| commit | 81be2a61dafc168327c1639e97b6dae128c7ccf3 | |
| author | H.J. Lu <hjl.tools@gmail.com> | |
| Thu, 21 Dec 2023 03:42:12 +0000 (20 19:42 -0800) | ||
| committer | H.J. Lu <hjl.tools@gmail.com> | |
| Fri, 22 Dec 2023 13:37:17 +0000 (22 05:37 -0800) | ||
| tree | 0f56678699b9deab602178f811dd9f0c45a22472 | treesnapshot (tar.gz zip) |
| parent | 3502440397bbb840e2f7223734aa5cc2cc0e29b6 | commitdiff |
x86-64: Fix the tcb field load for x32 [BZ #31185]
_dl_tlsdesc_undefweak and _dl_tlsdesc_dynamic access the thread pointer
via the tcb field in TCB:
_dl_tlsdesc_undefweak:
_CET_ENDBR
movq 8(%rax), %rax
subq %fs:0, %rax
ret
_dl_tlsdesc_dynamic:
...
subq %fs:0, %rax
movq -8(%rsp), %rdi
ret
Since the tcb field in TCB is a pointer, %fs:0 is a 32-bit location,
not 64-bit. It should use "sub %fs:0, %RAX_LP" instead. Since
_dl_tlsdesc_undefweak returns ptrdiff_t and _dl_make_tlsdesc_dynamic
returns void *, RAX_LP is appropriate here for x32 and x86-64. This
fixes BZ #31185.
_dl_tlsdesc_undefweak and _dl_tlsdesc_dynamic access the thread pointer
via the tcb field in TCB:
_dl_tlsdesc_undefweak:
_CET_ENDBR
movq 8(%rax), %rax
subq %fs:0, %rax
ret
_dl_tlsdesc_dynamic:
...
subq %fs:0, %rax
movq -8(%rsp), %rdi
ret
Since the tcb field in TCB is a pointer, %fs:0 is a 32-bit location,
not 64-bit. It should use "sub %fs:0, %RAX_LP" instead. Since
_dl_tlsdesc_undefweak returns ptrdiff_t and _dl_make_tlsdesc_dynamic
returns void *, RAX_LP is appropriate here for x32 and x86-64. This
fixes BZ #31185.
| sysdeps/x86_64/dl-tlsdesc.S | diffblobblamehistory |