Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
Find a file
Sagi Grimberg 147b27e4bd nvme-pci: allocate device queues storage space at probe
It may cause race by setting 'nvmeq' in nvme_init_request()
because .init_request is called inside switching io scheduler, which
may happen when the NVMe device is being resetted and its nvme queues
are being freed and created. We don't have any sync between the two
pathes.

This patch changes the nvmeq allocation to occur at probe time so
there is no way we can dereference it at init_request.

[   93.268391] kernel BUG at drivers/nvme/host/pci.c:408!
[   93.274146] invalid opcode: 0000 [#1] SMP
[   93.278618] Modules linked in: nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss
nfsv4 dns_resolver nfs lockd grace fscache sunrpc ipmi_ssif vfat fat
intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel
kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel iTCO_wdt
intel_cstate ipmi_si iTCO_vendor_support intel_uncore mxm_wmi mei_me
ipmi_devintf intel_rapl_perf pcspkr sg ipmi_msghandler lpc_ich dcdbas mei
shpchp acpi_power_meter wmi dm_multipath ip_tables xfs libcrc32c sd_mod
mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt
fb_sys_fops ttm drm ahci libahci nvme libata crc32c_intel nvme_core tg3
megaraid_sas ptp i2c_core pps_core dm_mirror dm_region_hash dm_log dm_mod
[   93.349071] CPU: 5 PID: 1842 Comm: sh Not tainted 4.15.0-rc2.ming+ #4
[   93.356256] Hardware name: Dell Inc. PowerEdge R730xd/072T6D, BIOS 2.5.5 08/16/2017
[   93.364801] task: 00000000fb8abf2a task.stack: 0000000028bd82d1
[   93.371408] RIP: 0010:nvme_init_request+0x36/0x40 [nvme]
[   93.377333] RSP: 0018:ffffc90002537ca8 EFLAGS: 00010246
[   93.383161] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000008
[   93.391122] RDX: 0000000000000000 RSI: ffff880276ae0000 RDI: ffff88047bae9008
[   93.399084] RBP: ffff88047bae9008 R08: ffff88047bae9008 R09: 0000000009dabc00
[   93.407045] R10: 0000000000000004 R11: 000000000000299c R12: ffff880186bc1f00
[   93.415007] R13: ffff880276ae0000 R14: 0000000000000000 R15: 0000000000000071
[   93.422969] FS:  00007f33cf288740(0000) GS:ffff88047ba80000(0000) knlGS:0000000000000000
[   93.431996] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   93.438407] CR2: 00007f33cf28e000 CR3: 000000047e5bb006 CR4: 00000000001606e0
[   93.446368] Call Trace:
[   93.449103]  blk_mq_alloc_rqs+0x231/0x2a0
[   93.453579]  blk_mq_sched_alloc_tags.isra.8+0x42/0x80
[   93.459214]  blk_mq_init_sched+0x7e/0x140
[   93.463687]  elevator_switch+0x5a/0x1f0
[   93.467966]  ? elevator_get.isra.17+0x52/0xc0
[   93.472826]  elv_iosched_store+0xde/0x150
[   93.477299]  queue_attr_store+0x4e/0x90
[   93.481580]  kernfs_fop_write+0xfa/0x180
[   93.485958]  __vfs_write+0x33/0x170
[   93.489851]  ? __inode_security_revalidate+0x4c/0x60
[   93.495390]  ? selinux_file_permission+0xda/0x130
[   93.500641]  ? _cond_resched+0x15/0x30
[   93.504815]  vfs_write+0xad/0x1a0
[   93.508512]  SyS_write+0x52/0xc0
[   93.512113]  do_syscall_64+0x61/0x1a0
[   93.516199]  entry_SYSCALL64_slow_path+0x25/0x25
[   93.521351] RIP: 0033:0x7f33ce96aab0
[   93.525337] RSP: 002b:00007ffe57570238 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   93.533785] RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f33ce96aab0
[   93.541746] RDX: 0000000000000006 RSI: 00007f33cf28e000 RDI: 0000000000000001
[   93.549707] RBP: 00007f33cf28e000 R08: 000000000000000a R09: 00007f33cf288740
[   93.557669] R10: 00007f33cf288740 R11: 0000000000000246 R12: 00007f33cec42400
[   93.565630] R13: 0000000000000006 R14: 0000000000000001 R15: 0000000000000000
[   93.573592] Code: 4c 8d 40 08 4c 39 c7 74 16 48 8b 00 48 8b 04 08 48 85 c0
74 16 48 89 86 78 01 00 00 31 c0 c3 8d 4a 01 48 63 c9 48 c1 e1 03 eb de <0f>
0b 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 85 f6 53 48 89
[   93.594676] RIP: nvme_init_request+0x36/0x40 [nvme] RSP: ffffc90002537ca8
[   93.602273] ---[ end trace 810dde3993e5f14e ]---

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15 16:20:11 +01:00
arch Revert "mm: replace p??_write with pte_access_permitted in fault + gup paths" 2017-12-15 18:53:22 -08:00
block blk-mq: fix bad clear of RQF_MQ_INFLIGHT in blk_mq_ct_ctx_init() 2018-01-14 10:46:24 -07:00
certs License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crypto crypto: scompress - use sgl_alloc() and sgl_free() 2018-01-06 09:18:00 -07:00
Documentation Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2017-12-15 12:46:48 -08:00
drivers nvme-pci: allocate device queues storage space at probe 2018-01-15 16:20:11 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs writeback: update comment in inode_io_list_move_locked 2018-01-06 09:18:00 -07:00
include block: rearrange a few request fields for better cache layout 2018-01-10 11:47:58 -07:00
init main: kernel_start: move housekeeping_init() before workqueue_init_early() 2017-11-27 08:56:57 -08:00
ipc Rename superblock flags (MS_xyz -> SB_xyz) 2017-11-27 13:05:09 -08:00
kernel genirq/affinity: assign vectors to all possible CPUs 2018-01-12 11:01:38 -07:00
lib lib/scatterlist: Introduce sgl_alloc() and sgl_free() 2018-01-06 09:18:00 -07:00
mm block: convert to bio_first_bvec_all & bio_first_page_all 2018-01-06 09:18:00 -07:00
net NFS client fixes for Linux 4.15-rc4 2017-12-16 13:12:53 -08:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2017-12-03 13:08:30 -05:00
scripts Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-15 11:44:59 -08:00
security KEYS: reject NULL restriction string when type is specified 2017-12-08 15:13:29 +00:00
sound sound fixes for 4.15-rc3 2017-12-06 10:49:14 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-15 13:08:37 -08:00
usr initramfs: fix initramfs rebuilds w/ compression after disabling 2017-11-03 07:39:19 -07:00
virt KVM: x86: fix APIC page invalidation 2017-12-06 16:10:34 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild misc updates for v4.15 2017-11-17 17:51:33 -08:00
.mailmap Add Jason Gunthorpe as co-maintainer of the RDMA stack 2017-11-17 09:36:18 -08:00
COPYING
CREDITS MAINTAINERS: update TPM driver infrastructure changes 2017-11-09 17:58:40 -08:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-12-15 13:08:37 -08:00
Makefile Linux 4.15-rc4 2017-12-17 18:59:59 -08:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.