diff options
Diffstat (limited to 'contrib/pg_stat_statements/pg_stat_statements.c')
| -rw-r--r-- | contrib/pg_stat_statements/pg_stat_statements.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c index ccd24eb02a0..b62459725b9 100644 --- a/contrib/pg_stat_statements/pg_stat_statements.c +++ b/contrib/pg_stat_statements/pg_stat_statements.c @@ -408,7 +408,7 @@ _PG_init(void) &pgss_max, 5000, 100, - INT_MAX, + INT_MAX / 2, PGC_POSTMASTER, 0, NULL, @@ -2053,6 +2053,18 @@ qtext_store(const char *query, int query_len, *query_offset = off; + /* + * Don't allow the file to grow larger than what qtext_load_file can + * (theoretically) handle. This has been seen to be reachable on 32-bit + * platforms. + */ + if (unlikely(query_len >= MaxAllocHugeSize - off)) + { + errno = EFBIG; /* not quite right, but it'll do */ + fd = -1; + goto error; + } + /* Now write the data into the successfully-reserved part of the file */ fd = OpenTransientFile(PGSS_TEXT_FILE, O_RDWR | O_CREAT | PG_BINARY); if (fd < 0) @@ -2238,8 +2250,14 @@ need_gc_qtexts(void) SpinLockRelease(&s->mutex); } - /* Don't proceed if file does not exceed 512 bytes per possible entry */ - if (extent < 512 * pgss_max) + /* + * Don't proceed if file does not exceed 512 bytes per possible entry. + * + * Here and in the next test, 32-bit machines have overflow hazards if + * pgss_max and/or mean_query_len are large. Force the multiplications + * and comparisons to be done in uint64 arithmetic to forestall trouble. + */ + if ((uint64) extent < (uint64) 512 * pgss_max) return false; /* @@ -2249,7 +2267,7 @@ need_gc_qtexts(void) * query length in order to prevent garbage collection from thrashing * uselessly. */ - if (extent < pgss->mean_query_len * pgss_max * 2) + if ((uint64) extent < (uint64) pgss->mean_query_len * pgss_max * 2) return false; return true; |