forked from Minki/linux
mainlining shenanigans
92063f3ca7
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 <dvyukov@google.com>
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.