From 192cabd6a296cbc57b3d8c05c4c89d87fc102506 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Mon, 9 Oct 2017 12:43:20 -0700 Subject: lib/digsig: fix dereference of NULL user_key_payload digsig_verify() requests a user key, then accesses its payload. However, a revoked key has a NULL payload, and we failed to check for this. request_key() *does* skip revoked keys, but there is still a window where the key can be revoked before we acquire its semaphore. Fix it by checking for a NULL payload, treating it like a key which was already revoked at the time it was requested. Fixes: 051dbb918c7f ("crypto: digital signature verification support") Reviewed-by: James Morris Cc: [v3.3+] Cc: Dmitry Kasatkin Signed-off-by: Eric Biggers Signed-off-by: David Howells --- lib/digsig.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'lib') diff --git a/lib/digsig.c b/lib/digsig.c index 03d7c63837ae..6ba6fcd92dd1 100644 --- a/lib/digsig.c +++ b/lib/digsig.c @@ -87,6 +87,12 @@ static int digsig_verify_rsa(struct key *key, down_read(&key->sem); ukp = user_key_payload_locked(key); + if (!ukp) { + /* key was revoked before we acquired its semaphore */ + err = -EKEYREVOKED; + goto err1; + } + if (ukp->datalen < sizeof(*pkh)) goto err1; -- cgit v1.2.3-58-ga151 From 7433a8d6fa60a2f6910206fa10f3550c8f11f45f Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Fri, 20 Oct 2017 12:15:52 -0700 Subject: textsearch: fix typos in library helpers Fix spellos (typos) in textsearch library helpers. Signed-off-by: Randy Dunlap Signed-off-by: David S. Miller --- lib/ts_fsm.c | 2 +- lib/ts_kmp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/ts_fsm.c b/lib/ts_fsm.c index 5696a35184e4..69557c74ef9f 100644 --- a/lib/ts_fsm.c +++ b/lib/ts_fsm.c @@ -11,7 +11,7 @@ * ========================================================================== * * A finite state machine consists of n states (struct ts_fsm_token) - * representing the pattern as a finite automation. The data is read + * representing the pattern as a finite automaton. The data is read * sequentially on an octet basis. Every state token specifies the number * of recurrences and the type of value accepted which can be either a * specific character or ctype based set of characters. The available diff --git a/lib/ts_kmp.c b/lib/ts_kmp.c index 632f783e65f1..ffbe66cbb0ed 100644 --- a/lib/ts_kmp.c +++ b/lib/ts_kmp.c @@ -27,7 +27,7 @@ * * [1] Cormen, Leiserson, Rivest, Stein * Introdcution to Algorithms, 2nd Edition, MIT Press - * [2] See finite automation theory + * [2] See finite automaton theory */ #include -- cgit v1.2.3-58-ga151 From ea6789980fdaa610d7eb63602c746bf6ec70cd2b Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 11 Oct 2017 23:32:27 +0100 Subject: assoc_array: Fix a buggy node-splitting case This fixes CVE-2017-12193. Fix a case in the assoc_array implementation in which a new leaf is added that needs to go into a node that happens to be full, where the existing leaves in that node cluster together at that level to the exclusion of new leaf. What needs to happen is that the existing leaves get moved out to a new node, N1, at level + 1 and the existing node needs replacing with one, N0, that has pointers to the new leaf and to N1. The code that tries to do this gets this wrong in two ways: (1) The pointer that should've pointed from N0 to N1 is set to point recursively to N0 instead. (2) The backpointer from N0 needs to be set correctly in the case N0 is either the root node or reached through a shortcut. Fix this by removing this path and using the split_node path instead, which achieves the same end, but in a more general way (thanks to Eric Biggers for spotting the redundancy). The problem manifests itself as: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 IP: assoc_array_apply_edit+0x59/0xe5 Fixes: 3cb989501c26 ("Add a generic associative array implementation.") Reported-and-tested-by: WU Fan Signed-off-by: David Howells Cc: stable@vger.kernel.org [v3.13-rc1+] Signed-off-by: Linus Torvalds --- lib/assoc_array.c | 51 +++++++++++++++++---------------------------------- 1 file changed, 17 insertions(+), 34 deletions(-) (limited to 'lib') diff --git a/lib/assoc_array.c b/lib/assoc_array.c index 155c55d8db5f..4e53be8bc590 100644 --- a/lib/assoc_array.c +++ b/lib/assoc_array.c @@ -598,21 +598,31 @@ static bool assoc_array_insert_into_terminal_node(struct assoc_array_edit *edit, if ((edit->segment_cache[ASSOC_ARRAY_FAN_OUT] ^ base_seg) == 0) goto all_leaves_cluster_together; - /* Otherwise we can just insert a new node ahead of the old - * one. + /* Otherwise all the old leaves cluster in the same slot, but + * the new leaf wants to go into a different slot - so we + * create a new node (n0) to hold the new leaf and a pointer to + * a new node (n1) holding all the old leaves. + * + * This can be done by falling through to the node splitting + * path. */ - goto present_leaves_cluster_but_not_new_leaf; + pr_devel("present leaves cluster but not new leaf\n"); } split_node: pr_devel("split node\n"); - /* We need to split the current node; we know that the node doesn't - * simply contain a full set of leaves that cluster together (it - * contains meta pointers and/or non-clustering leaves). + /* We need to split the current node. The node must contain anything + * from a single leaf (in the one leaf case, this leaf will cluster + * with the new leaf) and the rest meta-pointers, to all leaves, some + * of which may cluster. + * + * It won't contain the case in which all the current leaves plus the + * new leaves want to cluster in the same slot. * * We need to expel at least two leaves out of a set consisting of the - * leaves in the node and the new leaf. + * leaves in the node and the new leaf. The current meta pointers can + * just be copied as they shouldn't cluster with any of the leaves. * * We need a new node (n0) to replace the current one and a new node to * take the expelled nodes (n1). @@ -717,33 +727,6 @@ found_slot_for_multiple_occupancy: pr_devel("<--%s() = ok [split node]\n", __func__); return true; -present_leaves_cluster_but_not_new_leaf: - /* All the old leaves cluster in the same slot, but the new leaf wants - * to go into a different slot, so we create a new node to hold the new - * leaf and a pointer to a new node holding all the old leaves. - */ - pr_devel("present leaves cluster but not new leaf\n"); - - new_n0->back_pointer = node->back_pointer; - new_n0->parent_slot = node->parent_slot; - new_n0->nr_leaves_on_branch = node->nr_leaves_on_branch; - new_n1->back_pointer = assoc_array_node_to_ptr(new_n0); - new_n1->parent_slot = edit->segment_cache[0]; - new_n1->nr_leaves_on_branch = node->nr_leaves_on_branch; - edit->adjust_count_on = new_n0; - - for (i = 0; i < ASSOC_ARRAY_FAN_OUT; i++) - new_n1->slots[i] = node->slots[i]; - - new_n0->slots[edit->segment_cache[0]] = assoc_array_node_to_ptr(new_n0); - edit->leaf_p = &new_n0->slots[edit->segment_cache[ASSOC_ARRAY_FAN_OUT]]; - - edit->set[0].ptr = &assoc_array_ptr_to_node(node->back_pointer)->slots[node->parent_slot]; - edit->set[0].to = assoc_array_node_to_ptr(new_n0); - edit->excised_meta[0] = assoc_array_node_to_ptr(node); - pr_devel("<--%s() = ok [insert node before]\n", __func__); - return true; - all_leaves_cluster_together: /* All the leaves, new and old, want to cluster together in this node * in the same slot, so we have to replace this node with a shortcut to -- cgit v1.2.3-58-ga151 From b39ab98e2f4728d98973fd1bc531e3c4cbccb21c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 30 Oct 2017 10:09:56 -0700 Subject: Mark 'ioremap_page_range()' as possibly sleeping It turns out that some drivers seem to think it's ok to remap page ranges from within interrupts and even NMI's. That is definitely not the case, since the page table build-up is simply not interrupt-safe. This showed up in the zero-day robot that reported it for the ACPI APEI GHES ("Generic Hardware Error Source") driver. Normally it had been hidden by the fact that no page table operations had been needed because the vmalloc area had been set up by other things. Apparently due to a recent change to the GHEI driver: commit 77b246b32b2c ("acpi: apei: check for pending errors when probing GHES entries") 0day actually caught a case during bootup whenthe ioremap called down to page allocation. But that recent change only showed the symptom, it wasn't the root cause of the problem. Hopefully it is limited to just that one driver. If you need to access random physical memory, you either need to ioremap in process context, or you need to use the FIXMAP facility to set one particular fixmap entry to the required mapping - that can be done safely. Cc: Borislav Petkov Cc: Len Brown Cc: Tony Luck Cc: Fengguang Wu Cc: Tyler Baicar Cc: Will Deacon Signed-off-by: Linus Torvalds --- lib/ioremap.c | 1 + 1 file changed, 1 insertion(+) (limited to 'lib') diff --git a/lib/ioremap.c b/lib/ioremap.c index 4bb30206b942..c835f9080c43 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -161,6 +161,7 @@ int ioremap_page_range(unsigned long addr, unsigned long next; int err; + might_sleep(); BUG_ON(addr >= end); start = addr; -- cgit v1.2.3-58-ga151