{"cve":"CVE-2021-47428","nvd":{"published":"2024-05-21T15:15:28.210","modified":"2026-06-17T04:17:26.927","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/64s: fix program check interrupt emergency stack path\n\nEmergency stack path was jumping into a 3: label inside the\n__GEN_COMMON_BODY macro for the normal path after it had finished,\nrather than jumping over it. By a small miracle this is the correct\nplace to build up a new interrupt frame with the existing stack\npointer, so things basically worked okay with an added weird looking\n700 trap frame on top (which had the wrong ->nip so it didn't decode\nbug messages either).\n\nFix this by avoiding using numeric labels when jumping over non-trivial\nmacros.\n\nBefore:\n\n LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV\n Modules linked in:\n CPU: 0 PID: 88 Comm: sh Not tainted 5.15.0-rc2-00034-ge057cdade6e5 #2637\n NIP:  7265677368657265 LR: c00000000006c0c8 CTR: c0000000000097f0\n REGS: c0000000fffb3a50 TRAP: 0700   Not tainted\n MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 00000700  XER: 20040000\n CFAR: c0000000000098b0 IRQMASK: 0\n GPR00: c00000000006c964 c0000000fffb3cf0 c000000001513800 0000000000000000\n GPR04: 0000000048ab0778 0000000042000000 0000000000000000 0000000000001299\n GPR08: 000001e447c718ec 0000000022424282 0000000000002710 c00000000006bee8\n GPR12: 9000000000009033 c0000000016b0000 00000000000000b0 0000000000000001\n GPR16: 0000000000000000 0000000000000002 0000000000000000 0000000000000ff8\n GPR20: 0000000000001fff 0000000000000007 0000000000000080 00007fff89d90158\n GPR24: 0000000002000000 0000000002000000 0000000000000255 0000000000000300\n GPR28: c000000001270000 0000000042000000 0000000048ab0778 c000000080647e80\n NIP [7265677368657265] 0x7265677368657265\n LR [c00000000006c0c8] ___do_page_fault+0x3f8/0xb10\n Call Trace:\n [c0000000fffb3cf0] [c00000000000bdac] soft_nmi_common+0x13c/0x1d0 (unreliable)\n --- interrupt: 700 at decrementer_common_virt+0xb8/0x230\n NIP:  c0000000000098b8 LR: c00000000006c0c8 CTR: c0000000000097f0\n REGS: c0000000fffb3d60 TRAP: 0700   Not tainted\n MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 22424282  XER: 20040000\n CFAR: c0000000000098b0 IRQMASK: 0\n GPR00: c00000000006c964 0000000000002400 c000000001513800 0000000000000000\n GPR04: 0000000048ab0778 0000000042000000 0000000000000000 0000000000001299\n GPR08: 000001e447c718ec 0000000022424282 0000000000002710 c00000000006bee8\n GPR12: 9000000000009033 c0000000016b0000 00000000000000b0 0000000000000001\n GPR16: 0000000000000000 0000000000000002 0000000000000000 0000000000000ff8\n GPR20: 0000000000001fff 0000000000000007 0000000000000080 00007fff89d90158\n GPR24: 0000000002000000 0000000002000000 0000000000000255 0000000000000300\n GPR28: c000000001270000 0000000042000000 0000000048ab0778 c000000080647e80\n NIP [c0000000000098b8] decrementer_common_virt+0xb8/0x230\n LR [c00000000006c0c8] ___do_page_fault+0x3f8/0xb10\n --- interrupt: 700\n Instruction dump:\n XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX\n XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX\n ---[ end trace 6d28218e0cc3c949 ]---\n\nAfter:\n\n ------------[ cut here ]------------\n kernel BUG at arch/powerpc/kernel/exceptions-64s.S:491!\n Oops: Exception in kernel mode, sig: 5 [#1]\n LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV\n Modules linked in:\n CPU: 0 PID: 88 Comm: login Not tainted 5.15.0-rc2-00034-ge057cdade6e5-dirty #2638\n NIP:  c0000000000098b8 LR: c00000000006bf04 CTR: c0000000000097f0\n REGS: c0000000fffb3d60 TRAP: 0700   Not tainted\n MSR:  9000000000021031 <SF,HV,ME,IR,DR,LE>  CR: 24482227  XER: 00040000\n CFAR: c0000000000098b0 IRQMASK: 0\n GPR00: c00000000006bf04 0000000000002400 c000000001513800 c000000001271868\n GPR04: 00000000100f0d29 0000000042000000 0000000000000007 0000000000000009\n GPR08: 00000000100f0d29 0000000024482227 0000000000002710 c000000000181b3c\n GPR12: 9000000000009033 c0000000016b0000 00000000100f0d29 c000000005b22f00\n GPR16: 00000000ffff0000 0000000000000001 0000000000000009 00000000100eed90\n GPR20: 00000000100eed90 00000\n---truncated---","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/3e607dc4df180b72a38e75030cb0f94d12808712","https://git.kernel.org/stable/c/411b38fe68ba20a8bbe724b0939762c3f16e16ca","https://git.kernel.org/stable/c/c835b3d1d6362b4a4ebb192da7e7fd27a0a45d01","https://git.kernel.org/stable/c/3e607dc4df180b72a38e75030cb0f94d12808712","https://git.kernel.org/stable/c/411b38fe68ba20a8bbe724b0939762c3f16e16ca"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47428","score":0.00222,"percentile":0.12888,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}