On Thu, 15 Oct 2015 13:17:50 +0200 Petr Hracek <phra...@redhat.com> wrote:
> On 10/14/2015 06:50 PM, Amadeusz Sławiński wrote: > > On Wed, 14 Oct 2015 13:45:04 +0200 > > Petr Hracek <phra...@redhat.com> wrote: > > > >> Hi Amadeusz, > >> > >> based on our last discussion, I tried to use it > >> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=644788;msg=265;att=0 > >> > >> And I guess, that If I already updated screen with different > >> message structure. > >> then now I am not able to reconnect as you mentioned. > >> Althought WriteOldMessage(&m) is used. > > Hey, > > > > Yes struct old_msg may need adjusting along with WriteOldMessage > > function, so passing new values to old_msg works. > > > > Although now that I look at this patch again, it seems very hacky. > > It copies values from attaching (new) client, into old_msg struct of > > server and attaches to it with new client. It's wonder that it > > doesn't crash, as even with copied values, struct between client > > and server are different. > > > > Amadeusz > Thanks. > I have created the patch an year ago. > > ~~~ > diff --git a/screen-fix-term.patch b/screen-fix-term.patch new file > mode 100644 index 0000000..aaef501 --- /dev/null +++ > b/screen-fix-term.patch > <http://pkgs.devel.redhat.com/cgit/rpms/screen/tree/screen-fix-term.patch?h=rhel-7.2&id=09b72887f153fefffe6cadad686240c3b5d4694b> > @@ -0,0 +1,163 @@ +diff --git a/src/acls.c b/src/acls.c > +index 3f40541..e5a32a4 100644 > +--- a/src/acls.c > ++++ b/src/acls.c > +@@ -182,7 +182,7 @@ struct acluser **up; > + #endif > + (*up)->u_Esc = DefaultEsc; > + (*up)->u_MetaEsc = DefaultMetaEsc; > +- strncpy((*up)->u_name, name, 20); > ++ strncpy((*up)->u_name, name, MAXLOGINLEN); > + (*up)->u_password = NULL; > + if (pass) > + (*up)->u_password = SaveStr(pass); > +@@ -318,8 +318,8 @@ struct acluser **up; > + return UserAdd(name, pass, up); > + if (!strcmp(name, "nobody")) /* he remains without password */ > + return -1; > +- strncpy((*up)->u_password, pass ? pass : "", 20); > +- (*up)->u_password[20] = '\0'; > ++ strncpy((*up)->u_password, pass ? pass : "", MAXLOGINLEN); > ++ (*up)->u_password[MAXLOGINLEN] = '\0'; > + return 0; > + } > + #endif > +diff --git a/src/acls.h b/src/acls.h > +index 907e953..42c7c18 100644 > +--- a/src/acls.h > ++++ b/src/acls.h > +@@ -78,7 +78,7 @@ struct plop > + typedef struct acluser > + { > + struct acluser *u_next; /* continue the main user list */ > +- char u_name[20+1]; /* login name how he showed up */ > ++ char u_name[MAXLOGINLEN + 1]; /* login name how he showed up */ > + char *u_password; /* his password (may be NullStr). */ > + int u_checkpassword; /* nonzero if this u_password is valid */ > + int u_detachwin; /* the window where he last detached */ > +diff --git a/src/comm.c b/src/comm.c > +index 5f4af8a..7705fcb 100644 > +--- a/src/comm.c > ++++ b/src/comm.c > +@@ -36,6 +36,7 @@ > + */ > + > + #include "config.h" > ++#include "os.h" > + #include "acls.h" > + #include "comm.h" > + > +diff --git a/src/display.h b/src/display.h > +index b1ab748..a433e6d 100644 > +--- a/src/display.h > ++++ b/src/display.h > +@@ -73,7 +73,7 @@ struct display > + struct win *d_other; /* pointer to other window */ > + int d_nonblock; /* -1 don't block if obufmax reached */ > + /* >0: block after nonblock secs */ > +- char d_termname[40 + 1]; /* $TERM */ > ++ char d_termname[MAXTERMLEN + 1]; /* $TERM */ > + char *d_tentry; /* buffer for tgetstr */ > + char d_tcinited; /* termcap inited flag */ > + int d_width, d_height; /* width/height of the screen */ > +diff --git a/src/os.h b/src/os.h > +index 5c17c83..bc71c97 100644 > +--- a/src/os.h > ++++ b/src/os.h > +@@ -521,3 +521,8 @@ typedef struct fd_set { int fds_bits[1]; } > fd_set; > + */ > + #define IOSIZE 4096 > + > ++/* Changing those you won't be able to attach to your old sessions > ++ * when changing those values in official tree don't forget to bump > ++ * MSG_VERSION */ > ++#define MAXTERMLEN 50 > ++#define MAXLOGINLEN 256 > +diff --git a/src/process.c b/src/process.c > +index 7817ac8..a3c2e3d 100644 > +--- a/src/process.c > ++++ b/src/process.c > +@@ -2649,9 +2649,9 @@ int key; > + s = NULL; > + if (ParseSaveStr(act, &s)) > + break; > +- if (strlen(s) >= 20) > ++ if (strlen(s) >= MAXTERMLEN) > + { > +- OutputMsg(0, "%s: term: argument too long ( < 20)", rc_name); > ++ OutputMsg(0, "%s: term: argument too long ( < %d)", rc_name, > MAXTERMLEN); > + free(s); > + break; > + } > +diff --git a/src/screen.c b/src/screen.c > +index cd0c71b..7a21762 100644 > +--- a/src/screen.c > ++++ b/src/screen.c > +@@ -995,10 +995,10 @@ char **av; > + > + if (home == 0 || *home == '\0') > + home = ppp->pw_dir; > +- if (strlen(LoginName) > 20) > ++ if (strlen(LoginName) > MAXLOGINLEN) > + Panic(0, "LoginName too long - sorry."); > + #ifdef MULTIUSER > +- if (multi && strlen(multi) > 20) > ++ if (multi && strlen(multi) > MAXLOGINLEN) > + Panic(0, "Screen owner name too long - sorry."); > + #endif > + if (strlen(home) > MAXPATHLEN - 25) > +diff --git a/src/screen.h b/src/screen.h > +index 1a388e3..30ecefb 100644 > +--- a/src/screen.h > ++++ b/src/screen.h > +@@ -202,32 +202,32 @@ struct msg > + int nargs; > + char line[MAXPATHLEN]; > + char dir[MAXPATHLEN]; > +- char screenterm[20]; /* is screen really "screen" ? */ > ++ char screenterm[MAXTERMLEN]; /* is screen really "screen" ? */ > + } > + create; > + struct > + { > +- char auser[20 + 1]; /* username */ > ++ char auser[MAXLOGINLEN + 1]; /* username */ > + int apid; /* pid of frontend */ > + int adaptflag; /* adapt window size? */ > + int lines, columns; /* display size */ > + char preselect[20]; > + int esc; /* his new escape character unless -1 */ > + int meta_esc; /* his new meta esc character unless -1 */ > +- char envterm[40 + 1]; /* terminal type */ > ++ char envterm[MAXTERMLEN + 1]; /* terminal type */ > + int encoding; /* encoding of display */ > + int detachfirst; /* whether to detach remote sessions first */ > + } > + attach; > + struct > + { > +- char duser[20 + 1]; /* username */ > ++ char duser[MAXLOGINLEN + 1]; /* username */ > + int dpid; /* pid of frontend */ > + } > + detach; > + struct > + { > +- char auser[20 + 1]; /* username */ > ++ char auser[MAXLOGINLEN + 1]; /* username */ > + int nargs; > + char cmd[MAXPATHLEN]; /* command */ > + int apid; /* pid of frontend */ > +diff --git a/src/socket.c b/src/socket.c > +index 1f04284..32c5047 100644 > +--- a/src/socket.c > ++++ b/src/socket.c > +@@ -1528,7 +1528,7 @@ static void PasswordProcessInput __P((char *, > int)); + > + struct pwdata { > + int l; > +- char buf[20 + 1]; > ++ char buf[MAXLOGINLEN + 1]; > + struct msg m; > + }; > + > > The patch is about 'LoginName too long' like you mentioned before. > This should remain I guess. > It seems that the best way will be like this say to user 'hey your > session is old and screen is not able to connect to it'. I am fine > with that. Hey, for getting warning bumping MSG_VERSION should work. Amadeusz > > Reproducer is: > 1) $screen -S foo without patch 'LoginName' and session is created > 2) appling patch mentioned above > 3) What patch shall I use for inform user that session is old and > screen doesn't hang. > > This debian patch doesn't work > https://anonscm.debian.org/cgit/collab-maint/screen.git/tree/debian/patches/60-644788-screen-4.1.0-4.0.3-interoperability.patch?h=wheezy > screen still hangs. > > What shall I do? Or How shall I patch screen so that screen will not > hang and properly inform user or at least doesn't hang? > > I have found this debian patch. > https://anonscm.debian.org/cgit/collab-maint/screen.git/tree/debian/patches/60-screen-4.2.1-debian4.1.0-compatibility.patch?h=jessie > but the patch doesn't work and screen still hangs. > > Greetings and thanks for support. > > I will be ping you on freenode if you don't mind. >
