From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>,
Steven Rostedt <rostedt@goodmis.org>
Subject: [PATCH 5.10 03/43] tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
Date: Mon, 10 Jan 2022 08:23:00 +0100 [thread overview]
Message-ID: <20220110071817.449633154@linuxfoundation.org> (raw)
In-Reply-To: <20220110071817.337619922@linuxfoundation.org>
From: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
commit 823e670f7ed616d0ce993075c8afe0217885f79d upstream.
With the new osnoise tracer, we are seeing the below splat:
Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0)
BUG: Unable to handle kernel data access on read at 0xc7d880000
Faulting instruction address: 0xc0000000002ffa10
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
...
NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0
LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0
Call Trace:
[c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable)
[c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90
[c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290
[c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710
[c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130
[c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270
[c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180
[c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278
osnoise tracer on ppc64le is triggering osnoise_taint() for negative
duration in get_int_safe_duration() called from
trace_sched_switch_callback()->thread_exit().
The problem though is that the check for a valid trace_percpu_buffer is
incorrect in get_trace_buf(). The check is being done after calculating
the pointer for the current cpu, rather than on the main percpu pointer.
Fix the check to be against trace_percpu_buffer.
Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes: e2ace001176dc9 ("tracing: Choose static tp_printk buffer by explicit nesting count")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/trace/trace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3144,7 +3144,7 @@ static char *get_trace_buf(void)
{
struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer);
- if (!buffer || buffer->nesting >= 4)
+ if (!trace_percpu_buffer || buffer->nesting >= 4)
return NULL;
buffer->nesting++;
next prev parent reply other threads:[~2022-01-10 7:31 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-10 7:22 [PATCH 5.10 00/43] 5.10.91-rc1 review Greg Kroah-Hartman
2022-01-10 7:22 ` [PATCH 5.10 01/43] f2fs: quota: fix potential deadlock Greg Kroah-Hartman
2022-01-10 7:22 ` [PATCH 5.10 02/43] selftests: x86: fix [-Wstringop-overread] warn in test_process_vm_readv() Greg Kroah-Hartman
2022-01-10 7:23 ` Greg Kroah-Hartman [this message]
2022-01-10 7:23 ` [PATCH 5.10 04/43] tracing: Tag trace_percpu_buffer as a percpu pointer Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 05/43] ieee802154: atusb: fix uninit value in atusb_set_extended_addr Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 06/43] i40e: Fix to not show opcode msg on unsuccessful VF MAC change Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 07/43] iavf: Fix limit of total number of queues to active queues of VF Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 08/43] RDMA/core: Dont infoleak GRH fields Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 09/43] netrom: fix copying in user data in nr_setsockopt Greg Kroah-Hartman
2022-01-10 10:07 ` Pavel Machek
2022-01-10 10:14 ` Dan Carpenter
2022-01-10 7:23 ` [PATCH 5.10 10/43] RDMA/uverbs: Check for null return of kmalloc_array Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 11/43] mac80211: initialize variable have_higher_than_11mbit Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 12/43] sfc: The RX page_ring is optional Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 13/43] i40e: fix use-after-free in i40e_sync_filters_subtask() Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 14/43] i40e: Fix for displaying message regarding NVM version Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 15/43] i40e: Fix incorrect netdevs real number of RX/TX queues Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 16/43] ftrace/samples: Add missing prototypes direct functions Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 17/43] ipv4: Check attribute length for RTA_GATEWAY in multipath route Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 18/43] ipv4: Check attribute length for RTA_FLOW " Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 19/43] ipv6: Check attribute length for RTA_GATEWAY " Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 20/43] ipv6: Check attribute length for RTA_GATEWAY when deleting " Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 21/43] lwtunnel: Validate RTA_ENCAP_TYPE attribute length Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 22/43] batman-adv: mcast: dont send link-local multicast to mcast routers Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 23/43] sch_qfq: prevent shift-out-of-bounds in qfq_init_qdisc Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 24/43] net: ena: Fix undefined state when tx request id is out of bounds Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 25/43] net: ena: Fix error handling when calculating max IO queues number Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 26/43] xfs: map unwritten blocks in XFS_IOC_{ALLOC,FREE}SP just like fallocate Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 27/43] power: supply: core: Break capacity loop Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 28/43] power: reset: ltc2952: Fix use of floating point literals Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 29/43] rndis_host: support Hytera digital radios Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 30/43] phonet: refcount leak in pep_sock_accep Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 31/43] power: bq25890: Enable continuous conversion for ADC at charging Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 32/43] ipv6: Continue processing multipath route even if gateway attribute is invalid Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 33/43] ipv6: Do cleanup if attribute validation fails in multipath route Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 34/43] usb: mtu3: fix interval value for intr and isoc Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 35/43] scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown() Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 36/43] ip6_vti: initialize __ip6_tnl_parm struct in vti6_siocdevprivate Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 37/43] net: udp: fix alignment problem in udp4_seq_show() Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 38/43] atlantic: Fix buff_ring OOB in aq_ring_rx_clean Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 39/43] mISDN: change function names to avoid conflicts Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 40/43] drm/amd/display: Added power down for DCN10 Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 41/43] ipv6: raw: check passed optlen before reading Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 42/43] ARM: dts: gpio-ranges property is now required Greg Kroah-Hartman
2022-01-10 7:23 ` [PATCH 5.10 43/43] Input: zinitix - make sure the IRQ is allocated before it gets enabled Greg Kroah-Hartman
2022-01-10 11:49 ` [PATCH 5.10 00/43] 5.10.91-rc1 review Jon Hunter
2022-01-10 19:10 ` Fox Chen
2022-01-10 19:50 ` Florian Fainelli
2022-01-10 22:56 ` Shuah Khan
2022-01-10 23:50 ` Guenter Roeck
2022-01-11 3:34 ` Samuel Zou
2022-01-11 5:26 ` Naresh Kamboju
2022-01-11 12:37 ` Sudip Mukherjee
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=20220110071817.449633154@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=naveen.n.rao@linux.vnet.ibm.com \
--cc=rostedt@goodmis.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).