NotificationsYou must be signed in to change notification settings
Fork6
Star31

Commit7d1a0f5

committed

Allow "-C variable" and "--describe-config" even to root users.

There's no really compelling reason to refuse to do these read-only,non-server-starting options as root, and there's at least one goodreason to allow -C: pg_ctl uses -C to find out the true data directorylocation when pointed at a config-only directory. On Windows, this isdone before dropping administrator privileges, which means that pg_ctlfails for administrators if and only if a config-only layout is used.Since the root-privilege check is done so early in startup, it's a bitawkward to check for these switches. Make the somewhat arbitrarydecision that we'll only skip the root check if -C is the first switch.This is not just to make the code a bit simpler: it also guarantees thatwe can't misinterpret a --boot mode switch. (While AuxiliaryProcessMaindoesn't currently recognize any such switch, it might have one in thefuture.) This is no particular problem for pg_ctl, and since the wholebehavior is undocumented anyhow, it's not a documentation issue either.(--describe-config only works as the first switch anyway, so this isno restriction for that case either.)Back-patch to 9.2 where pg_ctl first began to use -C.MauMau, heavily edited by me

1 parent598f303 commit7d1a0f5Copy full SHA for 7d1a0f5

File tree

2 files changed

+28

-6

lines changed

src
- backend/main
  - main.c
- bin/pg_ctl
  - pg_ctl.c

2 files changed

+28

-6

lines changed

`‎src/backend/main/main.c`

Lines changed: 23 additions & 3 deletions

Original file line number	Diff line number	Diff line change
`@@ -59,6 +59,8 @@ static char get_current_username(const char progname);`
`59`	`59`	`int`
`60`	`60`	`main(intargc,char*argv[])`
`61`	`61`	`{`
	`62`	`+booldo_check_root= true;`
	`63`	`+`
`62`	`64`	`progname=get_progname(argv[0]);`
`63`	`65`
`64`	`66`	`/*`
`@@ -153,7 +155,8 @@ main(int argc, char *argv[])`
`153`	`155`	`unsetenv("LC_ALL");`
`154`	`156`
`155`	`157`	`/*`
`156`		`- * Catch standard options before doing much else`
	`158`	`+ * Catch standard options before doing much else, in particular before we`
	`159`	`+ * insist on not being root.`
`157`	`160`	`*/`
`158`	`161`	`if (argc>1)`
`159`	`162`	`{`
`@@ -167,12 +170,29 @@ main(int argc, char *argv[])`
`167`	`170`	`puts("postgres (PostgreSQL) "PG_VERSION);`
`168`	`171`	`exit(0);`
`169`	`172`	`}`
	`173`	`+`
	`174`	`+/*`
	`175`	`+ * In addition to the above, we allow "--describe-config" and "-C var"`
	`176`	`+ * to be called by root. This is reasonably safe since these are`
	`177`	`+ * read-only activities. The -C case is important because pg_ctl may`
	`178`	`+ * try to invoke it while still holding administrator privileges on`
	`179`	`+ * Windows. Note that while -C can normally be in any argv position,`
	`180`	`+ * if you wanna bypass the root check you gotta put it first. This`
	`181`	`+ * reduces the risk that we might misinterpret some other mode's -C`
	`182`	`+ * switch as being the postmaster/postgres one.`
	`183`	`+ */`
	`184`	`+if (strcmp(argv[1],"--describe-config")==0)`
	`185`	`+do_check_root= false;`
	`186`	`+elseif (argc>2&&strcmp(argv[1],"-C")==0)`
	`187`	`+do_check_root= false;`
`170`	`188`	`}`
`171`	`189`
`172`	`190`	`/*`
`173`		`- * Make sure we are not running as root.`
	`191`	`+ * Make sure we are not running as root, unless it's safe for the selected`
	`192`	`+ * option.`
`174`	`193`	`*/`
`175`		`-check_root(progname);`
	`194`	`+if (do_check_root)`
	`195`	`+check_root(progname);`
`176`	`196`
`177`	`197`	`/*`
`178`	`198`	`* Dispatch to one of various subprograms depending on first argument.`

`‎src/bin/pg_ctl/pg_ctl.c`

Lines changed: 5 additions & 3 deletions

Original file line number	Diff line number	Diff line change
`@@ -1962,9 +1962,11 @@ adjust_data_dir(void)`
`1962`	`1962`	`else`
`1963`	`1963`	`my_exec_path=pg_strdup(exec_path);`
`1964`	`1964`
`1965`		`-snprintf(cmd,MAXPGPATH,SYSTEMQUOTE"\"%s\" %s%s -C data_directory"SYSTEMQUOTE,`
`1966`		`-my_exec_path,pgdata_opt ?pgdata_opt :"",post_opts ?`
`1967`		`-post_opts :"");`
	`1965`	`+/* it's important for -C to be the first option, see main.c */`
	`1966`	`+snprintf(cmd,MAXPGPATH,SYSTEMQUOTE"\"%s\" -C data_directory %s%s"SYSTEMQUOTE,`
	`1967`	`+my_exec_path,`
	`1968`	`+pgdata_opt ?pgdata_opt :"",`
	`1969`	`+post_opts ?post_opts :"");`
`1968`	`1970`
`1969`	`1971`	`fd=popen(cmd,"r");`
`1970`	`1972`	`if (fd==NULL\|\|fgets(filename,sizeof(filename),fd)==NULL)`

0 commit comments

Comments

(0)

Movatterモバイル変換

Navigation Menu

Search code, repositories, users, issues, pull requests...

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Commit7d1a0f5

File tree

2 files changed

2 files changed

`‎src/backend/main/main.c`

`‎src/bin/pg_ctl/pg_ctl.c`

0 commit comments