diff options
| -rw-r--r-- | lib/libc/stdlib/malloc.c | 76 |
1 files changed, 40 insertions, 36 deletions
diff --git a/lib/libc/stdlib/malloc.c b/lib/libc/stdlib/malloc.c index 1b470be..9b0fccc 100644 --- a/lib/libc/stdlib/malloc.c +++ b/lib/libc/stdlib/malloc.c @@ -1029,8 +1029,8 @@ base_chunk_alloc(size_t minsize) malloc_mutex_unlock(&brk_mtx); base_chunk = brk_cur; base_next_addr = base_chunk; - base_past_addr = (void *)((uintptr_t)base_chunk + - incr); + base_past_addr = (void *)((uintptr_t)base_chunk + + incr); #ifdef MALLOC_STATS base_total += incr; #endif @@ -1042,8 +1042,8 @@ base_chunk_alloc(size_t minsize) #endif /* - * Don't worry about chunk alignment here, since base_chunk doesn't really - * need to be aligned. + * Don't worry about chunk alignment here, since base_chunk doesn't + * really need to be aligned. */ base_chunk = pages_map(NULL, chunk_size); if (base_chunk == NULL) @@ -1067,8 +1067,12 @@ base_alloc(size_t size) malloc_mutex_lock(&base_mtx); - /* Make sure there's enough space for the allocation. */ - if ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) { + /* + * Make sure there's enough space for the allocation. + * base_chunk_alloc() does not guarantee that a newly allocated chunk + * is >= size, so loop here, rather than only trying once. + */ + while ((uintptr_t)base_next_addr + csize > (uintptr_t)base_past_addr) { if (base_chunk_alloc(csize)) { ret = NULL; goto RETURN; @@ -1299,6 +1303,36 @@ chunk_alloc(size_t size) } } + /* + * Try to over-allocate, but allow the OS to place the allocation + * anywhere. Beware of size_t wrap-around. + */ + if (size + chunk_size > size) { + if ((ret = pages_map(NULL, size + chunk_size)) != NULL) { + size_t offset = CHUNK_ADDR2OFFSET(ret); + + /* + * Success. Clean up unneeded leading/trailing space. + */ + if (offset != 0) { + /* Leading space. */ + pages_unmap(ret, chunk_size - offset); + + ret = (void *)((uintptr_t)ret + (chunk_size - + offset)); + + /* Trailing space. */ + pages_unmap((void *)((uintptr_t)ret + size), + offset); + } else { + /* Trailing space only. */ + pages_unmap((void *)((uintptr_t)ret + size), + chunk_size); + } + goto RETURN; + } + } + #ifdef USE_BRK /* * Try to create allocations in brk, in order to make full use of @@ -1342,36 +1376,6 @@ chunk_alloc(size_t size) } #endif - /* - * Try to over-allocate, but allow the OS to place the allocation - * anywhere. Beware of size_t wrap-around. - */ - if (size + chunk_size > size) { - if ((ret = pages_map(NULL, size + chunk_size)) != NULL) { - size_t offset = CHUNK_ADDR2OFFSET(ret); - - /* - * Success. Clean up unneeded leading/trailing space. - */ - if (offset != 0) { - /* Leading space. */ - pages_unmap(ret, chunk_size - offset); - - ret = (void *)((uintptr_t)ret + (chunk_size - - offset)); - - /* Trailing space. */ - pages_unmap((void *)((uintptr_t)ret + size), - offset); - } else { - /* Trailing space only. */ - pages_unmap((void *)((uintptr_t)ret + size), - chunk_size); - } - goto RETURN; - } - } - /* All strategies for allocation failed. */ ret = NULL; RETURN: |
