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| author | Ivan Maidanski <ivmai@mail.ru> | 2022-12-11 23:18:18 +0300 |
|---|---|---|
| committer | Ivan Maidanski <ivmai@mail.ru> | 2022-12-11 23:18:18 +0300 |
| commit | 128c0ec33dc7b41c1ea40ca27d57821135744182 (patch) | |
| tree | 38d482b6fd10341d89c0659d2f3f55179b352840 /darwin_stop_world.c | |
| parent | 8fd5c0d9787c1bc01d45964014e866d3a3f8ddf5 (diff) | |
| download | bdwgc-128c0ec33dc7b41c1ea40ca27d57821135744182.tar.gz | |
Fix possible null pointer dereference in GC_stack_range_for
(fix of commit 7eb49a4e6)
Issue #362 (bdwgc).
* darwin_stop_world.c (GC_stack_range_for): Do not set crtn local
variable value until p is guaranteed to be non-NULL (i.e., do not set
crtn value unless DARWIN_DONT_PARSE_STACK).
Diffstat (limited to 'darwin_stop_world.c')
| -rw-r--r-- | darwin_stop_world.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/darwin_stop_world.c b/darwin_stop_world.c index 5debf480..53824970 100644 --- a/darwin_stop_world.c +++ b/darwin_stop_world.c @@ -142,7 +142,7 @@ STATIC ptr_t GC_stack_range_for(ptr_t *phi, thread_act_t thread, GC_thread p, mach_port_t my_thread, ptr_t *paltstack_lo, ptr_t *paltstack_hi, GC_bool *pfound_me) { - GC_stack_context_t crtn = p -> crtn; + GC_stack_context_t crtn; ptr_t lo; if (thread == my_thread) { @@ -153,9 +153,9 @@ STATIC ptr_t GC_stack_range_for(ptr_t *phi, thread_act_t thread, GC_thread p, # endif *pfound_me = TRUE; } else if (p != NULL && (p -> flags & DO_BLOCKING) != 0) { - lo = crtn -> stack_ptr; + lo = p -> crtn -> stack_ptr; # ifndef DARWIN_DONT_PARSE_STACK - *phi = crtn -> topOfStack; + *phi = p -> crtn -> topOfStack; # endif } else { @@ -327,6 +327,7 @@ STATIC ptr_t GC_stack_range_for(ptr_t *phi, thread_act_t thread, GC_thread p, UNUSED_ARG(paltstack_hi); # else /* p is guaranteed to be non-NULL regardless of GC_query_task_threads. */ + crtn = p -> crtn; *phi = EXPECT((p -> flags & MAIN_THREAD) == 0, TRUE) ? crtn -> stack_end : GC_stackbottom; if (crtn -> altstack != NULL && (word)(crtn -> altstack) <= (word)lo |