kernel/linux.git/security/smack, branch v5.4.61

Smack: prevent underflow in smk_set_cipso()

2020-08-19T06:16:16+00:00

[ Upstream commit 42a2df3e829f3c5562090391b33714b2e2e5ad4a ] We have an upper bound on "maplevel" but forgot to check for negative values. Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel") Signed-off-by: Dan Carpenter Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin

Smack: fix another vsscanf out of bounds

2020-08-19T06:16:16+00:00

[ Upstream commit a6bd4f6d9b07452b0b19842044a6c3ea384b0b88 ] This is similar to commit 84e99e58e8d1 ("Smack: slab-out-of-bounds in vsscanf") where we added a bounds check on "rule". Reported-by: syzbot+a22c6092d003d6fe1122@syzkaller.appspotmail.com Fixes: f7112e6c9abf ("Smack: allow for significantly longer Smack labels v4") Signed-off-by: Dan Carpenter Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin

Smack: fix use-after-free in smk_write_relabel_self()

2020-08-11T13:33:35+00:00

commit beb4ee6770a89646659e6a2178538d2b13e2654e upstream. smk_write_relabel_self() frees memory from the task's credentials with no locking, which can easily cause a use-after-free because multiple tasks can share the same credentials structure. Fix this by using prepare_creds() and commit_creds() to correctly modify the task's credentials. Reproducer for "BUG: KASAN: use-after-free in smk_write_relabel_self": #include #include #include static void *thrproc(void *arg) { int fd = open("/sys/fs/smackfs/relabel-self", O_WRONLY); for (;;) write(fd, "foo", 3); } int main() { pthread_t t; pthread_create(&t, NULL, thrproc, NULL); thrproc(NULL); } Reported-by: syzbot+e6416dabb497a650da40@syzkaller.appspotmail.com Fixes: 38416e53936e ("Smack: limited capability for changing process label") Cc: # v4.4+ Signed-off-by: Eric Biggers Signed-off-by: Casey Schaufler Signed-off-by: Greg Kroah-Hartman

Smack: slab-out-of-bounds in vsscanf

2020-06-17T14:40:36+00:00

commit 84e99e58e8d1e26f04c097f4266e431a33987f36 upstream. Add barrier to soob. Return -EOVERFLOW if the buffer is exceeded. Suggested-by: Hillf Danton Reported-by: syzbot+bfdd4a2f07be52351350@syzkaller.appspotmail.com Signed-off-by: Casey Schaufler Signed-off-by: Greg Kroah-Hartman

smack: avoid unused 'sip' variable warning

2020-06-17T14:40:22+00:00

[ Upstream commit 00720f0e7f288d29681d265c23b22bb0f0f4e5b4 ] The mix of IS_ENABLED() and #ifdef checks has left a combination that causes a warning about an unused variable: security/smack/smack_lsm.c: In function 'smack_socket_connect': security/smack/smack_lsm.c:2838:24: error: unused variable 'sip' [-Werror=unused-variable] 2838 | struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap; Change the code to use C-style checks consistently so the compiler can handle it correctly. Fixes: 87fbfffcc89b ("broken ping to ipv6 linklocal addresses on debian buster") Signed-off-by: Arnd Bergmann Signed-off-by: Casey Schaufler Signed-off-by: Sasha Levin

broken ping to ipv6 linklocal addresses on debian buster

2020-02-11T12:35:43+00:00

commit 87fbfffcc89b92a4281b0aa53bd06af714087889 upstream. I am seeing ping failures to IPv6 linklocal addresses with Debian buster. Easiest example to reproduce is: $ ping -c1 -w1 ff02::1%eth1 connect: Invalid argument $ ping -c1 -w1 ff02::1%eth1 PING ff02::01%eth1(ff02::1%eth1) 56 data bytes 64 bytes from fe80::e0:f9ff:fe0c:37%eth1: icmp_seq=1 ttl=64 time=0.059 ms git bisect traced the failure to commit b9ef5513c99b ("smack: Check address length before reading address family") Arguably ping is being stupid since the buster version is not setting the address family properly (ping on stretch for example does): $ strace -e connect ping6 -c1 -w1 ff02::1%eth1 connect(5, {sa_family=AF_UNSPEC, sa_data="\4\1\0\0\0\0\377\2\0\0\0\0\0\0\0\0\0\0\0\0\0\1\3\0\0\0"}, 28) = -1 EINVAL (Invalid argument) but the command works fine on kernels prior to this commit, so this is breakage which goes against the Linux paradigm of "don't break userspace" Cc: stable@vger.kernel.org Reported-by: David Ahern Suggested-by: Tetsuo Handa Signed-off-by: Casey Schaufler Signed-off-by: Greg Kroah-Hartman security/smack/smack_lsm.c | 41 +++++++++++++++++++---------------------- security/smack/smack_lsm.c | 41 +++++++++++++++++++---------------------- 1 file changed, 19 insertions(+), 22 deletions(-)

Merge tag 'smack-for-5.4-rc1' of git://github.com/cschaufler/smack-next

2019-09-23T21:25:45+00:00

Pull smack updates from Casey Schaufler: "Four patches for v5.4. Nothing is major. All but one are in response to mechanically detected potential issues. The remaining patch cleans up kernel-doc notations" * tag 'smack-for-5.4-rc1' of git://github.com/cschaufler/smack-next: smack: use GFP_NOFS while holding inode_smack::smk_lock security: smack: Fix possible null-pointer dereferences in smack_socket_sock_rcv_skb() smack: fix some kernel-doc notations Smack: Don't ignore other bprm->unsafe flags if LSM_UNSAFE_PTRACE is set

smack: use GFP_NOFS while holding inode_smack::smk_lock

2019-09-04T16:37:07+00:00

inode_smack::smk_lock is taken during smack_d_instantiate(), which is called during a filesystem transaction when creating a file on ext4. Therefore to avoid a deadlock, all code that takes this lock must use GFP_NOFS, to prevent memory reclaim from waiting for the filesystem transaction to complete. Reported-by: syzbot+0eefc1e06a77d327a056@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Casey Schaufler

security: smack: Fix possible null-pointer dereferences in smack_socket_sock_rcv_skb()

2019-09-04T16:37:07+00:00

In smack_socket_sock_rcv_skb(), there is an if statement on line 3920 to check whether skb is NULL: if (skb && skb->secmark != 0) This check indicates skb can be NULL in some cases. But on lines 3931 and 3932, skb is used: ad.a.u.net->netif = skb->skb_iif; ipv6_skb_to_auditdata(skb, &ad.a, NULL); Thus, possible null-pointer dereferences may occur when skb is NULL. To fix these possible bugs, an if statement is added to check skb. These bugs are found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai Signed-off-by: Casey Schaufler

smack: fix some kernel-doc notations

2019-09-04T16:37:07+00:00

Fix/add kernel-doc notation and fix typos in security/smack/. Signed-off-by: Liguang Zhang Signed-off-by: Casey Schaufler