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A comment on Linear Address Spaces: Unsafe at any speed. Parent comment

Re:Linear Address Spaces: Unsafe at any speed by tliltocatl on Sunday January 04, 2026 @05:46PM (#46493184)
But that wouldn't protect against out-of boundary access (which is the whole point of segments), would it?
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Re:Linear Address Spaces: Unsafe at any speed by convolvatron on Monday January 05, 2026 @02:49PM (#46503820)
thats enforced by the VM hardware - we just shuffle the PTEs around to match the appropriate segment view
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Re:Linear Address Spaces: Unsafe at any speed by rep_lodsb on Tuesday January 06, 2026 @04:00AM (#46510162)
As long as it's a linear address space, adding/subtracting a large enough value to a pointer (array, stack) could still cross into another "segment".
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Re:Linear Address Spaces: Unsafe at any speed by convolvatron on Tuesday January 06, 2026 @09:06AM (#46512387)
but those wouldn't be mapped unless you have crossed a call gate that enabled them. the kernel call gate implementation changes the VM map (region visibility) accordingly
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