cve-2021-47608
Vulnerability from cvelistv5
Published
2024-06-19 14:54
Modified
2024-11-04 12:09
Severity ?
Summary
bpf: Fix kernel address leakage in atomic fetch
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/423628125a484538111c2c6d9bb1588eb086053bPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7d3baf0afa3aa9102d6a521a8e4c41888bb79882Patch
Impacted products
Vendor Product Version
Linux Linux Version: 5.12
Show details on NVD website

To clipboard 

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    "datePublished": "2024-06-19T14:54:06.388Z",
    "dateReserved": "2024-05-24T15:11:00.737Z",
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BPF_READ tambi\u00e9n incluy\u00f3 una verificaci\u00f3n en check_stack_read_fixed_off() que rechaza el programa si la ranura de la pila es de __is_pointer_value() si dst_regno \u0026lt; 0. Esto \u00faltimo es para distinguir si estamos tratando con un derrame/llenado de pila regular o alguna operaci\u00f3n aritm\u00e9tica que no est\u00e1 permitido en valores no escalares, consulte tambi\u00e9n 6e7e63cbb023 (\\\"bpf: Prohibir XADD en punteros dispersos para usuarios sin privilegios\\\") para obtener m\u00e1s contexto sobre check_mem_access() y su manejo del valor del marcador de posici\u00f3n -1. 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