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SLL triage step 2: use safe tls_sll_pop for classes >=4 in alloc fast path; add optional safe header mode for tls_sll_push (HAKMEM_TINY_SLL_SAFEHEADER). Shared SS stable with SLL C0..C4; class5 hotpath causes crash, can be bypassed with HAKMEM_TINY_HOTPATH_CLASS5=0.

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Moe Charm (CI)
2025-11-14 01:29:55 +09:00
parent 3b05d0f048
commit e573c98a5e
2 changed files with 38 additions and 13 deletions
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24
core/box/tls_sll_box.h
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@ -113,14 +113,28 @@ static inline bool tls_sll_push(int class_idx, void* ptr, uint32_t capacity)
}
#if HAKMEM_TINY_HEADER_CLASSIDX
// Restore header defensively for header classes (class != 0,7 use header byte).
// Header handling for header classes (class != 0,7).
// Safe mode (HAKMEM_TINY_SLL_SAFEHEADER=1): never overwrite header; reject on magic mismatch.
// Default mode: restore expected header.
if (class_idx != 0 && class_idx != 7) {
static int g_sll_safehdr = -1;
if (__builtin_expect(g_sll_safehdr == -1, 0)) {
const char* e = getenv("HAKMEM_TINY_SLL_SAFEHEADER");
g_sll_safehdr = (e && *e && *e != '0') ? 1 : 0;
}
uint8_t* b = (uint8_t*)ptr;
uint8_t expected = (uint8_t)(HEADER_MAGIC | (class_idx & HEADER_CLASS_MASK));
// Always set; any mismatch is effectively healed here.
PTR_TRACK_TLS_PUSH(ptr, class_idx);
PTR_TRACK_HEADER_WRITE(ptr, expected);
*b = expected;
if (g_sll_safehdr) {
uint8_t got = *b;
if ((got & 0xF0u) != HEADER_MAGIC) {
// Reject push silently (fall back to slow path at caller)
return false;
}
} else {
PTR_TRACK_TLS_PUSH(ptr, class_idx);
PTR_TRACK_HEADER_WRITE(ptr, expected);
*b = expected;
}
}
#endif