diff options
Diffstat (limited to 'src/backend/tcop/postgres.c')
| -rw-r--r-- | src/backend/tcop/postgres.c | 71 |
1 files changed, 56 insertions, 15 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 9145904b49a..ee63220d956 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.511 2006/10/07 16:43:28 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.512 2006/10/07 19:25:28 tgl Exp $ * * NOTES * this is the "main" module of the postgres backend and @@ -23,13 +23,20 @@ #include <signal.h> #include <fcntl.h> #include <sys/socket.h> -#if HAVE_SYS_SELECT_H +#ifdef HAVE_SYS_SELECT_H #include <sys/select.h> #endif +#ifdef HAVE_SYS_RESOURCE_H +#include <sys/resource.h> +#endif #ifdef HAVE_GETOPT_H #include <getopt.h> #endif +#ifndef HAVE_GETRUSAGE +#include "rusagestub.h" +#endif + #include "access/printtup.h" #include "access/xact.h" #include "catalog/pg_type.h" @@ -78,7 +85,7 @@ bool Log_disconnections = false; LogStmtLevel log_statement = LOGSTMT_NONE; /* GUC variable for maximum stack depth (measured in kilobytes) */ -int max_stack_depth = 2048; +int max_stack_depth = 100; /* wait N seconds to allow attach from a debugger */ int PostAuthDelay = 0; @@ -91,7 +98,7 @@ int PostAuthDelay = 0; */ /* max_stack_depth converted to bytes for speed of checking */ -static long max_stack_depth_bytes = 2048 * 1024L; +static long max_stack_depth_bytes = 100 * 1024L; /* * Stack base pointer -- initialized by PostgresMain. This is not static @@ -2490,9 +2497,7 @@ ProcessInterrupts(void) * This should be called someplace in any recursive routine that might possibly * recurse deep enough to overflow the stack. Most Unixen treat stack * overflow as an unrecoverable SIGSEGV, so we want to error out ourselves - * before hitting the hardware limit. Unfortunately we have no direct way - * to detect the hardware limit, so we have to rely on the admin to set a - * GUC variable for it ... + * before hitting the hardware limit. */ void check_stack_depth(void) @@ -2530,13 +2535,24 @@ check_stack_depth(void) } } -/* GUC assign hook to update max_stack_depth_bytes from max_stack_depth */ +/* GUC assign hook for max_stack_depth */ bool assign_max_stack_depth(int newval, bool doit, GucSource source) { - /* Range check was already handled by guc.c */ + long newval_bytes = newval * 1024L; + long stack_rlimit = get_stack_depth_rlimit(); + + if (stack_rlimit > 0 && newval_bytes > stack_rlimit - STACK_DEPTH_SLOP) + { + ereport((source >= PGC_S_INTERACTIVE) ? ERROR : LOG, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("\"max_stack_depth\" must not exceed %ldkB", + (stack_rlimit - STACK_DEPTH_SLOP) / 1024L), + errhint("Increase the platform's stack depth limit via \"ulimit -s\" or local equivalent."))); + return false; + } if (doit) - max_stack_depth_bytes = newval * 1024L; + max_stack_depth_bytes = newval_bytes; return true; } @@ -3635,11 +3651,36 @@ PostgresMain(int argc, char *argv[], const char *username) return 1; /* keep compiler quiet */ } -#ifndef HAVE_GETRUSAGE -#include "rusagestub.h" -#else -#include <sys/resource.h> -#endif /* HAVE_GETRUSAGE */ + +/* + * Obtain platform stack depth limit (in bytes) + * + * Return -1 if unlimited or not known + */ +long +get_stack_depth_rlimit(void) +{ +#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_STACK) + static long val = 0; + + /* This won't change after process launch, so check just once */ + if (val == 0) + { + struct rlimit rlim; + + if (getrlimit(RLIMIT_STACK, &rlim) < 0) + val = -1; + else if (rlim.rlim_cur == RLIM_INFINITY) + val = -1; + else + val = rlim.rlim_cur; + } + return val; +#else /* no getrlimit */ + return -1; +#endif +} + static struct rusage Save_r; static struct timeval Save_t; |