From 6809bad4e3e5e163714aef5ff5ae8c02638bcaa4 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 15 Sep 2014 12:21:09 -0700 Subject: [PATCH] 3.14-stable patches added patches: keys-fix-termination-condition-in-assoc-array-garbage-collection.patch keys-fix-use-after-free-in-assoc_array_gc.patch --- ...on-in-assoc-array-garbage-collection.patch | 108 ++++++++++++++++++ ...fix-use-after-free-in-assoc_array_gc.patch | 38 ++++++ queue-3.14/series | 2 + 3 files changed, 148 insertions(+) create mode 100644 queue-3.14/keys-fix-termination-condition-in-assoc-array-garbage-collection.patch create mode 100644 queue-3.14/keys-fix-use-after-free-in-assoc_array_gc.patch diff --git a/queue-3.14/keys-fix-termination-condition-in-assoc-array-garbage-collection.patch b/queue-3.14/keys-fix-termination-condition-in-assoc-array-garbage-collection.patch new file mode 100644 index 00000000000..7eff8b6e79e --- /dev/null +++ b/queue-3.14/keys-fix-termination-condition-in-assoc-array-garbage-collection.patch @@ -0,0 +1,108 @@ +From 95389b08d93d5c06ec63ab49bd732b0069b7c35e Mon Sep 17 00:00:00 2001 +From: David Howells +Date: Wed, 10 Sep 2014 22:22:00 +0100 +Subject: KEYS: Fix termination condition in assoc array garbage collection + +From: David Howells + +commit 95389b08d93d5c06ec63ab49bd732b0069b7c35e upstream. + +This fixes CVE-2014-3631. + +It is possible for an associative array to end up with a shortcut node at the +root of the tree if there are more than fan-out leaves in the tree, but they +all crowd into the same slot in the lowest level (ie. they all have the same +first nibble of their index keys). + +When assoc_array_gc() returns back up the tree after scanning some leaves, it +can fall off of the root and crash because it assumes that the back pointer +from a shortcut (after label ascend_old_tree) must point to a normal node - +which isn't true of a shortcut node at the root. + +Should we find we're ascending rootwards over a shortcut, we should check to +see if the backpointer is zero - and if it is, we have completed the scan. + +This particular bug cannot occur if the root node is not a shortcut - ie. if +you have fewer than 17 keys in a keyring or if you have at least two keys that +sit into separate slots (eg. a keyring and a non keyring). + +This can be reproduced by: + + ring=`keyctl newring bar @s` + for ((i=1; i<=18; i++)); do last_key=`keyctl newring foo$i $ring`; done + keyctl timeout $last_key 2 + +Doing this: + + echo 3 >/proc/sys/kernel/keys/gc_delay + +first will speed things up. + +If we do fall off of the top of the tree, we get the following oops: + +BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 +IP: [] assoc_array_gc+0x2f7/0x540 +PGD dae15067 PUD cfc24067 PMD 0 +Oops: 0000 [#1] SMP +Modules linked in: xt_nat xt_mark nf_conntrack_netbios_ns nf_conntrack_broadcast ip6t_rpfilter ip6t_REJECT xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_ni +CPU: 0 PID: 26011 Comm: kworker/0:1 Not tainted 3.14.9-200.fc20.x86_64 #1 +Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 +Workqueue: events key_garbage_collector +task: ffff8800918bd580 ti: ffff8800aac14000 task.ti: ffff8800aac14000 +RIP: 0010:[] [] assoc_array_gc+0x2f7/0x540 +RSP: 0018:ffff8800aac15d40 EFLAGS: 00010206 +RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8800aaecacc0 +RDX: ffff8800daecf440 RSI: 0000000000000001 RDI: ffff8800aadc2bc0 +RBP: ffff8800aac15da8 R08: 0000000000000001 R09: 0000000000000003 +R10: ffffffff8136ccc7 R11: 0000000000000000 R12: 0000000000000000 +R13: 0000000000000000 R14: 0000000000000070 R15: 0000000000000001 +FS: 0000000000000000(0000) GS:ffff88011fc00000(0000) knlGS:0000000000000000 +CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b +CR2: 0000000000000018 CR3: 00000000db10d000 CR4: 00000000000006f0 +Stack: + ffff8800aac15d50 0000000000000011 ffff8800aac15db8 ffffffff812e2a70 + ffff880091a00600 0000000000000000 ffff8800aadc2bc3 00000000cd42c987 + ffff88003702df20 ffff88003702dfa0 0000000053b65c09 ffff8800aac15fd8 +Call Trace: + [] ? keyring_detect_cycle_iterator+0x30/0x30 + [] keyring_gc+0x75/0x80 + [] key_garbage_collector+0x154/0x3c0 + [] process_one_work+0x176/0x430 + [] worker_thread+0x11b/0x3a0 + [] ? rescuer_thread+0x3b0/0x3b0 + [] kthread+0xd8/0xf0 + [] ? insert_kthread_work+0x40/0x40 + [] ret_from_fork+0x7c/0xb0 + [] ? insert_kthread_work+0x40/0x40 +Code: 08 4c 8b 22 0f 84 bf 00 00 00 41 83 c7 01 49 83 e4 fc 41 83 ff 0f 4c 89 65 c0 0f 8f 5a fe ff ff 48 8b 45 c0 4d 63 cf 49 83 c1 02 <4e> 8b 34 c8 4d 85 f6 0f 84 be 00 00 00 41 f6 c6 01 0f 84 92 +RIP [] assoc_array_gc+0x2f7/0x540 + RSP +CR2: 0000000000000018 +---[ end trace 1129028a088c0cbd ]--- + +Signed-off-by: David Howells +Acked-by: Don Zickus +Signed-off-by: James Morris +Signed-off-by: Greg Kroah-Hartman + +--- + lib/assoc_array.c | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +--- a/lib/assoc_array.c ++++ b/lib/assoc_array.c +@@ -1723,11 +1723,13 @@ ascend_old_tree: + shortcut = assoc_array_ptr_to_shortcut(ptr); + slot = shortcut->parent_slot; + cursor = shortcut->back_pointer; ++ if (!cursor) ++ goto gc_complete; + } else { + slot = node->parent_slot; + cursor = ptr; + } +- BUG_ON(!ptr); ++ BUG_ON(!cursor); + node = assoc_array_ptr_to_node(cursor); + slot++; + goto continue_node; diff --git a/queue-3.14/keys-fix-use-after-free-in-assoc_array_gc.patch b/queue-3.14/keys-fix-use-after-free-in-assoc_array_gc.patch new file mode 100644 index 00000000000..4db701b2f56 --- /dev/null +++ b/queue-3.14/keys-fix-use-after-free-in-assoc_array_gc.patch @@ -0,0 +1,38 @@ +From 27419604f51a97d497853f14142c1059d46eb597 Mon Sep 17 00:00:00 2001 +From: David Howells +Date: Tue, 2 Sep 2014 13:52:20 +0100 +Subject: KEYS: Fix use-after-free in assoc_array_gc() + +From: David Howells + +commit 27419604f51a97d497853f14142c1059d46eb597 upstream. + +An edit script should be considered inaccessible by a function once it has +called assoc_array_apply_edit() or assoc_array_cancel_edit(). + +However, assoc_array_gc() is accessing the edit script just after the +gc_complete: label. + +Reported-by: Andreea-Cristina Bernat +Signed-off-by: David Howells +Reviewed-by: Andreea-Cristina Bernat +cc: shemming@brocade.com +cc: paulmck@linux.vnet.ibm.com +Signed-off-by: James Morris +Signed-off-by: Greg Kroah-Hartman + +--- + lib/assoc_array.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/lib/assoc_array.c ++++ b/lib/assoc_array.c +@@ -1735,7 +1735,7 @@ ascend_old_tree: + gc_complete: + edit->set[0].to = new_root; + assoc_array_apply_edit(edit); +- edit->array->nr_leaves_on_tree = nr_leaves_on_tree; ++ array->nr_leaves_on_tree = nr_leaves_on_tree; + return 0; + + enomem: diff --git a/queue-3.14/series b/queue-3.14/series index 0a29e2037f7..bebc6edcb3a 100644 --- a/queue-3.14/series +++ b/queue-3.14/series @@ -110,3 +110,5 @@ ib-srp-fix-deadlock-between-host-removal-and-multipathd.patch drm-nouveau-bump-version-from-1.1.1-to-1.1.2.patch vfs-fix-bad-hashing-of-dentries.patch libceph-gracefully-handle-large-reply-messages-from-the-mon.patch +keys-fix-use-after-free-in-assoc_array_gc.patch +keys-fix-termination-condition-in-assoc-array-garbage-collection.patch -- 2.47.3