hurd: Fix longjmp early in initialization

When e.g. an LD_PRELOAD fails, _dl_signal_exception/error longjmps, but TLS
is not initialized yet, let along signal state.  We thus mustn't look at
them within __longjmp.

* sysdeps/mach/hurd/i386/____longjmp_chk.S,__longjmp.S: Check for
initialized value of %gs, and that sigstate is non-NULL.
This commit is contained in:
Samuel Thibault 2020-07-18 15:08:03 +02:00
parent e9422236a2
commit 115bcf921a
2 changed files with 16 additions and 2 deletions

View File

@ -60,7 +60,14 @@ ENTRY (____longjmp_chk)
PTR_DEMANGLE (%ecx)
#endif
movl %gs:SIGSTATE_OFFSET,%edi
movw %ds, %si
movw %gs, %di
cmpw %si, %di
jz .Lok /* TLS not initialized yet */
movl %gs:SIGSTATE_OFFSET, %edi
testl %edi, %edi
jnz .Lok /* sigstate not initialized yet */
testl $SS_ONSTACK, (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_FLAGS__OFFSET)(%edi)
jnz .Lonstack

View File

@ -38,7 +38,14 @@ ENTRY (__longjmp)
PTR_DEMANGLE (%ecx)
#endif
movl %gs:SIGSTATE_OFFSET,%edi
movw %ds, %si
movw %gs, %di
cmpw %si, %di
jz .Lok /* TLS not initialized yet */
movl %gs:SIGSTATE_OFFSET, %edi
testl %edi, %edi
jnz .Lok /* sigstate not initialized yet */
testl $SS_ONSTACK, (HURD_SIGSTATE__SIGALTSTACK__OFFSET + SIGALTSTACK__SS_FLAGS__OFFSET)(%edi)
jz .Lok