summaryrefslogtreecommitdiffstats
path: root/kernel/audit_tree.c
AgeCommit message (Collapse)Author
2009-12-19fix more leaks in audit_tree.c tag_chunk()Al Viro
Several leaks in audit_tree didn't get caught by commit 318b6d3d7ddbcad3d6867e630711b8a705d873d7, including the leak on normal exit in case of multiple rules refering to the same chunk. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-19fix braindamage in audit_tree.c untag_chunk()Al Viro
... aka "Al had badly fscked up when writing that thing and nobody noticed until Eric had fixed leaks that used to mask the breakage". The function essentially creates a copy of old array sans one element and replaces the references to elements of original (they are on cyclic lists) with those to corresponding elements of new one. After that the old one is fair game for freeing. First of all, there's a dumb braino: when we get to list_replace_init we use indices for wrong arrays - position in new one with the old array and vice versa. Another bug is more subtle - termination condition is wrong if the element to be excluded happens to be the last one. We shouldn't go until we fill the new array, we should go until we'd finished the old one. Otherwise the element we are trying to kill will remain on the cyclic lists... That crap used to be masked by several leaks, so it was not quite trivial to hit. Eric had fixed some of those leaks a while ago and the shit had hit the fan... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-24Fix rule eviction order for AUDIT_DIRAl Viro
If syscall removes the root of subtree being watched, we definitely do not want the rules refering that subtree to be destroyed without the syscall in question having a chance to match them. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-24Audit: clean up all op= output to include string quotingEric Paris
A number of places in the audit system we send an op= followed by a string that includes spaces. Somehow this works but it's just wrong. This patch moves all of those that I could find to be quoted. Example: Change From: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1 subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op=remove rule key="number2" list=4 res=0 Change To: type=CONFIG_CHANGE msg=audit(1244666690.117:31): auid=0 ses=1 subj=unconfined_u:unconfined_r:auditctl_t:s0-s0:c0.c1023 op="remove rule" key="number2" list=4 res=0 Signed-off-by: Eric Paris <eparis@redhat.com>
2009-06-11Switch collect_mounts() to struct pathAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20No need for crossing to mountpoint in audit_tag_tree()Al Viro
is_under() will DTRT anyway. And yes, is_subdir() behaviour is intentional. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-05audit: incorrect ref counting in audit tree tag_chunkEric Paris
tag_chunk has bad exit paths in which the inotify ref counting is wrong. At the top of the function we found &old_watch using inotify_find_watch(). inotify_find_watch takes a reference to the watch. This is never dropped on an error path. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04audit: validate comparison operations, store them in sane formAl Viro
Don't store the field->op in the messy (and very inconvenient for e.g. audit_comparator()) form; translate to dense set of values and do full validation of userland-submitted value while we are at it. ->audit_init_rule() and ->audit_match_rule() get new values now; in-tree instances updated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04audit rules ordering, part 2Al Viro
Fix the actual rule listing; add per-type lists _not_ used for matching, with all exit,... sitting on one such list. Simplifies "do something for all rules" logics, while we are at it... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-11-15Fix inotify watch removal/umount racesAl Viro
Inotify watch removals suck violently. To kick the watch out we need (in this order) inode->inotify_mutex and ih->mutex. That's fine if we have a hold on inode; however, for all other cases we need to make damn sure we don't race with umount. We can *NOT* just grab a reference to a watch - inotify_unmount_inodes() will happily sail past it and we'll end with reference to inode potentially outliving its superblock. Ideally we just want to grab an active reference to superblock if we can; that will make sure we won't go into inotify_umount_inodes() until we are done. Cleanup is just deactivate_super(). However, that leaves a messy case - what if we *are* racing with umount() and active references to superblock can't be acquired anymore? We can bump ->s_count, grab ->s_umount, which will almost certainly wait until the superblock is shut down and the watch in question is pining for fjords. That's fine, but there is a problem - we might have hit the window between ->s_active getting to 0 / ->s_count - below S_BIAS (i.e. the moment when superblock is past the point of no return and is heading for shutdown) and the moment when deactivate_super() acquires ->s_umount. We could just do drop_super() yield() and retry, but that's rather antisocial and this stuff is luser-triggerable. OTOH, having grabbed ->s_umount and having found that we'd got there first (i.e. that ->s_root is non-NULL) we know that we won't race with inotify_umount_inodes(). So we could grab a reference to watch and do the rest as above, just with drop_super() instead of deactivate_super(), right? Wrong. We had to drop ih->mutex before we could grab ->s_umount. So the watch could've been gone already. That still can be dealt with - we need to save watch->wd, do idr_find() and compare its result with our pointer. If they match, we either have the damn thing still alive or we'd lost not one but two races at once, the watch had been killed and a new one got created with the same ->wd at the same address. That couldn't have happened in inotify_destroy(), but inotify_rm_wd() could run into that. Still, "new one got created" is not a problem - we have every right to kill it or leave it alone, whatever's more convenient. So we can use idr_find(...) == watch && watch->inode->i_sb == sb as "grab it and kill it" check. If it's been our original watch, we are fine, if it's a newcomer - nevermind, just pretend that we'd won the race and kill the fscker anyway; we are safe since we know that its superblock won't be going away. And yes, this is far beyond mere "not very pretty"; so's the entire concept of inotify to start with. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Greg KH <greg@kroah.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-23[PATCH] get rid of nameidata in audit_treeAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-17[PATCH] list_for_each_rcu must die: auditPaul E. McKenney
All uses of list_for_each_rcu() can be profitably replaced by the easier-to-use list_for_each_entry_rcu(). This patch makes this change for the Audit system, in preparation for removing the list_for_each_rcu() API entirely. This time with well-formed SOB. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-02-14Introduce path_put()Jan Blunck
* Add path_put() functions for releasing a reference to the dentry and vfsmount of a struct path in the right order * Switch from path_release(nd) to path_put(&nd->path) * Rename dput_path() to path_put_conditional() [akpm@linux-foundation.org: fix cifs] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: <linux-fsdevel@vger.kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14Embed a struct path into struct nameidata instead of nd->{dentry,mnt}Jan Blunck
This is the central patch of a cleanup series. In most cases there is no good reason why someone would want to use a dentry for itself. This series reflects that fact and embeds a struct path into nameidata. Together with the other patches of this series - it enforced the correct order of getting/releasing the reference count on <dentry,vfsmount> pairs - it prepares the VFS for stacking support since it is essential to have a struct path in every place where the stack can be traversed - it reduces the overall code size: without patch series: text data bss dec hex filename 5321639 858418 715768 6895825 6938d1 vmlinux with patch series: text data bss dec hex filename 5320026 858418 715768 6894212 693284 vmlinux This patch: Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix cifs] [akpm@linux-foundation.org: fix smack] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21[PATCH] audit: watching subtreesAl Viro
New kind of audit rule predicates: "object is visible in given subtree". The part that can be sanely implemented, that is. Limitations: * if you have hardlink from outside of tree, you'd better watch it too (or just watch the object itself, obviously) * if you mount something under a watched tree, tell audit that new chunk should be added to watched subtrees * if you umount something in a watched tree and it's still mounted elsewhere, you will get matches on events happening there. New command tells audit to recalculate the trees, trimming such sources of false positives. Note that it's _not_ about path - if something mounted in several places (multiple mount, bindings, different namespaces, etc.), the match does _not_ depend on which one we are using for access. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>