diff options
Diffstat (limited to 'sljit/sljitExecAllocator.c')
| -rw-r--r-- | sljit/sljitExecAllocator.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/sljit/sljitExecAllocator.c b/sljit/sljitExecAllocator.c index 3b37a97..92ddb94 100644 --- a/sljit/sljitExecAllocator.c +++ b/sljit/sljitExecAllocator.c @@ -118,10 +118,20 @@ static SLJIT_INLINE int get_map_jit_flag() if (map_jit_flag == -1) { struct utsname name; + map_jit_flag = 0; uname(&name); /* Kernel version for 10.14.0 (Mojave) */ - map_jit_flag = (atoi(name.release) >= 18) ? MAP_JIT : 0; + if (atoi(name.release) >= 18) { + /* Only use MAP_JIT if a hardened runtime is used, because MAP_JIT is incompatible with fork(). */ + void *ptr = mmap(NULL, getpagesize(), PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); + + if (ptr == MAP_FAILED) { + map_jit_flag = MAP_JIT; + } else { + munmap(ptr, getpagesize()); + } + } } return map_jit_flag; @@ -137,6 +147,7 @@ static SLJIT_INLINE int get_map_jit_flag() static SLJIT_INLINE void* alloc_chunk(sljit_uw size) { void *retval; + const int prot = PROT_READ | PROT_WRITE | PROT_EXEC; #ifdef MAP_ANON @@ -146,16 +157,25 @@ static SLJIT_INLINE void* alloc_chunk(sljit_uw size) flags |= get_map_jit_flag(); #endif - retval = mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC, flags, -1, 0); + retval = mmap(NULL, size, prot, flags, -1, 0); #else /* !MAP_ANON */ if (dev_zero < 0) { if (open_dev_zero()) return NULL; } - retval = mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, dev_zero, 0); + retval = mmap(NULL, size, prot, MAP_PRIVATE, dev_zero, 0); #endif /* MAP_ANON */ - return (retval != MAP_FAILED) ? retval : NULL; + if (retval == MAP_FAILED) + retval = NULL; + else { + if (mprotect(retval, size, prot) < 0) { + munmap(retval, size); + retval = NULL; + } + } + + return retval; } static SLJIT_INLINE void free_chunk(void *chunk, sljit_uw size) |