THank you for this analysis. The original bug message did not contain enough context to see this interaction.
M Iain Patterson wrote: > Quoth Mark Burgess, > >> This is probably true, but the case cited in the mail is not a >> limitation of cfengine but the argument "getopt" code in the >> operating system concerned. It is normal that Unix limits to 31 >> args, and internally cfengine does the same for consistency. > > I tried compiling the getopt example code at > http://www.gnu.org/software/libc/manual/html_node/Getopt.html and > didn't get a segfault with >31 arguments on Linux x86_64. > > cfagent 2.2.1 on the same OS did indeed segfault with >31 arguments. > >> The conclusion is that, while I agree there should be no segfault, >> I am not sure what I can do about it, since there is no code in >> cfengine that lead to this fault. > > It seems the bug is in the code which preparses arguments. Line 253 > of cfagent.c (at least in version 2.2.1) describes the case where a > script is called with the shell magic > > #!/bla/cfengine -v -f > > and this ends up being passed in argv[1] as a single string. cfagent > then parses this into an array of size CF_MAXARGS, which is 31 as you > state. > > The attached quick and very dirty patch does the preparse in two > stages, first allocating a dynamic buffer big enough for the arguments > and then filling it in as before. > > An alternative option (if you excuse the pun) would be to use popt, > which has the function poptParseArgvString(). The downside is that > this is an added dependency. > > > ------------------------------------------------------------------------ > > --- cfengine-2.2.1/src/cf.defs.h.orig 2007-11-30 08:24:22.122979592 +0000 > +++ cfengine-2.2.1/src/cf.defs.h 2007-11-30 08:24:26.734643977 +0000 > @@ -287,7 +287,6 @@ > #define CF_NONCELEN (CF_BUFSIZE/16) > #define CF_MAXLINKSIZE 256 > #define CF_MAXLINKLEVEL 4 > -#define CF_MAXARGS 31 > #define CF_MAXFARGS 8 > #define CF_MAX_IP_LEN 64 /* numerical ip length */ > #define CF_PROCCOLS 16 > --- cfengine-2.2.1/src/cfagent.c.orig 2007-11-30 08:24:04.652251054 +0000 > +++ cfengine-2.2.1/src/cfagent.c 2007-11-30 08:47:17.382186413 +0000 > @@ -198,8 +198,8 @@ > > void Initialize(int argc,char *argv[]) > > -{ char *sp, *cfargv[CF_MAXARGS]; > - int i, cfargc, seed; > +{ char *sp, **cfargv; > + int i, j, cfargc, seed; > struct stat statbuf; > unsigned char s[16]; > char ebuff[CF_EXPANDSIZE]; > @@ -235,9 +235,40 @@ > /* Everything ends up inside a single argument! Here's the fix */ > > cfargc = 1; > -cfargv[0]="cfagent"; > > -for (i = 1; i < argc; i++) > +/* Pass 1: Find how many arguments there are. */ > +for (i = 1, j = 1; i < argc; i++) > + { > + sp = argv[i]; > + > + while (*sp != '\0') > + { > + while (*sp == ' ' && *sp != '\0') /* Skip to arg */ > + { > + sp++; > + } > + > + cfargc++; > + > + while (*sp != ' ' && *sp != '\0') /* Skip to white space */ > + { > + sp++; > + } > + } > + } > + > +/* Allocate memory for cfargv. */ > +cfargv = (char **) malloc(sizeof(char *) * cfargc + 1); > +if (! cfargv) > + { > + /* I guess CfLog(cferror, ...) isn't available yet. */ > + fprintf(stderr,"cfagent: Out of memory parsing arguments\n"); > + exit(111); > + } > + > +/* Pass 2: Parse the arguments. */ > +cfargv[0] = "cfagent"; > +for (i = 1, j = 1; i < argc; i++) > { > sp = argv[i]; > > @@ -252,7 +283,7 @@ > sp++; > } > > - cfargv[cfargc++] = sp; > + cfargv[j++] = sp; > > while (*sp != ' ' && *sp != '\0') /* Skip to white space */ > { > @@ -260,6 +291,7 @@ > } > } > } > +cfargv[j] = 0; > > VDEFAULTBINSERVER.name = ""; > > @@ -315,6 +347,7 @@ > seed = ElfHash(s); > srand48((long)seed); > CheckOpts(cfargc,cfargv); > + free(cfargv); > > AddInstallable("no_default_route"); > CfenginePort(); > > > ------------------------------------------------------------------------ > > _______________________________________________ > Bug-cfengine mailing list > [EMAIL PROTECTED] > https://cfengine.org/mailman/listinfo/bug-cfengine -- Mark Burgess Professor of Network and System Administration Oslo University College ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Work: +47 22453272 Email: [EMAIL PROTECTED] Fax : +47 22453205 WWW : http://www.iu.hio.no/~mark ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
