BMC/Intel-BMC/linux.git/security, branch v5.4.20

selinux: fall back to ref-walk if audit is required

2020-02-14T21:34:20+00:00

commit 0188d5c025ca8fe756ba3193bd7d150139af5a88 upstream. commit bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") passed down the rcu flag to the SELinux AVC, but failed to adjust the test in slow_avc_audit() to also return -ECHILD on LSM_AUDIT_DATA_DENTRY. Previously, we only returned -ECHILD if generating an audit record with LSM_AUDIT_DATA_INODE since this was only relevant from inode_permission. Move the handling of MAY_NOT_BLOCK to avc_audit() and its inlined equivalent in selinux_inode_permission() immediately after we determine that audit is required, and always fall back to ref-walk in this case. Fixes: bda0be7ad994 ("security: make inode_follow_link RCU-walk aware") Reported-by: Will Deacon Suggested-by: Al Viro Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: fix regression introduced by move_mount(2) syscall

2020-02-14T21:34:19+00:00

commit 98aa00345de54b8340dc2ddcd87f446d33387b5e upstream. commit 2db154b3ea8e ("vfs: syscall: Add move_mount(2) to move mounts around") introduced a new move_mount(2) system call and a corresponding new LSM security_move_mount hook but did not implement this hook for any existing LSM. This creates a regression for SELinux with respect to consistent checking of mounts; the existing selinux_mount hook checks mounton permission to the mount point path. Provide a SELinux hook implementation for move_mount that applies this same check for consistency. In the future we may wish to add a new move_mount filesystem permission and check as well, but this addresses the immediate regression. Fixes: 2db154b3ea8e ("vfs: syscall: Add move_mount(2) to move mounts around") Signed-off-by: Stephen Smalley Reviewed-by: Ondrej Mosnacek Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

selinux: revert "stop passing MAY_NOT_BLOCK to the AVC upon follow_link"

2020-02-14T21:34:19+00:00

commit 1a37079c236d55fb31ebbf4b59945dab8ec8764c upstream. This reverts commit e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link"). The correct fix is to instead fall back to ref-walk if audit is required irrespective of the specific audit data type. This is done in the next commit. Fixes: e46e01eebbbc ("selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link") Reported-by: Will Deacon Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

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(-)

tomoyo: Use atomic_t for statistics counter

2020-02-05T21:22:41+00:00

commit a8772fad0172aeae339144598b809fd8d4823331 upstream. syzbot is reporting that there is a race at tomoyo_stat_update() [1]. Although it is acceptable to fail to track exact number of times policy was updated, convert to atomic_t because this is not a hot path. [1] https://syzkaller.appspot.com/bug?id=a4d7b973972eeed410596e6604580e0133b0fc04 Reported-by: syzbot Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman

tomoyo: Suppress RCU warning at list_for_each_entry_rcu().

2020-01-17T18:49:05+00:00

[ Upstream commit 6bd5ce6089b561f5392460bfb654dea89356ab1b ] John Garry has reported that allmodconfig kernel on arm64 causes flood of "RCU-list traversed in non-reader section!!" warning. I don't know what change caused this warning, but this warning is safe because TOMOYO uses SRCU lock instead. Let's suppress this warning by explicitly telling that the caller is holding SRCU lock. Reported-and-tested-by: John Garry Signed-off-by: Tetsuo Handa Signed-off-by: Sasha Levin

apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock

2020-01-09T09:20:00+00:00

commit 8c62ed27a12c00e3db1c9f04bc0f272bdbb06734 upstream. aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a context protected by an rcu_read_lock. This can not be done as vfs_getxattr_alloc() may sleep regardles of the gfp_t value being passed to it. Fix this by breaking the rcu_read_lock on the policy search when the xattr match feature is requested and restarting the search if a policy changes occur. Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value") Reported-by: Jia-Ju Bai Reported-by: Al Viro Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman

tomoyo: Don't use nifty names on sockets.

2020-01-04T18:18:42+00:00

commit 6f7c41374b62fd80bbd8aae3536c43688c54d95e upstream. syzbot is reporting that use of SOCKET_I()->sk from open() can result in use after free problem [1], for socket's inode is still reachable via /proc/pid/fd/n despite destruction of SOCKET_I()->sk already completed. At first I thought that this race condition applies to only open/getattr permission checks. But James Morris has pointed out that there are more permission checks where this race condition applies to. Thus, get rid of tomoyo_get_socket_name() instead of conditionally bypassing permission checks on sockets. As a side effect of this patch, "socket:[family=\$:type=\$:protocol=\$]" in the policy files has to be rewritten to "socket:[\$]". [1] https://syzkaller.appspot.com/bug?id=73d590010454403d55164cca23bd0565b1eb3b74 Signed-off-by: Tetsuo Handa Reported-by: syzbot Reported-by: James Morris Signed-off-by: Greg Kroah-Hartman

apparmor: fix unsigned len comparison with less than zero

2020-01-04T18:18:22+00:00

[ Upstream commit 00e0590dbaec6f1bcaa36a85467d7e3497ced522 ] The sanity check in macro update_for_len checks to see if len is less than zero, however, len is a size_t so it can never be less than zero, so this sanity check is a no-op. Fix this by making len a ssize_t so the comparison will work and add ulen that is a size_t copy of len so that the min() macro won't throw warnings about comparing different types. Addresses-Coverity: ("Macro compares unsigned to 0") Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels") Signed-off-by: Colin Ian King Signed-off-by: John Johansen Signed-off-by: Sasha Levin

efi/efi_test: Lock down /dev/efi_test and require CAP_SYS_ADMIN

2019-10-31T08:40:21+00:00

The driver exposes EFI runtime services to user-space through an IOCTL interface, calling the EFI services function pointers directly without using the efivar API. Disallow access to the /dev/efi_test character device when the kernel is locked down to prevent arbitrary user-space to call EFI runtime services. Also require CAP_SYS_ADMIN to open the chardev to prevent unprivileged users to call the EFI runtime services, instead of just relying on the chardev file mode bits for this. The main user of this driver is the fwts [0] tool that already checks if the effective user ID is 0 and fails otherwise. So this change shouldn't cause any regression to this tool. [0]: https://wiki.ubuntu.com/FirmwareTestSuite/Reference/uefivarinfo Signed-off-by: Javier Martinez Canillas Signed-off-by: Ard Biesheuvel Acked-by: Laszlo Ersek Acked-by: Matthew Garrett Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191029173755.27149-7-ardb@kernel.org Signed-off-by: Ingo Molnar