From 09f5e1635ae75de077c5307d02fdbefc4b0c7144 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sun, 31 Dec 2000 07:39:50 +0000 Subject: [PATCH] Update. 2000-12-28 Wolfram Gloger * malloc/malloc.c (MALLOC_COPY): Handle case if source and destination overlap. Assume dest is always below source if overlapping. --- ChangeLog | 6 ++++++ elf/dl-open.c | 15 +++++++-------- linuxthreads/ChangeLog | 5 +++++ linuxthreads/manager.c | 31 ++++++++++++++++--------------- malloc/malloc.c | 36 +++++++++++++++++++++--------------- 5 files changed, 55 insertions(+), 38 deletions(-) diff --git a/ChangeLog b/ChangeLog index 241e38b..297ab49 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2000-12-28 Wolfram Gloger + + * malloc/malloc.c (MALLOC_COPY): Handle case if source and + destination overlap. Assume dest is always below source if + overlapping. + 2000-12-30 Ulrich Drepper * elf/dl-close.c (_dl_close): We can ignore the NODELETE flag if the diff --git a/elf/dl-open.c b/elf/dl-open.c index d1ccfd4..0170d1c 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -269,10 +269,6 @@ dl_open_worker (void *a) /* Load that object's dependencies. */ _dl_map_object_deps (new, NULL, 0, 0); - /* Increment the open count for all dependencies. */ - for (i = 0; i < new->l_searchlist.r_nlist; ++i) - ++new->l_searchlist.r_list[i]->l_opencount; - /* So far, so good. Now check the versions. */ for (i = 0; i < new->l_searchlist.r_nlist; ++i) if (new->l_searchlist.r_list[i]->l_versions == NULL) @@ -321,6 +317,10 @@ dl_open_worker (void *a) l = l->l_prev; } + /* Increment the open count for all dependencies. */ + for (i = 0; i < new->l_searchlist.r_nlist; ++i) + ++new->l_searchlist.r_list[i]->l_opencount; + /* Run the initializer functions of new objects. */ _dl_init (new, __libc_argc, __libc_argv, __environ); @@ -399,11 +399,10 @@ _dl_open (const char *file, int mode, const void *caller) { int i; - /* Increment open counters for all objects which did not get - correctly loaded. */ + /* Increment open counters for all objects since this has + not happened yet. */ for (i = 0; i < args.map->l_searchlist.r_nlist; ++i) - if (args.map->l_searchlist.r_list[i]->l_opencount == 0) - args.map->l_searchlist.r_list[i]->l_opencount = 1; + ++args.map->l_searchlist.r_list[i]->l_opencount; _dl_close (args.map); } diff --git a/linuxthreads/ChangeLog b/linuxthreads/ChangeLog index 1760994..2bb9371 100644 --- a/linuxthreads/ChangeLog +++ b/linuxthreads/ChangeLog @@ -1,3 +1,8 @@ +2000-11-15 Wolfram Gloger + + * manager.c (pthread_free): [!FLOATING_STACKS]: Only remap the + stack to PROT_NONE, don't unmap it, avoiding collisions with malloc. + 2000-12-27 Andreas Jaeger * Examples/ex13.c: Make local functions static. diff --git a/linuxthreads/manager.c b/linuxthreads/manager.c index 37f4267..8442629 100644 --- a/linuxthreads/manager.c +++ b/linuxthreads/manager.c @@ -418,7 +418,7 @@ static int pthread_allocate_stack(const pthread_attr_t *attr, new_thread_bottom = (char *) map_addr + guardsize; new_thread = ((pthread_descr) (new_thread_bottom + stacksize)) - 1; -# else +# else /* !FLOATING_STACKS */ if (attr != NULL) { guardsize = page_roundup (attr->__guardsize, granularity); @@ -696,23 +696,24 @@ static void pthread_free(pthread_descr th) { size_t guardsize = th->p_guardsize; /* Free the stack and thread descriptor area */ -#ifdef NEED_SEPARATE_REGISTER_STACK char *guardaddr = th->p_guardaddr; - /* We unmap exactly what we mapped, in case there was something - else in the same region. Guardaddr is always set, eve if - guardsize is 0. This allows us to compute everything else. */ + /* Guardaddr is always set, even if guardsize is 0. This allows + us to compute everything else. */ size_t stacksize = (char *)(th+1) - guardaddr - guardsize; - /* Unmap the register stack, which is below guardaddr. */ - munmap((caddr_t)(guardaddr-stacksize), - 2 * stacksize + th->p_guardsize); +#ifdef NEED_SEPARATE_REGISTER_STACK + /* Take account of the register stack, which is below guardaddr. */ + guardaddr -= stacksize; + stacksize *= 2; +#endif +#if FLOATING_STACKS + /* Can unmap safely. */ + munmap(guardaddr, stacksize + guardsize); #else - char *guardaddr = th->p_guardaddr; - /* We unmap exactly what we mapped, in case there was something - else in the same region. Guardaddr is always set, eve if - guardsize is 0. This allows us to compute everything else. */ - size_t stacksize = (char *)(th+1) - guardaddr - guardsize; - - munmap (guardaddr, stacksize + guardsize); + /* Only remap to PROT_NONE, so that the region is reserved in + case we map the stack again later. Avoid collision with + other mmap()s, in particular by malloc(). */ + mmap(guardaddr, stacksize + guardsize, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); #endif } } diff --git a/malloc/malloc.c b/malloc/malloc.c index 187c814..1ac3b5d 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -423,11 +423,12 @@ Void_t* memmove(); #endif #endif -#if USE_MEMCPY - /* The following macros are only invoked with (2n+1)-multiples of INTERNAL_SIZE_T units, with a positive integer n. This is exploited - for fast inline execution when n is small. */ + for fast inline execution when n is small. If the regions to be + copied do overlap, the destination lies always _below_ the source. */ + +#if USE_MEMCPY #define MALLOC_ZERO(charp, nbytes) \ do { \ @@ -446,7 +447,9 @@ do { \ } else memset((charp), 0, mzsz); \ } while(0) -#define MALLOC_COPY(dest,src,nbytes) \ +/* If the regions overlap, dest is always _below_ src. */ + +#define MALLOC_COPY(dest,src,nbytes,overlap) \ do { \ INTERNAL_SIZE_T mcsz = (nbytes); \ if(mcsz <= 9*sizeof(mcsz)) { \ @@ -461,12 +464,12 @@ do { \ *mcdst++ = *mcsrc++; \ *mcdst++ = *mcsrc++; \ *mcdst = *mcsrc ; \ - } else memcpy(dest, src, mcsz); \ + } else if(overlap) \ + memmove(dest, src, mcsz); \ + else \ + memcpy(dest, src, mcsz); \ } while(0) -#define MALLOC_MEMMOVE(dest,src,nbytes) \ - memmove(dest, src, mcsz) - #else /* !USE_MEMCPY */ /* Use Duff's device for good zeroing/copying performance. */ @@ -488,7 +491,9 @@ do { \ } \ } while(0) -#define MALLOC_COPY(dest,src,nbytes) \ +/* If the regions overlap, dest is always _below_ src. */ + +#define MALLOC_COPY(dest,src,nbytes,overlap) \ do { \ INTERNAL_SIZE_T* mcsrc = (INTERNAL_SIZE_T*) src; \ INTERNAL_SIZE_T* mcdst = (INTERNAL_SIZE_T*) dest; \ @@ -3255,7 +3260,7 @@ Void_t* rEALLOc(oldmem, bytes) Void_t* oldmem; size_t bytes; /* Must alloc, copy, free. */ newmem = mALLOc(bytes); if (newmem == 0) return 0; /* propagate failure */ - MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ); + MALLOC_COPY(newmem, oldmem, oldsize - 2*SIZE_SZ, 0); munmap_chunk(oldp); return newmem; } @@ -3370,7 +3375,8 @@ arena* ar_ptr; mchunkptr oldp; INTERNAL_SIZE_T oldsize, nb; unlink(prev, bck, fwd); newp = prev; newsize += prevsize + nextsize; - MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize); + MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize, + 1); top(ar_ptr) = chunk_at_offset(newp, nb); set_head(top(ar_ptr), (newsize - nb) | PREV_INUSE); set_head_size(newp, nb); @@ -3385,7 +3391,7 @@ arena* ar_ptr; mchunkptr oldp; INTERNAL_SIZE_T oldsize, nb; unlink(prev, bck, fwd); newp = prev; newsize += nextsize + prevsize; - MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize); + MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize, 1); goto split; } } @@ -3396,7 +3402,7 @@ arena* ar_ptr; mchunkptr oldp; INTERNAL_SIZE_T oldsize, nb; unlink(prev, bck, fwd); newp = prev; newsize += prevsize; - MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize); + MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize, 1); goto split; } } @@ -3436,7 +3442,7 @@ arena* ar_ptr; mchunkptr oldp; INTERNAL_SIZE_T oldsize, nb; } /* Otherwise copy, free, and exit */ - MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize); + MALLOC_COPY(BOUNDED_N(chunk2mem(newp), oldsize), oldmem, oldsize, 0); chunk_free(ar_ptr, oldp); return newp; } @@ -4605,7 +4611,7 @@ realloc_check(oldmem, bytes, caller) newp = (top_check() >= 0) ? chunk_alloc(&main_arena, nb) : NULL; if (newp) { MALLOC_COPY(BOUNDED_N(chunk2mem(newp), nb), - oldmem, oldsize - 2*SIZE_SZ); + oldmem, oldsize - 2*SIZE_SZ, 0); munmap_chunk(oldp); } } -- 2.7.4