effect. # ssh -V OpenSSH_9.1p1, OpenSSL 1.1.1k FIPS 25 Mar 2021 -- scripts a.sh ssh -l root <other ssh server> "ls 1>/dev/null 2>&1" & sleep 2 echo "abc" ==== Reproduce with ksh a.sh >> ddd the "abc" will be written at the first line of file ddd; Expected, "abc" was at the last line of file ddd. Following commit, seems make enhancement for the non-blocking action; https://github.com/openssh/openssh-portable/commit/7be4ac813662f68e89f23c50de058a49aa32f7e4 Please help if the commit will cause the problem. output of systemtap 1673941921913: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8401 1673941921913: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8401 1673941921915: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8401 1673941921915: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8401 /// with flag: o_append 1673941922004: setfl: process=ssh, pid=4177330: file name =ddd, flag=8401, arg=8c01 //set with flag non-block 1673941922135: setfl: process=ssh, pid=4177330: file name =ddd, flag=8c01, arg=0 // why set to 0; 1673941923917: ext4_write_checks: inode->i_size: 8455228, name: ksh, pid=4177329, off=0, file_off=0, count=4, flag=0, file_flag=8001, filename=ddd 1673941923917: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8001 1673941923917: vfs_llseek: process=ksh, pid=4177329: file name =ddd, flag=8001 Thanks, Mark
Created attachment 3651 [details] restore exact flags at exit Thanks for the report. Could you try this patch?
Hello Miller, Thanks for your quick response and fix. The patch is good by my test. Thanks, Mark systemtap's result, the flag could be restored. time: 1673959685099: vfs_llseek: process=ksh, pid=1168362: file name =ddd, flag=8401 time: 1673959685099: vfs_llseek: process=ksh, pid=1168362: file name =ddd, flag=8401 time: 1673959685100: vfs_llseek: process=ksh, pid=1168362: file name =ddd, flag=8401 time: 1673959685101: vfs_llseek: process=ksh, pid=1168362: file name =ddd, flag=8401 time: 1673959685192: setfl: process=ssh, pid=1168363: file name =ddd, flag=8401, arg=8c01 time: 1673959685319: setfl: process=ssh, pid=1168363: file name =ddd, flag=8c01, arg=8401 time= 1673959687102: inode->i_size: 8455256, name: ksh, pid=1168362, off=0, file_off=0, count=4, flag=2, file_flag=8401, filename=ddd
Thanks this fix has been committed and will be in OpenSSH 9.2, due for release next month.
OpenSSH 9.3 has been released. Close resolved bugs