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basic/raw-clone: refuse CLONE_PIDFD too

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This commit is contained in:
Mike Yuan
2024-09-01 10:44:39 +09:00
committed by Yu Watanabe
parent 229607bca8
commit 9517c81747
1 changed files with 6 additions and 6 deletions
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src/basic/raw-clone.h
+6 -6
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@@ -21,11 +21,12 @@
* parameter. Opposed to glibc's clone function, using this function does not set up a separate stack for the child, but
* relies on copy-on-write semantics on the one stack at a common virtual address, just as fork does.
*
* To obtain copy-on-write semantics, flags must not contain CLONE_VM, and thus CLONE_THREAD and CLONE_SIGHAND (which
* require CLONE_VM) are not usable.
* To obtain copy-on-write semantics, flags must not contain CLONE_VM, and thus CLONE_THREAD and CLONE_SIGHAND
* (which require CLONE_VM) are not usable.
*
* Additionally, as this function does not pass the ptid, newtls and ctid parameters to the kernel, flags must not
* contain CLONE_PARENT_SETTID, CLONE_CHILD_SETTID, CLONE_CHILD_CLEARTID or CLONE_SETTLS.
* Additionally, as this function does not pass the ptid (pidfd in the case of CLONE_PIDFD), newtls and ctid
* parameters to the kernel, flags must not contain CLONE_PARENT_SETTID, CLONE_CHILD_SETTID, CLONE_CHILD_CLEARTID,
* CLONE_SETTLS, or CLONE_PIDFD.
*
* WARNING: 💣 this call (just like glibc's own clone() wrapper) will not synchronize on glibc's malloc
* locks, which means they will be in an undefined state in the child if the parent is
@@ -37,8 +38,7 @@
static inline pid_t raw_clone(unsigned long flags) {
pid_t ret;
assert((flags & (CLONE_VM|CLONE_PARENT_SETTID|CLONE_CHILD_SETTID|
CLONE_CHILD_CLEARTID|CLONE_SETTLS)) == 0);
assert((flags & (CLONE_VM|CLONE_PARENT_SETTID|CLONE_CHILD_SETTID|CLONE_CHILD_CLEARTID|CLONE_SETTLS|CLONE_PIDFD)) == 0);
#if defined(__s390x__) || defined(__s390__) || defined(__CRIS__)
/* On s390/s390x and cris the order of the first and second arguments
* of the raw clone() system call is reversed. */