CVE-2022-50647 — RISC-V: Make port I/O string accessors actually work
In the Linux kernel, the following vulnerability has been resolved: RISC-V: Make port I/O string accessors actually work Fix port I/O string accessors such as `insb', `outsb', etc. which use the physical PCI port I/O address rather than the corresponding memory mapping to get at the requested location, which in turn breaks at least accesses made by our parport driver to a PCIe parallel port such as: PCI parallel port detected: 1415:c118, I/O at 0x1000(0x1008), IRQ 20 parport0: PC-style at 0x1000 (0x1008), irq 20, using FIFO [PCSPP,TRISTATE,COMPAT,EPP,ECP] causing a memory access fault: Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000001008 Oops [#1] Modules linked in: CPU: 1 PID: 350 Comm: cat Not tainted 6.0.0-rc2-00283-g10d4879f9ef0-dirty #23 Hardware name: SiFive HiFive Unmatched A00 (DT) epc : parport_pc_fifo_write_block_pio+0x266/0x416 ra : parport_pc_fifo_write_block_pio+0xb4/0x416 epc : ffffffff80542c3e ra : ffffffff80542a8c sp : ffffffd88899fc60 gp : ffffffff80fa2700 tp : ffffffd882b1e900 t0 : ffffffd883d0b000 t1 : ffffffffff000002 t2 : 4646393043330a38 s0 : ffffffd88899fcf0 s1 : 0000000000001000 a0 : 0000000000000010 a1 : 0000000000000000 a2 : ffffffd883d0a010 a3 : 0000000000000023 a4 : 00000000ffff8fbb a5 : ffffffd883d0a001 a6 : 0000000100000000 a7 : ffffffc800000000 s2 : ffffffffff000002 s3 : ffffffff80d28880 s4 : ffffffff80fa1f50 s5 : 0000000000001008 s6 : 0000000000000008 s7 : ffffffd883d0a000 s8 : 0004000000000000 s9 : ffffffff80dc1d80 s10: ffffffd8807e4000 s11: 0000000000000000 t3 : 00000000000000ff t4 : 393044410a303930 t5 : 0000000000001000 t6 : 0000000000040000 status: 0000000200000120 badaddr: 0000000000001008 cause: 000000000000000f [<ffffffff80543212>] parport_pc_compat_write_block_pio+0xfe/0x200 [<ffffffff8053bbc0>] parport_write+0x46/0xf8 [<ffffffff8050530e>] lp_write+0x158/0x2d2 [<ffffffff80185716>] vfs_write+0x8e/0x2c2 [<ffffffff80185a74>] ksys_write+0x52/0xc2 [<ffffffff80185af2>] sys_write+0xe/0x16 [<ffffffff80003770>] ret_from_syscall+0x0/0x2 ---[ end trace 0000000000000000 ]--- For simplicity address the problem by adding PCI_IOBASE to the physical address requested in the respective wrapper macros only, observing that the raw accessors such as `__insb', `__outsb', etc. are not supposed to be used other than by said macros. Remove the cast to `long' that is no longer needed on `addr' now that it is used as an offset from PCI_IOBASE and add parentheses around `addr' needed for predictable evaluation in macro expansion. No need to make said adjustments in separate changes given that current code is gravely broken and does not ever work.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < 2c60db6869fe5213471fcf4fe5704dc29da8b5ee≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < 2ce9fab94b8db61f014e43ddf80dd1524ae6dff4≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < dc235db7b79a352d07d62e8757ad856dbf1564c1≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < 140b2b92dbefffa7f4f7211a1fd399a6e79e71c4≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < 1acee4616930fc07265cb8e539753a8062daa8e0≥ fab957c11efe2f405e08b9f0d080524bc2631428 and < 9cc205e3c17d5716da7ebb7fa0c985555e95d009version 4.15 | Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.21%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Deferred
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
6 on the record
- git.kernel.org/stable/c/dc235db7b79a352d07d62e8757ad856dbf1564c1
- git.kernel.org/stable/c/2ce9fab94b8db61f014e43ddf80dd1524ae6dff4
- git.kernel.org/stable/c/2c60db6869fe5213471fcf4fe5704dc29da8b5ee
- git.kernel.org/stable/c/9cc205e3c17d5716da7ebb7fa0c985555e95d009
- git.kernel.org/stable/c/1acee4616930fc07265cb8e539753a8062daa8e0
- git.kernel.org/stable/c/140b2b92dbefffa7f4f7211a1fd399a6e79e71c4
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 7h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 7h
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2022-50647 is "RISC-V: Make port I/O string accessors actually work", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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