kernel/linux.git/security/apparmor, branch v4.19.67

apparmor: enforce nullbyte at end of tag string

2019-06-25T03:35:54+00:00

commit 8404d7a674c49278607d19726e0acc0cae299357 upstream. A packed AppArmor policy contains null-terminated tag strings that are read by unpack_nameX(). However, unpack_nameX() uses string functions on them without ensuring that they are actually null-terminated, potentially leading to out-of-bounds accesses. Make sure that the tag string is null-terminated before passing it to strcmp(). Cc: stable@vger.kernel.org Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy") Signed-off-by: Jann Horn Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

apparmor: fix PROFILE_MEDIATES for untrusted input

2019-06-25T03:35:54+00:00

commit 23375b13f98c5464c2b4d15f983cc062940f1f4e upstream. While commit 11c236b89d7c2 ("apparmor: add a default null dfa") ensure every profile has a policy.dfa it does not resize the policy.start[] to have entries for every possible start value. Which means PROFILE_MEDIATES is not safe to use on untrusted input. Unforunately commit b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE") did not take into account the start value usage. The input string in profile_query_cb() is user controlled and is not properly checked to be within the limited start[] entries, even worse it can't be as userspace policy is allowed to make us of entries types the kernel does not know about. This mean usespace can currently cause the kernel to access memory up to 240 entries beyond the start array bounds. Cc: stable@vger.kernel.org Fixes: b9590ad4c4f2 ("apparmor: remove POLICY_MEDIATES_SAFE") Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

apparmorfs: fix use-after-free on symlink traversal

2019-05-25T16:23:42+00:00

[ Upstream commit f51dcd0f621caac5380ce90fbbeafc32ce4517ae ] symlink body shouldn't be freed without an RCU delay. Switch apparmorfs to ->destroy_inode() and use of call_rcu(); free both the inode and symlink body in the callback. Signed-off-by: Al Viro Signed-off-by: Sasha Levin

apparmor: Fix aa_label_build() error handling for failed merges

2019-03-13T21:02:32+00:00

[ Upstream commit d6d478aee003e19ef90321176552a8ad2929a47f ] aa_label_merge() can return NULL for memory allocations failures make sure to handle and set the correct error in this case. Reported-by: Peng Hao Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: Fix uninitialized value in aa_split_fqname

2018-11-27T15:13:00+00:00

[ Upstream commit 250f2da49cb8e582215a65c03f50e8ddf5cd119c ] Syzkaller reported a OOB-read with the stacktrace below. This occurs inside __aa_lookupn_ns as `n` is not initialized. `n` is obtained from aa_splitn_fqname. In cases where `name` is invalid, aa_splitn_fqname returns without initializing `ns_name` and `ns_len`. Fix this by always initializing `ns_name` and `ns_len`. __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 memcmp+0xe3/0x160 lib/string.c:861 strnstr+0x4b/0x70 lib/string.c:934 __aa_lookupn_ns+0xc1/0x570 security/apparmor/policy_ns.c:209 aa_lookupn_ns+0x88/0x1e0 security/apparmor/policy_ns.c:240 aa_fqlookupn_profile+0x1b9/0x1010 security/apparmor/policy.c:468 fqlookupn_profile+0x80/0xc0 security/apparmor/label.c:1844 aa_label_strn_parse+0xa3a/0x1230 security/apparmor/label.c:1908 aa_label_parse+0x42/0x50 security/apparmor/label.c:1943 aa_change_profile+0x513/0x3510 security/apparmor/domain.c:1362 apparmor_setprocattr+0xaa4/0x1150 security/apparmor/lsm.c:658 security_setprocattr+0x66/0xc0 security/security.c:1298 proc_pid_attr_write+0x301/0x540 fs/proc/base.c:2555 __vfs_write+0x119/0x9f0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Fixes: 3b0aaf5866bf ("apparmor: add lib fn to find the "split" for fqnames") Reported-by: syzbot+61e4b490d9d2da591b50@syzkaller.appspotmail.com Signed-off-by: Zubin Mithra Reviewed-by: Kees Cook Signed-off-by: John Johansen Signed-off-by: Sasha Levin

apparmor: fix bad debug check in apparmor_secid_to_secctx()

2018-09-03T18:15:29+00:00

apparmor_secid_to_secctx() has a bad debug statement tripping on a condition handle by the code. When kconfig SECURITY_APPARMOR_DEBUG is enabled the debug WARN_ON will trip when **secdata is NULL resulting in the following trace. ------------[ cut here ]------------ AppArmor WARN apparmor_secid_to_secctx: ((!secdata)): WARNING: CPU: 0 PID: 14826 at security/apparmor/secid.c:82 apparmor_secid_to_secctx+0x2b5/0x2f0 security/apparmor/secid.c:82 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 14826 Comm: syz-executor1 Not tainted 4.19.0-rc1+ #193 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 panic+0x238/0x4e7 kernel/panic.c:184 __warn.cold.8+0x163/0x1ba kernel/panic.c:536 report_bug+0x252/0x2d0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993 RIP: 0010:apparmor_secid_to_secctx+0x2b5/0x2f0 security/apparmor/secid.c:82 Code: c7 c7 40 66 58 87 e8 6a 6d 0f fe 0f 0b e9 6c fe ff ff e8 3e aa 44 fe 48 c7 c6 80 67 58 87 48 c7 c7 a0 65 58 87 e8 4b 6d 0f fe <0f> 0b e9 3f fe ff ff 48 89 df e8 fc a7 83 fe e9 ed fe ff ff bb f4 RSP: 0018:ffff8801ba1bed10 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff8801ba1beed0 RCX: ffffc9000227e000 RDX: 0000000000018482 RSI: ffffffff8163ac01 RDI: 0000000000000001 RBP: ffff8801ba1bed30 R08: ffff8801b80ec080 R09: ffffed003b603eca R10: ffffed003b603eca R11: ffff8801db01f657 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801ba1beed0 security_secid_to_secctx+0x63/0xc0 security/security.c:1314 ctnetlink_secctx_size net/netfilter/nf_conntrack_netlink.c:621 [inline] ctnetlink_nlmsg_size net/netfilter/nf_conntrack_netlink.c:659 [inline] ctnetlink_conntrack_event+0x303/0x1470 net/netfilter/nf_conntrack_netlink.c:706 nf_conntrack_eventmask_report+0x55f/0x930 net/netfilter/nf_conntrack_ecache.c:151 nf_conntrack_event_report include/net/netfilter/nf_conntrack_ecache.h:112 [inline] nf_ct_delete+0x33c/0x5d0 net/netfilter/nf_conntrack_core.c:601 nf_ct_iterate_cleanup+0x48c/0x5e0 net/netfilter/nf_conntrack_core.c:1892 nf_ct_iterate_cleanup_net+0x23c/0x2d0 net/netfilter/nf_conntrack_core.c:1974 ctnetlink_flush_conntrack net/netfilter/nf_conntrack_netlink.c:1226 [inline] ctnetlink_del_conntrack+0x66c/0x850 net/netfilter/nf_conntrack_netlink.c:1258 nfnetlink_rcv_msg+0xd88/0x1070 net/netfilter/nfnetlink.c:228 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2454 nfnetlink_rcv+0x1c0/0x4d0 net/netfilter/nfnetlink.c:560 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2114 __sys_sendmsg+0x11d/0x290 net/socket.c:2152 __do_sys_sendmsg net/socket.c:2161 [inline] __se_sys_sendmsg net/socket.c:2159 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2159 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457089 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7bc6e03c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7bc6e046d4 RCX: 0000000000457089 RDX: 0000000000000000 RSI: 0000000020d65000 RDI: 0000000000000003 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d4588 R14: 00000000004c8d5c R15: 0000000000000000 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds.. CC: #4.18 Fixes: c092921219d2 ("apparmor: add support for mapping secids and using secctxes") Reported-by: syzbot+21016130b0580a9de3b5@syzkaller.appspotmail.com Signed-off-by: John Johansen

Merge tag 'apparmor-pr-2018-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

2018-08-24T20:00:33+00:00

Pull apparmor updates from John Johansen: "There is nothing major this time just four bug fixes and a patch to remove some dead code: Cleanups: - remove no-op permission check in policy_unpack Bug fixes: - fix an error code in __aa_create_ns() - fix failure to audit context info in build_change_hat - check buffer bounds when mapping permissions mask - fully initialize aa_perms struct when answering userspace query" * tag 'apparmor-pr-2018-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: apparmor: remove no-op permission check in policy_unpack apparmor: fix an error code in __aa_create_ns() apparmor: Fix failure to audit context info in build_change_hat apparmor: Fully initialize aa_perms struct when answering userspace query apparmor: Check buffer bounds when mapping permissions mask

apparmor: remove no-op permission check in policy_unpack

2018-08-23T01:44:42+00:00

The patch 736ec752d95e: "AppArmor: policy routines for loading and unpacking policy" from Jul 29, 2010, leads to the following static checker warning: security/apparmor/policy_unpack.c:410 verify_accept() warn: bitwise AND condition is false here security/apparmor/policy_unpack.c:413 verify_accept() warn: bitwise AND condition is false here security/apparmor/policy_unpack.c 392 #define DFA_VALID_PERM_MASK 0xffffffff 393 #define DFA_VALID_PERM2_MASK 0xffffffff 394 395 /** 396 * verify_accept - verify the accept tables of a dfa 397 * @dfa: dfa to verify accept tables of (NOT NULL) 398 * @flags: flags governing dfa 399 * 400 * Returns: 1 if valid accept tables else 0 if error 401 */ 402 static bool verify_accept(struct aa_dfa *dfa, int flags) 403 { 404 int i; 405 406 /* verify accept permissions */ 407 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { 408 int mode = ACCEPT_TABLE(dfa)[i]; 409 410 if (mode & ~DFA_VALID_PERM_MASK) 411 return 0; 412 413 if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK) 414 return 0; fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy") Reported-by: Dan Carpenter Signed-off-by: John Johansen

apparmor: fix an error code in __aa_create_ns()

2018-08-21T23:24:56+00:00

We should return error pointers in this function. Returning NULL results in a NULL dereference in the caller. Fixes: 73688d1ed0b8 ("apparmor: refactor prepare_ns() and make usable from different views") Signed-off-by: Dan Carpenter Signed-off-by: John Johansen

apparmor: Fix failure to audit context info in build_change_hat

2018-07-20T10:25:25+00:00

Cleans up clang warning: warning: variable 'info' set but not used [-Wunused-but-set-variable] Fixes: 89dbf1962aa63 ("apparmor: move change_hat mediation to using labels") Reported-by: Colin Ian King Signed-off-by: John Johansen