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
Jan Glauber 0711e8c1b4 ipmi: Fix timer race with module unload
Please note that below oops is from an older kernel, but the same
race seems to be present in the upstream kernel too.

---8<---

The following panic was encountered during removing the ipmi_ssif
module:

[ 526.352555] Unable to handle kernel paging request at virtual address ffff000006923090
[ 526.360464] Mem abort info:
[ 526.363257] ESR = 0x86000007
[ 526.366304] Exception class = IABT (current EL), IL = 32 bits
[ 526.372221] SET = 0, FnV = 0
[ 526.375269] EA = 0, S1PTW = 0
[ 526.378405] swapper pgtable: 4k pages, 48-bit VAs, pgd = 000000008ae60416
[ 526.385185] [ffff000006923090] *pgd=000000bffcffe803, *pud=000000bffcffd803, *pmd=0000009f4731a003, *pte=0000000000000000
[ 526.396141] Internal error: Oops: 86000007 [#1] SMP
[ 526.401008] Modules linked in: nls_iso8859_1 ipmi_devintf joydev input_leds ipmi_msghandler shpchp sch_fq_codel ib_iser rdma_cm iw_cm ib_cm ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear i2c_smbus hid_generic usbhid uas hid usb_storage ast aes_ce_blk i2c_algo_bit aes_ce_cipher qede ttm crc32_ce ptp crct10dif_ce drm_kms_helper ghash_ce syscopyarea sha2_ce sysfillrect sysimgblt pps_core fb_sys_fops sha256_arm64 sha1_ce mpt3sas qed drm raid_class ahci scsi_transport_sas libahci gpio_xlp i2c_xlp9xx aes_neon_bs aes_neon_blk crypto_simd cryptd aes_arm64 [last unloaded: ipmi_ssif]
[ 526.468085] CPU: 125 PID: 0 Comm: swapper/125 Not tainted 4.15.0-35-generic #38~lp1775396+build.1
[ 526.476942] Hardware name: To be filled by O.E.M. Saber/Saber, BIOS 0ACKL022 08/14/2018
[ 526.484932] pstate: 00400009 (nzcv daif +PAN -UAO)
[ 526.489713] pc : 0xffff000006923090
[ 526.493198] lr : call_timer_fn+0x34/0x178
[ 526.497194] sp : ffff000009b0bdd0
[ 526.500496] x29: ffff000009b0bdd0 x28: 0000000000000082
[ 526.505796] x27: 0000000000000002 x26: ffff000009515188
[ 526.511096] x25: ffff000009515180 x24: ffff0000090f1018
[ 526.516396] x23: ffff000009519660 x22: dead000000000200
[ 526.521696] x21: ffff000006923090 x20: 0000000000000100
[ 526.526995] x19: ffff809eeb466a40 x18: 0000000000000000
[ 526.532295] x17: 000000000000000e x16: 0000000000000007
[ 526.537594] x15: 0000000000000000 x14: 071c71c71c71c71c
[ 526.542894] x13: 0000000000000000 x12: 0000000000000000
[ 526.548193] x11: 0000000000000001 x10: ffff000009b0be88
[ 526.553493] x9 : 0000000000000000 x8 : 0000000000000005
[ 526.558793] x7 : ffff80befc1f8528 x6 : 0000000000000020
[ 526.564092] x5 : 0000000000000040 x4 : 0000000020001b20
[ 526.569392] x3 : 0000000000000000 x2 : ffff809eeb466a40
[ 526.574692] x1 : ffff000006923090 x0 : ffff809eeb466a40
[ 526.579992] Process swapper/125 (pid: 0, stack limit = 0x000000002eb50acc)
[ 526.586854] Call trace:
[ 526.589289] 0xffff000006923090
[ 526.592419] expire_timers+0xc8/0x130
[ 526.596070] run_timer_softirq+0xec/0x1b0
[ 526.600070] __do_softirq+0x134/0x328
[ 526.603726] irq_exit+0xc8/0xe0
[ 526.606857] __handle_domain_irq+0x6c/0xc0
[ 526.610941] gic_handle_irq+0x84/0x188
[ 526.614679] el1_irq+0xe8/0x180
[ 526.617822] cpuidle_enter_state+0xa0/0x328
[ 526.621993] cpuidle_enter+0x34/0x48
[ 526.625564] call_cpuidle+0x44/0x70
[ 526.629040] do_idle+0x1b8/0x1f0
[ 526.632256] cpu_startup_entry+0x2c/0x30
[ 526.636174] secondary_start_kernel+0x11c/0x130
[ 526.640694] Code: bad PC value
[ 526.643800] ---[ end trace d020b0b8417c2498 ]---
[ 526.648404] Kernel panic - not syncing: Fatal exception in interrupt
[ 526.654778] SMP: stopping secondary CPUs
[ 526.658734] Kernel Offset: disabled
[ 526.662211] CPU features: 0x5800c38
[ 526.665688] Memory Limit: none
[ 526.668768] ---[ end Kernel panic - not syncing: Fatal exception in interrupt

Prevent mod_timer from arming a timer that was already removed by
del_timer during module unload.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Cc: <stable@vger.kernel.org> # 3.19
Signed-off-by: Corey Minyard <cminyard@mvista.com>
2018-10-11 20:08:27 -05:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-15 08:02:46 -10:00
block blk-cgroup: increase number of supported policies 2018-09-11 10:59:53 -06:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
Documentation Code of Conduct: Let's revamp it. 2018-09-16 11:42:28 -07:00
drivers ipmi: Fix timer race with module unload 2018-10-11 20:08:27 -05:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs fixes for four CIFS/SMB3 potential pointer overflow issues, one minor build fix, and a build warning cleanup 2018-09-14 19:33:42 -10:00
include pci:ipmi: Move IPMI PCI class id defines to pci_ids.h 2018-09-18 16:15:33 -05:00
init Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
ipc ipc/shm: properly return EIDRM in shm_lock() 2018-09-04 16:45:02 -07:00
kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-15 08:00:37 -10:00
lib lib/Kconfig.debug: fix three typos in help text 2018-09-04 16:45:02 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm overlayfs fixes for 4.19-rc4 2018-09-13 19:21:40 -10:00
net tipc: check return value of __tipc_dump_start() 2018-09-12 13:15:04 -07:00
samples samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM 2018-08-16 21:55:32 +02:00
scripts Kbuild fixes for v4.19 2018-09-09 05:42:11 -07:00
security Revert "x86/mm/legacy: Populate the user page-table with user pgd's" 2018-09-14 17:08:45 +02:00
sound ALSA: hda: Fix several mismatch for register mask and value 2018-09-03 23:47:40 +02:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-15 06:44:32 -10:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: Remove obsolete kvm_unmap_hva notifier backend 2018-09-07 15:06:02 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Add file patterns for ipmi device tree bindings 2018-09-18 16:16:46 -05:00
Makefile Linux 4.19-rc4 2018-09-16 11:52:37 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.
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.