diff options
| -rw-r--r-- | sys/src/libc/port/pool.c | 58 |
1 files changed, 28 insertions, 30 deletions
diff --git a/sys/src/libc/port/pool.c b/sys/src/libc/port/pool.c index 915fca3f1..0bbe89a22 100644 --- a/sys/src/libc/port/pool.c +++ b/sys/src/libc/port/pool.c @@ -159,7 +159,6 @@ static void poolnewarena(Pool*, ulong); static void* poolreallocl(Pool*, void*, ulong); static Free* treedelete(Free*, Free*); static Free* treeinsert(Free*, Free*); -static Free* treelookup(Free*, ulong); static Free* treelookupgt(Free*, ulong); /* @@ -230,30 +229,21 @@ checktree(Free *t, int a, int b) static Free** ltreewalk(Free **t, ulong size) { - assert(t != nil /* ltreewalk */); + Free *f; for(;;) { - if(*t == nil) + f = *t; + if(f == nil || f->magic != FREE_MAGIC) return t; - - assert((*t)->magic == FREE_MAGIC); - - if(size == (*t)->size) + if(size == f->size) return t; - if(size < (*t)->size) - t = &(*t)->left; + if(size < f->size) + t = &f->left; else - t = &(*t)->right; + t = &f->right; } } -/* treelookup: find node in tree with size == size */ -static Free* -treelookup(Free *t, ulong size) -{ - return *ltreewalk(&t, size); -} - /* treeinsert: insert node into tree */ static Free* treeinsert(Free *tree, Free *node) @@ -263,11 +253,11 @@ treeinsert(Free *tree, Free *node) assert(node != nil /* treeinsert */); loc = ltreewalk(&tree, node->size); - if(*loc == nil) { + repl = *loc; + if(repl == nil || repl->magic != FREE_MAGIC) { node->left = nil; node->right = nil; } else { /* replace existing node */ - repl = *loc; node->left = repl->left; node->right = repl->right; } @@ -284,7 +274,8 @@ treedelete(Free *tree, Free *node) assert(node != nil /* treedelete */); loc = ltreewalk(&tree, node->size); - assert(*loc == node); + if(*loc != node || node->magic != FREE_MAGIC) + return tree; /* free nodes corrupted */ if(node->left == nil) *loc = node->right; @@ -300,7 +291,6 @@ treedelete(Free *tree, Free *node) succ->right = node->right; *loc = succ; } - node->left = node->right = Poison; return tree; } @@ -313,7 +303,7 @@ treelookupgt(Free *t, ulong size) lastgood = nil; for(;;) { - if(t == nil) + if(t == nil || t->magic != FREE_MAGIC) return lastgood; if(size == t->size) return t; @@ -387,6 +377,11 @@ pooladd(Pool *p, Alloc *anode) node->magic = FREE_MAGIC; parent = ltreewalk(&p->freeroot, node->size); olst = *parent; + if(olst != nil && olst->magic != FREE_MAGIC){ + /* corruption of free nodes */ + poolcheckl(p); + olst = *parent = nil; + } lst = listadd(olst, node); if(olst != lst) /* need to update tree */ *parent = treeinsert(*parent, lst); @@ -403,14 +398,17 @@ pooldel(Pool *p, Free *node) parent = ltreewalk(&p->freeroot, node->size); olst = *parent; - assert(olst != nil /* pooldel */); - - lst = listdelete(olst, node); - if(lst == nil) - *parent = treedelete(*parent, olst); - else if(lst != olst) - *parent = treeinsert(*parent, lst); - + if(olst == nil || olst->magic != FREE_MAGIC){ + /* corruption of free nodes */ + poolcheckl(p); + *parent = nil; + } else { + lst = listdelete(olst, node); + if(lst == nil) + *parent = treedelete(*parent, olst); + else if(lst != olst) + *parent = treeinsert(*parent, lst); + } node->left = node->right = Poison; p->curfree -= node->size; |