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Linux Internals: How /proc/self/mem writes to unwritable memory (2021)

by Mark offlinemark.com published 2021-05-12

Introduction An obscure quirk of the /proc/*/mem pseudofile is its “punch through” semantics. Writes performed through this file will succeed even if the destination virtual memory is marked unwritable. In fact, this behavior is intentional and actively used by projects such as the Julia JIT compiler and rr debugger…
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Systems & PerformanceSecurity & Privacy2026

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Mar 8, 2026Linux Internals: How /proc/self/mem writes to unwritable memory (2021) by medbar12929

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