Alvaro Herrera wrote:
> > In addition to that, it might be a good idea to do what the comment in the
> > code suggests, namely do more than zero checking on each file name to try
> > to make sure it looks like a stats temp file name that we'd generate
> > before we delete it. The ownership/permissions test wouldn't be enough
> > to prevent you from pointing at, say, ~postgres and thereby losing some
> > files you'd rather not.
>
> This seems pretty simple to do; see second attachment. (It would delete
> files named, "db_1234.tmpfoobar", that is, valid names with suffixes,
> but I can't see that being a problem). (I haven't really tested this
> part at all.)
Here's the second attachment.
--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
*** a/src/backend/postmaster/pgstat.c
--- b/src/backend/postmaster/pgstat.c
***************
*** 562,576 **** pgstat_reset_remove_files(const char *directory)
struct dirent *entry;
char fname[MAXPGPATH];
! dir = AllocateDir(pgstat_stat_directory);
! while ((entry = ReadDir(dir, pgstat_stat_directory)) != NULL)
{
if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
continue;
! /* XXX should we try to ignore files other than the ones we write? */
! snprintf(fname, MAXPGPATH, "%s/%s", pgstat_stat_directory,
entry->d_name);
unlink(fname);
}
--- 562,589 ----
struct dirent *entry;
char fname[MAXPGPATH];
! dir = AllocateDir(directory);
! while ((entry = ReadDir(dir, directory)) != NULL)
{
+ Oid tmp_oid;
+ char tmp_type[5];
+ int nitems;
+
if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
continue;
! /*
! * Skip directory entries that don't match the file names we write.
! * See get_dbstat_filename for the pattern.
! */
! nitems = sscanf(fname, "db_%u.%4s", &tmp_oid, tmp_type);
! if (nitems != 2)
! continue;
! if (strncmp(tmp_type, "tmp", 4) != 0 &&
! strncmp(tmp_type, "stat", 4) != 0)
! continue;
! snprintf(fname, MAXPGPATH, "%s/%s", directory,
entry->d_name);
unlink(fname);
}
***************
*** 3627,3632 **** get_dbstat_filename(bool permanent, bool tempname, Oid databaseid,
--- 3640,3646 ----
{
int printed;
+ /* NB -- pgstat_reset_remove_files knows about the pattern this uses */
printed = snprintf(filename, len, "%s/db_%u.%s",
permanent ? PGSTAT_STAT_PERMANENT_DIRECTORY :
pgstat_stat_directory,
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