kernel/linux.git/security, branch v5.10.27

integrity: double check iint_cache was initialized

2021-03-30T12:31:55+00:00

commit 92063f3ca73aab794bd5408d3361fd5b5ea33079 upstream. The kernel may be built with multiple LSMs, but only a subset may be enabled on the boot command line by specifying "lsm=". Not including "integrity" on the ordered LSM list may result in a NULL deref. As reported by Dmitry Vyukov: in qemu: qemu-system-x86_64 -enable-kvm -machine q35,nvdimm -cpu max,migratable=off -smp 4 -m 4G,slots=4,maxmem=16G -hda wheezy.img -kernel arch/x86/boot/bzImage -nographic -vga std -soundhw all -usb -usbdevice tablet -bt hci -bt device:keyboard -net user,host=10.0.2.10,hostfwd=tcp::10022-:22 -net nic,model=virtio-net-pci -object memory-backend-file,id=pmem1,share=off,mem-path=/dev/zero,size=64M -device nvdimm,id=nvdimm1,memdev=pmem1 -append "console=ttyS0 root=/dev/sda earlyprintk=serial rodata=n oops=panic panic_on_warn=1 panic=86400 lsm=smack numa=fake=2 nopcid dummy_hcd.num=8" -pidfile vm_pid -m 2G -cpu host But it crashes on NULL deref in integrity_inode_get during boot: Run /sbin/init as init process BUG: kernel NULL pointer dereference, address: 000000000000001c PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc2+ #97 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-44-g88ab0c15525c-prebuilt.qemu.org 04/01/2014 RIP: 0010:kmem_cache_alloc+0x2b/0x370 mm/slub.c:2920 Code: 57 41 56 41 55 41 54 41 89 f4 55 48 89 fd 53 48 83 ec 10 44 8b 3d d9 1f 90 0b 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 31 c0 <8b> 5f 1c 4cf RSP: 0000:ffffc9000032f9d8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888017fc4f00 RCX: 0000000000000000 RDX: ffff888040220000 RSI: 0000000000000c40 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffff888019263627 R10: ffffffff83937cd1 R11: 0000000000000000 R12: 0000000000000c40 R13: ffff888019263538 R14: 0000000000000000 R15: 0000000000ffffff FS: 0000000000000000(0000) GS:ffff88802d180000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000001c CR3: 000000000b48e000 CR4: 0000000000750ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: integrity_inode_get+0x47/0x260 security/integrity/iint.c:105 process_measurement+0x33d/0x17e0 security/integrity/ima/ima_main.c:237 ima_bprm_check+0xde/0x210 security/integrity/ima/ima_main.c:474 security_bprm_check+0x7d/0xa0 security/security.c:845 search_binary_handler fs/exec.c:1708 [inline] exec_binprm fs/exec.c:1761 [inline] bprm_execve fs/exec.c:1830 [inline] bprm_execve+0x764/0x19a0 fs/exec.c:1792 kernel_execve+0x370/0x460 fs/exec.c:1973 try_to_run_init_process+0x14/0x4e init/main.c:1366 kernel_init+0x11d/0x1b8 init/main.c:1477 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Modules linked in: CR2: 000000000000001c ---[ end trace 22d601a500de7d79 ]--- Since LSMs and IMA may be configured at build time, but not enabled at run time, panic the system if "integrity" was not initialized before use. Reported-by: Dmitry Vyukov Fixes: 79f7865d844c ("LSM: Introduce "lsm=" for boottime LSM selection") Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

selinux: fix variable scope issue in live sidtab conversion

2021-03-30T12:31:53+00:00

commit 6406887a12ee5dcdaffff1a8508d91113d545559 upstream. Commit 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs") moved the selinux_policy_commit() call out of security_load_policy() into sel_write_load(), which caused a subtle yet rather serious bug. The problem is that security_load_policy() passes a reference to the convert_params local variable to sidtab_convert(), which stores it in the sidtab, where it may be accessed until the policy is swapped over and RCU synchronized. Before 02a52c5c8c3b, selinux_policy_commit() was called directly from security_load_policy(), so the convert_params pointer remained valid all the way until the old sidtab was destroyed, but now that's no longer the case and calls to sidtab_context_to_sid() on the old sidtab after security_load_policy() returns may cause invalid memory accesses. This can be easily triggered using the stress test from commit ee1a84fdfeed ("selinux: overhaul sidtab to fix bug and improve performance"): ``` function rand_cat() { echo $(( $RANDOM % 1024 )) } function do_work() { while true; do echo -n "system_u:system_r:kernel_t:s0:c$(rand_cat),c$(rand_cat)" \ >/sys/fs/selinux/context 2>/dev/null || true done } do_work >/dev/null & do_work >/dev/null & do_work >/dev/null & while load_policy; do echo -n .; sleep 0.1; done kill %1 kill %2 kill %3 ``` Fix this by allocating the temporary sidtab convert structures dynamically and passing them among the selinux_policy_{load,cancel,commit} functions. Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs") Cc: stable@vger.kernel.org Tested-by: Tyler Hicks Reviewed-by: Tyler Hicks Signed-off-by: Ondrej Mosnacek [PM: merge fuzz in security.h and services.c] Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: don't log MAC_POLICY_LOAD record on failed policy load

2021-03-30T12:31:53+00:00

commit 519dad3bcd809dc1523bf80ab0310ddb3bf00ade upstream. If sel_make_policy_nodes() fails, we should jump to 'out', not 'out1', as the latter would incorrectly log an MAC_POLICY_LOAD audit record, even though the policy hasn't actually been reloaded. The 'out1' jump label now becomes unused and can be removed. Fixes: 02a52c5c8c3b ("selinux: move policy commit after updating selinuxfs") Cc: stable@vger.kernel.org Signed-off-by: Ondrej Mosnacek Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

Revert 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file capabilities")

2021-03-17T16:06:27+00:00

commit 3b0c2d3eaa83da259d7726192cf55a137769012f upstream. It turns out that there are in fact userspace implementations that care and this recent change caused a regression. https://github.com/containers/buildah/issues/3071 As the motivation for the original change was future development, and the impact is existing real world code just revert this change and allow the ambiguity in v3 file caps. Cc: stable@vger.kernel.org Fixes: 95ebabde382c ("capabilities: Don't allow writing ambiguous v3 file capabilities") Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman

tomoyo: recognize kernel threads correctly

2021-03-09T10:11:15+00:00

commit 9c83465f3245c2faa82ffeb7016f40f02bfaa0ad upstream. Commit db68ce10c4f0a27c ("new helper: uaccess_kernel()") replaced segment_eq(get_fs(), KERNEL_DS) with uaccess_kernel(). But the correct method for tomoyo to check whether current is a kernel thread in order to assume that kernel threads are privileged for socket operations was (current->flags & PF_KTHREAD). Now that uaccess_kernel() became 0 on x86, tomoyo has to fix this problem. Do like commit 942cb357ae7d9249 ("Smack: Handle io_uring kernel thread privileges") does. Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

tomoyo: ignore data race while checking quota

2021-03-07T11:34:05+00:00

commit 5797e861e402fff2bedce4ec8b7c89f4248b6073 upstream. syzbot is reporting that tomoyo's quota check is racy [1]. But this check is tolerant of some degree of inaccuracy. Thus, teach KCSAN to ignore this data race. [1] https://syzkaller.appspot.com/bug?id=999533deec7ba6337f8aa25d8bd1a4d5f7e50476 Reported-by: syzbot Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

smackfs: restrict bytes count in smackfs write functions

2021-03-07T11:34:05+00:00

commit 7ef4c19d245f3dc233fd4be5acea436edd1d83d8 upstream. syzbot found WARNINGs in several smackfs write operations where bytes count is passed to memdup_user_nul which exceeds GFP MAX_ORDER. Check count size if bigger than PAGE_SIZE. Per smackfs doc, smk_write_net4addr accepts any label or -CIPSO, smk_write_net6addr accepts any label or -DELETE. I couldn't find any general rule for other label lengths except SMK_LABELLEN, SMK_LONGLABEL, SMK_CIPSOMAX which are documented. Let's constrain, in general, smackfs label lengths for PAGE_SIZE. Although fuzzer crashes write to smackfs/netlabel on 0x400000 length. Here is a quick way to reproduce the WARNING: python -c "print('A' * 0x400000)" > /sys/fs/smackfs/netlabel Reported-by: syzbot+a71a442385a0b2815497@syzkaller.appspotmail.com Signed-off-by: Sabyrzhan Tasbolatov Signed-off-by: Casey Schaufler Signed-off-by: Greg Kroah-Hartman

KEYS: trusted: Reserve TPM for seal and unseal operations

2021-03-04T10:38:29+00:00

commit 8c657a0590de585b1115847c17b34a58025f2f4b upstream. When TPM 2.0 trusted keys code was moved to the trusted keys subsystem, the operations were unwrapped from tpm_try_get_ops() and tpm_put_ops(), which are used to take temporarily the ownership of the TPM chip. The ownership is only taken inside tpm_send(), but this is not sufficient, as in the key load TPM2_CC_LOAD, TPM2_CC_UNSEAL and TPM2_FLUSH_CONTEXT need to be done as a one single atom. Take the TPM chip ownership before sending anything with tpm_try_get_ops() and tpm_put_ops(), and use tpm_transmit_cmd() to send TPM commands instead of tpm_send(), reverting back to the old behaviour. Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code") Reported-by: "James E.J. Bottomley" Cc: stable@vger.kernel.org Cc: David Howells Cc: Mimi Zohar Cc: Sumit Garg Acked-by Sumit Garg Tested-by: Mimi Zohar Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman

KEYS: trusted: Fix migratable=1 failing

2021-03-04T10:38:29+00:00

commit 8da7520c80468c48f981f0b81fc1be6599e3b0ad upstream. Consider the following transcript: $ keyctl add trusted kmk "new 32 blobauth=helloworld keyhandle=80000000 migratable=1" @u add_key: Invalid argument The documentation has the following description: migratable= 0|1 indicating permission to reseal to new PCR values, default 1 (resealing allowed) The consequence is that "migratable=1" should succeed. Fix this by allowing this condition to pass instead of return -EINVAL. [*] Documentation/security/keys/trusted-encrypted.rst Cc: stable@vger.kernel.org Cc: "James E.J. Bottomley" Cc: Mimi Zohar Cc: David Howells Fixes: d00a1c72f7f4 ("keys: add new trusted key-type") Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman

KEYS: trusted: Fix incorrect handling of tpm_get_random()

2021-03-04T10:38:29+00:00

commit 5df16caada3fba3b21cb09b85cdedf99507f4ec1 upstream. When tpm_get_random() was introduced, it defined the following API for the return value: 1. A positive value tells how many bytes of random data was generated. 2. A negative value on error. However, in the call sites the API was used incorrectly, i.e. as it would only return negative values and otherwise zero. Returning he positive read counts to the user space does not make any possible sense. Fix this by returning -EIO when tpm_get_random() returns a positive value. Fixes: 41ab999c80f1 ("tpm: Move tpm_get_random api into the TPM device driver") Cc: stable@vger.kernel.org Cc: Mimi Zohar Cc: "James E.J. Bottomley" Cc: David Howells Cc: Kent Yoder Signed-off-by: Jarkko Sakkinen Reviewed-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman