Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2024-11-23 05:40:09 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

[dfsan] Don't clear shadow on dlopen(NULL, flags)

Browse Source 
This ports msan https://reviews.llvm.org/D14795 to dfsan.
dfsan, like msan, clears shadow for globals in a newly opened DSO in
case the DSO occupies the address of a previously labeled/poisoned area.
The operation should not happen on the main executable.

In addition, for a DT_EXEC executable, l_addr is zero and will lead to a
null pointer dereference in ForEachMappedRegion.
This commit is contained in:
Fangrui Song 2024-01-18 15:04:48 -08:00
parent 184c22dd3a
commit 8434e5d0a1
2 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
compiler-rt/lib/dfsan/dfsan_custom.cpp
View File

@ -842,7 +842,7 @@ __dfsw_dlopen(const char *filename, int flag, dfsan_label filename_label,
dfsan_label flag_label, dfsan_label *ret_label) {
void *handle = dlopen(filename, flag);
link_map *map = GET_LINK_MAP_BY_DLOPEN_HANDLE(handle);
if (map)
if (filename && map)
ForEachMappedRegion(map, dfsan_set_zero_label);
*ret_label = 0;
return handle;

2
compiler-rt/test/dfsan/custom.cpp
View File

@ -1,7 +1,7 @@
// RUN: %clang_dfsan %s -o %t && DFSAN_OPTIONS="strict_data_dependencies=0" %run %t
// RUN: %clang_dfsan -DSTRICT_DATA_DEPENDENCIES %s -o %t && %run %t
// RUN: %clang_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 -mllvm -dfsan-combine-pointer-labels-on-load=false -DSTRICT_DATA_DEPENDENCIES %s -o %t && %run %t
// RUN: %clang_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 -mllvm -dfsan-combine-pointer-labels-on-load=false %s -o %t && DFSAN_OPTIONS="strict_data_dependencies=0" %run %t
// RUN: %clang_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 -mllvm -dfsan-combine-pointer-labels-on-load=false -no-pie %s -o %t && DFSAN_OPTIONS="strict_data_dependencies=0" %run %t
//
// Tests custom implementations of various glibc functions.