diff options
Diffstat (limited to 'lib/libc/stdlib/malloc.3')
| -rw-r--r-- | lib/libc/stdlib/malloc.3 | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/lib/libc/stdlib/malloc.3 b/lib/libc/stdlib/malloc.3 index 6a012fd23df..74df922f4bc 100644 --- a/lib/libc/stdlib/malloc.3 +++ b/lib/libc/stdlib/malloc.3 @@ -30,9 +30,9 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.\" $OpenBSD: malloc.3,v 1.70 2011/07/22 07:00:44 otto Exp $ +.\" $OpenBSD: malloc.3,v 1.71 2012/11/02 18:18:15 djm Exp $ .\" -.Dd $Mdocdate: July 22 2011 $ +.Dd $Mdocdate: November 2 2012 $ .Dt MALLOC 3 .Os .Sh NAME @@ -231,13 +231,17 @@ This option requires the library to have been compiled with -DMALLOC_STATS in order to have any effect. .It Cm F .Dq Freeguard . -Enable use after free protection. +Enable use after free detection. Unused pages on the freelist are read and write protected to cause a segmentation fault upon access. This will also switch off the delayed freeing of chunks, reducing random behaviour but detecting double .Fn free calls as early as possible. +This option is intended for debugging rather than improved security +(use the +.Cm U +option for security). .It Cm G .Dq Guard . Enable guard pages. @@ -275,6 +279,11 @@ This can substantially aid in compacting memory. .\"Consult the source for this one. .It Cm S Enable all options suitable for security auditing. +.It Cm U +.Dq Free unmap . +Enable use after free protection for larger allocations. +Unused pages on the freelist are read and write protected to +cause a segmentation fault upon access. .It Cm X .Dq xmalloc . Rather than return failure, |