diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2005-11-04 10:18:40 +0000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-08 17:57:30 -0800 |
| commit | 330d57fb98a916fa8e1363846540dd420e99499a (patch) | |
| tree | 841d5e5eeda46fd95ac03c36964919818a9bc3a6 /arch/s390/appldata/appldata_base.c | |
| parent | 8546df6f357dadf1989ad8da9309c9524fd56cdf (diff) | |
[PATCH] Fix sysctl unregistration oops (CVE-2005-2709)
You could open the /proc/sys/net/ipv4/conf/<if>/<whatever> file, then
wait for interface to go away, try to grab as much memory as possible in
hope to hit the (kfreed) ctl_table. Then fill it with pointers to your
function. Then do read from file you've opened and if you are lucky,
you'll get it called as ->proc_handler() in kernel mode.
So this is at least an Oops and possibly more. It does depend on an
interface going away though, so less of a security risk than it would
otherwise be.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/s390/appldata/appldata_base.c')
| -rw-r--r-- | arch/s390/appldata/appldata_base.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/s390/appldata/appldata_base.c b/arch/s390/appldata/appldata_base.c index c9f2f60cfa5..dee6ab54984 100644 --- a/arch/s390/appldata/appldata_base.c +++ b/arch/s390/appldata/appldata_base.c @@ -592,12 +592,15 @@ int appldata_register_ops(struct appldata_ops *ops) */ void appldata_unregister_ops(struct appldata_ops *ops) { + void *table; spin_lock(&appldata_ops_lock); - unregister_sysctl_table(ops->sysctl_header); list_del(&ops->list); - kfree(ops->ctl_table); + /* at that point any incoming access will fail */ + table = ops->ctl_table; ops->ctl_table = NULL; spin_unlock(&appldata_ops_lock); + unregister_sysctl_table(ops->sysctl_header); + kfree(table); P_INFO("%s-ops unregistered!\n", ops->name); } /********************** module-ops management <END> **************************/ |