diff options
| author | trociny <trociny@FreeBSD.org> | 2012-09-17 07:32:53 +0000 |
|---|---|---|
| committer | trociny <trociny@FreeBSD.org> | 2012-09-17 07:32:53 +0000 |
| commit | 1fecf4ec8c4fb8715fbcd4c0ac5c871bad2c0da3 (patch) | |
| tree | 0b68271860c9f7a34c1e2934f16324dfea9c2e6f /usr.sbin/bsnmpd | |
| parent | 590cfc58baf40a0db7c47eeaad9b983a32a6e4ba (diff) | |
| download | FreeBSD-src-1fecf4ec8c4fb8715fbcd4c0ac5c871bad2c0da3.zip FreeBSD-src-1fecf4ec8c4fb8715fbcd4c0ac5c871bad2c0da3.tar.gz | |
In snmp_hostres, device_map table is used for consistent device table
indexing. When a device has gone it is not removed from device_map
table but just its entry_p field is set to NULL.
So when traversing device_map in disk_OS_get_ATA_disks() and
disk_OS_get_MD_disks() check for entry_p being NULL, otherwise the
bsnmpd crash is possible when a removed map entry is dereferenced.
Before the fix, for disk_OS_get_ATA_disks() the crash could be easily
reproduced running:
atacontrol detach ata1
The crash was not observed in disk_OS_get_MD_disks() because currently
snmp_hostres does no see md(4) disks: to get the device list it uses
devinfo(3), which does not return md devices.
Reported by: Miroslav Lachman 000.fbsd quip.cz
MFC after: 1 week
Diffstat (limited to 'usr.sbin/bsnmpd')
| -rw-r--r-- | usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c b/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c index 25ba56a..5675350 100644 --- a/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c +++ b/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_diskstorage_tbl.c @@ -287,6 +287,9 @@ disk_OS_get_ATA_disks(void) /* Walk over the device table looking for ata disks */ STAILQ_FOREACH(map, &device_map, link) { + /* Skip deleted entries. */ + if (map->entry_p == NULL) + continue; for (found = lookup; found->media != DSM_UNKNOWN; found++) { if (strncmp(map->name_key, found->dev_name, strlen(found->dev_name)) != 0) @@ -345,6 +348,9 @@ disk_OS_get_MD_disks(void) /* Look for md devices */ STAILQ_FOREACH(map, &device_map, link) { + /* Skip deleted entries. */ + if (map->entry_p == NULL) + continue; if (sscanf(map->name_key, "md%d", &unit) != 1) continue; |
