Messages in this thread Patch in this message | | | From | Rolf Eike Beer <> | Subject | [PATCH] fs/exec.c: simplify initial stack size expansion | Date | Wed, 19 Oct 2022 09:32:35 +0200 |
| |
I had a hard time trying to understand completely why it is using vm_end in one side of the expression and vm_start in the other one, and using something in the "if" clause that is not an exact copy of what is used below. The whole point is that the stack_size variable that was used in the "if" clause is the difference between vm_start and vm_end, which is not far away but makes this thing harder to read than it must be.
Signed-off-by: Rolf Eike Beer <eb@emlix.com> --- fs/exec.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c index 768843477a49..990891c5d8fe 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -840,16 +840,13 @@ int setup_arg_pages(struct linux_binprm *bprm, * will align it up. */ rlim_stack = bprm->rlim_stack.rlim_cur & PAGE_MASK; + + stack_expand = min(rlim_stack, stack_size + stack_expand); + #ifdef CONFIG_STACK_GROWSUP - if (stack_size + stack_expand > rlim_stack) - stack_base = vma->vm_start + rlim_stack; - else - stack_base = vma->vm_end + stack_expand; + stack_base = vma->vm_start + stack_expand; #else - if (stack_size + stack_expand > rlim_stack) - stack_base = vma->vm_end - rlim_stack; - else - stack_base = vma->vm_start - stack_expand; + stack_base = vma->vm_end - stack_expand; #endif current->mm->start_stack = bprm->p; ret = expand_stack(vma, stack_base); -- 2.37.3
-- Rolf Eike Beer, emlix GmbH, https://www.emlix.com Fon +49 551 30664-0, Fax +49 551 30664-11 Gothaer Platz 3, 37083 Göttingen, Germany Sitz der Gesellschaft: Göttingen, Amtsgericht Göttingen HR B 3160 Geschäftsführung: Heike Jordan, Dr. Uwe Kracke – Ust-IdNr.: DE 205 198 055
emlix - smart embedded open source
| |