CVE-2021-47346 json
coresight: tmc-etf: Fix global-out-of-bounds in tmc_update_etf_buffer()
published 2024-05-21 2 y ago modified 2026-08-05 3 mo ago also EUVD-2021-34351
- cvss
- 7.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 16%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
coresight: tmc-etf: Fix global-out-of-bounds in tmc_update_etf_buffer()
commit 6f755e85c332 ("coresight: Add helper for inserting synchronization packets") removed trailing '\0' from barrier_pkt array and updated the call sites like etb_update_buffer() to have proper checks for barrier_pkt size before read but missed updating tmc_update_etf_buffer() which still reads barrier_pkt past the array size resulting in KASAN out-of-bounds bug. Fix this by adding a check for barrier_pkt size before accessing like it is done in etb_update_buffer().
BUG: KASAN: global-out-of-bounds in tmc_update_etf_buffer+0x4b8/0x698 Read of size 4 at addr ffffffd05b7d1030 by task perf/2629
Call trace: dump_backtrace+0x0/0x27c show_stack+0x20/0x2c dump_stack+0x11c/0x188 print_address_description+0x3c/0x4a4 __kasan_report+0x140/0x164 kasan_report+0x10/0x18 __asan_report_load4_noabort+0x1c/0x24 tmc_update_etf_buffer+0x4b8/0x698 etm_event_stop+0x248/0x2d8 etm_event_del+0x20/0x2c event_sched_out+0x214/0x6f0 group_sched_out+0xd0/0x270 ctx_sched_out+0x2ec/0x518 __perf_event_task_sched_out+0x4fc/0xe6c __schedule+0x1094/0x16a0 preempt_schedule_irq+0x88/0x170 arm64_preempt_schedule_irq+0xf0/0x18c el1_irq+0xe8/0x180 perf_event_exec+0x4d8/0x56c setup_new_exec+0x204/0x400 load_elf_binary+0x72c/0x18c0 search_binary_handler+0x13c/0x420 load_script+0x500/0x6c4 search_binary_handler+0x13c/0x420 exec_binprm+0x118/0x654 __do_execve_file+0x77c/0xba4 __arm64_compat_sys_execve+0x98/0xac el0_svc_common+0x1f8/0x5e0 el0_svc_compat_handler+0x84/0xb0 el0_svc_compat+0x10/0x50
The buggy address belongs to the variable: barrier_pkt+0x10/0x40
Memory state around the buggy address: ffffffd05b7d0f00: fa fa fa fa 04 fa fa fa fa fa fa fa 00 00 00 00 ffffffd05b7d0f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffffd05b7d1000: 00 00 00 00 00 00 fa fa fa fa fa fa 00 00 00 03 ^ ffffffd05b7d1080: fa fa fa fa 00 02 fa fa fa fa fa fa 03 fa fa fa ffffffd05b7d1100: fa fa fa fa 00 00 00 00 05 fa fa fa fa fa fa fa ==================================================================
Patch / fix
- Linux Linux 4.19.198, 5.4.133, 5.10.51, 5.12.18, 5.13.3, 5.14
- linux Debian 14, Debian 13, Debian 12 5.14.6-1
debian advisories DEBIAN-CVE-2021-47346
- linux Ubuntu 18.04 LTS 4.15.0-156.163
- linux Ubuntu 20.04 LTS 5.4.0-84.94
- linux-aws Ubuntu 18.04 LTS 4.15.0-1111.118
- linux-aws Ubuntu 20.04 LTS 5.4.0-1056.59
- linux-gcp Ubuntu 20.04 LTS 5.4.0-1052.56
- linux-kvm Ubuntu 18.04 LTS 4.15.0-1099.101
- linux-kvm Ubuntu 20.04 LTS 5.4.0-1046.48
- linux-azure Ubuntu 20.04 LTS 5.4.0-1058.60
ubuntu advisories UBUNTU-CVE-2021-47346
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- git.kernel.org/stable/c/04bd77ef4f4d9fc6102023b85f4590fc2130aac5 commit
- git.kernel.org/stable/c/ef0a06acc6b16388640ad367eedfa2a17f1945db commit
- git.kernel.org/stable/c/35c1c4bd2d59ad734129d4e232af9d1098023918 commit
- git.kernel.org/stable/c/733d4d95c0101d5f277b8e4910411d016e49a9dc commit
- git.kernel.org/stable/c/0115687be7b13993066aef602253a53d55f5b11f commit
- git.kernel.org/stable/c/5fae8a946ac2df879caf3f79a193d4766d00239b commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2021-47346 updated cvss 5.1
kernel: coresight: tmc-etf: Fix global-out-of-bounds in tmc_update_etf_buffer()
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| NVD | 3.1 | 7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
Affected products
- Linux Linux
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
- Technology feeds
References
-
git.kernel.org
/stable/c/04bd77ef4f4d9fc6102023b85f4590fc2130aac5
patch
-
git.kernel.org
/stable/c/ef0a06acc6b16388640ad367eedfa2a17f1945db
patch
-
git.kernel.org
/stable/c/35c1c4bd2d59ad734129d4e232af9d1098023918
patch
-
git.kernel.org
/stable/c/733d4d95c0101d5f277b8e4910411d016e49a9dc
patch
-
git.kernel.org
/stable/c/0115687be7b13993066aef602253a53d55f5b11f
patch
-
git.kernel.org
/stable/c/5fae8a946ac2df879caf3f79a193d4766d00239b
patch
Sources
- CVE List CVE-2021-47346
- NVD CVE-2021-47346
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