π Fix missing arena bounds check in obj_bump#26
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Added `obj_arena_end` tracking to `obj_arena_init` and checked if allocations exceed it in `obj_bump`, calling `unreachable()` if so. Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
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- Fix stray brace in kernel-root.in and remove dead thr_exit return - Add heap/obj_arena bounds checks (PRs #30, #26) - Harden malloc/calloc/realloc; replace strcpy with strlcpy; remove strcat (PRs #20, #18, #21, #28, #15) - Split nvme_pci_init, restore e1000_rx_poll, use FS_MAX_FILES constants (PRs #14, #17, #16) - Refresh context.md ponytail index after service-wrapper deletion
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Changes applied directly on main (rebased past shell.in extraction and service-wrapper deletion). Used panic() instead of unreachable()/assert() where the PRs referenced undefined helpers. |
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Merged to main in 22933b8. Changes applied directly on main (rebased past shell.in extraction and service-wrapper deletion). Used panic() instead of unreachable()/assert() where the PRs referenced undefined helpers. |
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π― What: Fixed a vulnerability in the
β οΈ Risk: Without a bounds check, excessive allocations could write past the end of the
obj_bumpobject arena bump allocator which lacked boundary checks, potentially allowing unbounded memory allocations.obj_arena, leading to buffer overflows, kernel data corruption, and potentially allowing arbitrary code execution or crashes (Denial of Service).π‘οΈ Solution: Introduced the
obj_arena_endvariable which tracks the upper bound of the object arena. Updatedobj_bumpto verify thatnextpointers do not surpassobj_arena_end. If the bound is exceeded,unreachable()is triggered, immediately halting execution and safely preventing exploitation of the buffer overflow.PR created automatically by Jules for task 11355866470254841318 started by @undivisible