mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-09-26 18:29:57 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

bpo-21131: Fix faulthandler.register(chain=True) stack (GH-15276)

Browse source 
faulthandler now allocates a dedicated stack of SIGSTKSZ*2 bytes,
instead of just SIGSTKSZ bytes. Calling the previous signal handler
in faulthandler signal handler uses more than SIGSTKSZ bytes of stack
memory on some platforms.
(cherry picked from commit ac827edc49)

Co-authored-by: Victor Stinner <vstinner@redhat.com>
This commit is contained in:
Miss Islington (bot) 2019-08-14 15:02:12 -07:00 • committed by GitHub
parent 123f6c4914
commit b8e682427a
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 9 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

4
Misc/NEWS.d/next/Library/2019-08-14-15-34-23.bpo-21131.0MMQRi.rst Normal file
View file

@ -0,0 +1,4 @@
Fix ``faulthandler.register(chain=True)`` stack. faulthandler now allocates a
dedicated stack of ``SIGSTKSZ*2`` bytes, instead of just ``SIGSTKSZ`` bytes.
Calling the previous signal handler in faulthandler signal handler uses more
than ``SIGSTKSZ`` bytes of stack memory on some platforms.

6
Modules/faulthandler.c
View file

@ -1325,7 +1325,11 @@ _PyFaulthandler_Init(int enable)
* be able to allocate memory on the stack, even on a stack overflow. If it * be able to allocate memory on the stack, even on a stack overflow. If it
* fails, ignore the error. */ * fails, ignore the error. */
stack.ss_flags = 0; stack.ss_flags = 0;
stack.ss_size = SIGSTKSZ; /* bpo-21131: allocate dedicated stack of SIGSTKSZ*2 bytes, instead of just
SIGSTKSZ bytes. Calling the previous signal handler in faulthandler
signal handler uses more than SIGSTKSZ bytes of stack memory on some
platforms. */
stack.ss_size = SIGSTKSZ * 2;
stack.ss_sp = PyMem_Malloc(stack.ss_size); stack.ss_sp = PyMem_Malloc(stack.ss_size);
if (stack.ss_sp != NULL) { if (stack.ss_sp != NULL) {
err = sigaltstack(&stack, &old_stack); err = sigaltstack(&stack, &old_stack);