diff options
Diffstat (limited to 'usr/src/lib/libmtmalloc/common/mtmalloc.c')
| -rw-r--r-- | usr/src/lib/libmtmalloc/common/mtmalloc.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/usr/src/lib/libmtmalloc/common/mtmalloc.c b/usr/src/lib/libmtmalloc/common/mtmalloc.c index c71024abc8..ab502274c5 100644 --- a/usr/src/lib/libmtmalloc/common/mtmalloc.c +++ b/usr/src/lib/libmtmalloc/common/mtmalloc.c @@ -20,7 +20,7 @@ * CDDL HEADER END */ /* - * Copyright 2004 Sun Microsystems, Inc. All rights reserved. + * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -168,6 +168,10 @@ extern uint_t _thr_self(); #define MIN_CACHED_SHIFT 4 /* smaller requests rounded up */ #define MTMALLOC_MIN_ALIGN 8 /* min guaranteed alignment */ +/* maximum size before overflow */ +#define MAX_MTMALLOC (SIZE_MAX - (SIZE_MAX % MTMALLOC_MIN_ALIGN) \ + - OVSZ_HEADER_SIZE) + #define NUM_CACHES (MAX_CACHED_SHIFT - MIN_CACHED_SHIFT + 1) #define CACHELIST_SIZE ALIGN(NUM_CACHES * sizeof (cache_head_t), \ CACHE_COHERENCY_UNIT) @@ -1209,12 +1213,11 @@ oversize(size_t size) oversize_t *big; int bucket; - /* - * The idea with the global lock is that we are sure to - * block in the kernel anyway since given an oversize alloc - * we are sure to have to call morecore(); - */ - (void) mutex_lock(&oversize_lock); + /* make sure we will not overflow */ + if (size > MAX_MTMALLOC) { + errno = ENOMEM; + return (NULL); + } /* * Since we ensure every address we hand back is @@ -1225,6 +1228,13 @@ oversize(size_t size) */ size = ALIGN(size, MTMALLOC_MIN_ALIGN); + /* + * The idea with the global lock is that we are sure to + * block in the kernel anyway since given an oversize alloc + * we are sure to have to call morecore(); + */ + (void) mutex_lock(&oversize_lock); + if ((big = find_oversize(size)) != NULL) { if (reinit == 0 && (debugopt & MTDEBUGPATTERN)) if (verify_pattern(FREEPATTERN, big->addr, size)) |