From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Michael Neuling <mikey@neuling.org>,
Nicholas Piggin <npiggin@gmail.com>,
Christophe Leroy <christophe.leroy@c-s.fr>,
Michael Ellerman <mpe@ellerman.id.au>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.9 13/76] powerpc: Avoid code patching freed init sections
Date: Mon, 15 Apr 2019 20:43:37 +0200 [thread overview]
Message-ID: <20190415183711.514716690@linuxfoundation.org> (raw)
In-Reply-To: <20190415183707.712011689@linuxfoundation.org>
commit 51c3c62b58b357e8d35e4cc32f7b4ec907426fe3 upstream.
This stops us from doing code patching in init sections after they've
been freed.
In this chain:
kvm_guest_init() ->
kvm_use_magic_page() ->
fault_in_pages_readable() ->
__get_user() ->
__get_user_nocheck() ->
barrier_nospec();
We have a code patching location at barrier_nospec() and
kvm_guest_init() is an init function. This whole chain gets inlined,
so when we free the init section (hence kvm_guest_init()), this code
goes away and hence should no longer be patched.
We seen this as userspace memory corruption when using a memory
checker while doing partition migration testing on powervm (this
starts the code patching post migration via
/sys/kernel/mobility/migration). In theory, it could also happen when
using /sys/kernel/debug/powerpc/barrier_nospec.
Cc: stable@vger.kernel.org # 4.13+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/include/asm/setup.h | 1 +
arch/powerpc/lib/code-patching.c | 8 ++++++++
arch/powerpc/mm/mem.c | 2 ++
3 files changed, 11 insertions(+)
diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 703ddf752516..709f4e739ae8 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -8,6 +8,7 @@ extern void ppc_printk_progress(char *s, unsigned short hex);
extern unsigned int rtas_data;
extern unsigned long long memory_limit;
+extern bool init_mem_is_free;
extern unsigned long klimit;
extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 753d591f1b52..c77c486fbf24 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -14,12 +14,20 @@
#include <asm/page.h>
#include <asm/code-patching.h>
#include <asm/uaccess.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
int patch_instruction(unsigned int *addr, unsigned int instr)
{
int err;
+ /* Make sure we aren't patching a freed init section */
+ if (init_mem_is_free && init_section_contains(addr, 4)) {
+ pr_debug("Skipping init section patching addr: 0x%px\n", addr);
+ return 0;
+ }
+
__put_user_size(instr, addr, 4, err);
if (err)
return err;
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 5f844337de21..1e93dbc88e80 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -62,6 +62,7 @@
#endif
unsigned long long memory_limit;
+bool init_mem_is_free;
#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
@@ -396,6 +397,7 @@ void __init mem_init(void)
void free_initmem(void)
{
ppc_md.progress = ppc_printk_progress;
+ init_mem_is_free = true;
free_initmem_default(POISON_FREE_INITMEM);
}
--
2.19.1
next prev parent reply other threads:[~2019-04-15 18:51 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-15 18:43 [PATCH 4.9 00/76] 4.9.169-stable review Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 01/76] x86/power: Fix some ordering bugs in __restore_processor_context() Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 02/76] x86/power/64: Use struct desc_ptr for the IDT in struct saved_context Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 03/76] x86/power/32: Move SYSENTER MSR restoration to fix_processor_context() Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 04/76] x86/power: Make restore_processor_context() sane Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 05/76] powerpc/tm: Limit TM code inside PPC_TRANSACTIONAL_MEM Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 06/76] kbuild: clang: choose GCC_TOOLCHAIN_DIR not on LD Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 07/76] x86: vdso: Use $LD instead of $CC to link Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 08/76] x86/vdso: Drop implicit common-page-size linker flag Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 09/76] lib/string.c: implement a basic bcmp Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 10/76] powerpc: Fix invalid use of register expressions Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 11/76] powerpc/64s: Add barrier_nospec Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 12/76] powerpc/64s: Add support for ori barrier_nospec patching Greg Kroah-Hartman
2019-04-15 18:43 ` Greg Kroah-Hartman [this message]
2019-04-15 18:43 ` [PATCH 4.9 14/76] powerpc/64s: Patch barrier_nospec in modules Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 15/76] powerpc/64s: Enable barrier_nospec based on firmware settings Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 16/76] powerpc: Use barrier_nospec in copy_from_user() Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 17/76] powerpc/64: Use barrier_nospec in syscall entry Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 18/76] powerpc/64s: Enhance the information in cpu_show_spectre_v1() Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 19/76] powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2 Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 20/76] powerpc/64: Disable the speculation barrier from the command line Greg Kroah-Hartman
2019-04-16 15:43 ` Diana Madalina Craciun
2019-04-16 18:46 ` Greg Kroah-Hartman
2019-04-17 8:41 ` Michael Ellerman
2019-04-15 18:43 ` [PATCH 4.9 21/76] powerpc/64: Make stf barrier PPC_BOOK3S_64 specific Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 22/76] powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 23/76] powerpc/64: Call setup_barrier_nospec() from setup_arch() Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 24/76] powerpc/64: Make meltdown reporting Book3S 64 specific Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 25/76] powerpc/fsl: Add barrier_nospec implementation for NXP PowerPC Book3E Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 26/76] powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 27/76] powerpc/asm: Add a patch_site macro & helpers for patching instructions Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 28/76] powerpc/64s: Add new security feature flags for count cache flush Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 29/76] powerpc/64s: Add support for software " Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 30/76] powerpc/pseries: Query hypervisor for count cache flush settings Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 31/76] powerpc/powernv: Query firmware " Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 32/76] powerpc/fsl: Add infrastructure to fixup branch predictor flush Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 33/76] powerpc/fsl: Add macro to flush the branch predictor Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 34/76] powerpc/fsl: Fix spectre_v2 mitigations reporting Greg Kroah-Hartman
2019-04-15 18:43 ` [PATCH 4.9 35/76] powerpc/fsl: Emulate SPRN_BUCSR register Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 36/76] powerpc/fsl: Add nospectre_v2 command line argument Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 37/76] powerpc/fsl: Flush the branch predictor at each kernel entry (64bit) Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 38/76] powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit) Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 39/76] powerpc/fsl: Flush branch predictor when entering KVM Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 40/76] powerpc/fsl: Enable runtime patching if nospectre_v2 boot arg is used Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 41/76] powerpc/fsl: Update Spectre v2 reporting Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 42/76] powerpc/fsl: Fixed warning: orphan section `__btb_flush_fixup Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 43/76] powerpc/fsl: Fix the flush of branch predictor Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 44/76] powerpc/security: Fix spectre_v2 reporting Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 45/76] arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 46/76] tty: mark Siemens R3964 line discipline as BROKEN Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 47/76] tty: ldisc: add sysctl to prevent autoloading of ldiscs Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 48/76] ipv6: Fix dangling pointer when ipv6 fragment Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 49/76] ipv6: sit: reset ip header pointer in ipip6_rcv Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 50/76] kcm: switch order of device registration to fix a crash Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 51/76] net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock() Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 52/76] openvswitch: fix flow actions reallocation Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 53/76] qmi_wwan: add Olicard 600 Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 54/76] sctp: initialize _pad of sockaddr_in before copying to user memory Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 55/76] tcp: Ensure DCTCP reacts to losses Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 56/76] vrf: check accept_source_route on the original netdevice Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 57/76] bnxt_en: Reset device on RX buffer errors Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 58/76] bnxt_en: Improve RX consumer index validity check Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 59/76] net/mlx5e: Add a lock on tir list Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 60/76] netns: provide pure entropy for net_hash_mix() Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 61/76] net: ethtool: not call vzalloc for zero sized memory request Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 62/76] ip6_tunnel: Match to ARPHRD_TUNNEL6 for dev type Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 63/76] ALSA: seq: Fix OOB-reads from strlcpy Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 64/76] parisc: Detect QEMU earlier in boot process Greg Kroah-Hartman
2019-04-16 13:50 ` Helge Deller
2019-04-16 14:23 ` Greg Kroah-Hartman
2019-04-16 15:00 ` Helge Deller
2019-04-16 18:03 ` Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 65/76] include/linux/bitrev.h: fix constant bitrev Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 66/76] ASoC: fsl_esai: fix channel swap issue when stream starts Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 67/76] Btrfs: do not allow trimming when a fs is mounted with the nologreplay option Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 68/76] block: do not leak memory in bio_copy_user_iov() Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 69/76] genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent() Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 70/76] virtio: Honour may_reduce_num in vring_create_virtqueue Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 71/76] ARM: dts: at91: Fix typo in ISC_D0 on PC9 Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 72/76] arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value Greg Kroah-Hartman
2019-04-15 22:01 ` Nathan Chancellor
2019-04-16 9:00 ` Greg Kroah-Hartman
2019-04-16 16:47 ` Nathan Chancellor
2019-04-17 6:15 ` Greg Kroah-Hartman
2019-04-17 6:41 ` Nathan Chancellor
2019-04-17 6:47 ` Greg Kroah-Hartman
2019-04-16 9:13 ` Will Deacon
2019-04-16 16:49 ` Nathan Chancellor
2019-04-15 18:44 ` [PATCH 4.9 73/76] xen: Prevent buffer overflow in privcmd ioctl Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 74/76] sched/fair: Do not re-read ->h_load_next during hierarchical load calculation Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 75/76] xtensa: fix return_address Greg Kroah-Hartman
2019-04-15 18:44 ` [PATCH 4.9 76/76] PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller Greg Kroah-Hartman
2019-04-16 0:44 ` [PATCH 4.9 00/76] 4.9.169-stable review kernelci.org bot
2019-04-16 4:06 ` Naresh Kamboju
2019-04-16 10:33 ` Jon Hunter
2019-04-16 13:12 ` Guenter Roeck
2019-04-16 16:29 ` Guenter Roeck
2019-04-16 18:46 ` Greg Kroah-Hartman
2019-04-16 20:19 ` Guenter Roeck
2019-04-16 20:27 ` Greg Kroah-Hartman
2019-04-16 21:39 ` shuah
2019-04-16 22:05 ` Bharath Vedartham
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190415183711.514716690@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=christophe.leroy@c-s.fr \
--cc=linux-kernel@vger.kernel.org \
--cc=mikey@neuling.org \
--cc=mpe@ellerman.id.au \
--cc=npiggin@gmail.com \
--cc=sashal@kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).