coresight: tmc-etf: Fix global-out-of-bounds in tmc_update_etf_buffer()
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
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 ==================================================================
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.14 and later | 4.19.198, 5.4.133, 5.10.51, 5.12.18, 5.13.3, 5.14 | Patch available | CNA |
- Linux VendorLinux Affected 4.14 and later Fixed in 4.19.198, 5.4.133, 5.10.51, 5.12.18, 5.13.3, 5.14 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.14 to before 4.19.198; 4.20 to before 5.4.133; 5.5 to before 5.10.51; 5.11 to before 5.12.18; 5.13 to before 5.13.3 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.14 to before 4.19.198; 4.20 to before 5.4.133; 5.5 to before 5.10.51; 5.11 to before 5.12.18; 5.13 to before 5.13.3 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.19.198, 5.4.133, 5.10.51, 5.12.18, 5.13.3, 5.14
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-47346
- 2026-10-03 Alias added: GHSA-3hw4-pvhh-9qcq
References
Patch 6
- https://git.kernel.org/stable/c/04bd77ef4f4d9fc6102023b85f4590fc2130aac5
- https://git.kernel.org/stable/c/ef0a06acc6b16388640ad367eedfa2a17f1945db
- https://git.kernel.org/stable/c/35c1c4bd2d59ad734129d4e232af9d1098023918
- https://git.kernel.org/stable/c/733d4d95c0101d5f277b8e4910411d016e49a9dc
- https://git.kernel.org/stable/c/0115687be7b13993066aef602253a53d55f5b11f
- https://git.kernel.org/stable/c/5fae8a946ac2df879caf3f79a193d4766d00239b
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2021-47346 · CVE Program
- CVE-2021-47346 · NVD
- FIRST EPSS
- GHSA-3hw4-pvhh-9qcq · GitHub Advisory Database · CC BY 4.0
- CVE-2021-47346 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences