diff options
| author | Konstantin Belousov <kib@FreeBSD.org> | 2026-05-11 01:12:30 +0000 |
|---|---|---|
| committer | Konstantin Belousov <kib@FreeBSD.org> | 2026-05-13 19:40:03 +0000 |
| commit | cb31a266167c8bde3488fbdd6bf24c38b6f59977 (patch) | |
| tree | 1e63d8b7a8970160dec6232e8d79ea4d3cf0b8e0 | |
| parent | 54d0ae979d9596399f33dc7d7245866f86ab7f8e (diff) | |
ptrace: clear TDP_USERWR after transparent attach only on attach
The flag indicates that the modifying ptrace op was issued, and clearing
it after transparent attach is needed to not leak the flag to later
operations, since it is cleared on the syscall enter.
But clearing it there unconditionally is too strong. The clearing
should be only done for attach situation.
Reported by: Alex S <iwtcex@gmail.com>
Fixes: 99976934274de6fa19f049a0b6eac10856710f96
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D56928
| -rw-r--r-- | sys/kern/sys_process.c | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c index dece6457a4bf..5effc6fbe2d7 100644 --- a/sys/kern/sys_process.c +++ b/sys/kern/sys_process.c @@ -1411,17 +1411,16 @@ kern_ptrace(struct thread *td, int req, pid_t pid, void *addr, int data) * register file or specifying the pc, make the thread * xstopped by waking it up. */ - if ((td2->td_dbgflags & TDB_USERWR) != 0) { - if (pt_attach_transparent) { - thread_lock(td2); - if (TD_ON_SLEEPQ(td2) && - (td2->td_flags & TDF_SINTR) != 0) { - sleepq_abort(td2, EINTR); - } else { - thread_unlock(td2); - } + if ((td2->td_dbgflags & TDB_USERWR) != 0 && + pt_attach_transparent) { + thread_lock(td2); + if (TD_ON_SLEEPQ(td2) && + (td2->td_flags & TDF_SINTR) != 0) { + td2->td_dbgflags &= ~TDB_USERWR; + sleepq_abort(td2, EINTR); + } else { + thread_unlock(td2); } - td2->td_dbgflags &= ~TDB_USERWR; } /* |