s390 fixes for 5.8-rc2
- Few ptrace fixes mostly for strace and seccomp_bpf kernel tests
findings.
- Cleanup unused pm callbacks in virtio ccw.
- Replace kmalloc + memset with kzalloc in crypto.
- Use $(LD) for vDSO linkage to make clang happy.
- Fix vDSO clock_getres() to preserve the same behaviour as
posix_get_hrtimer_res().
- Fix workqueue cpumask warning when NUMA=n and nr_node_ids=2.
- Reduce SLSB writes during input processing, improve warnings and
cleanup qdio_data usage in qdio.
- Few fixes to use scnprintf() instead of snprintf().
s390: fix syscall_get_error for compat processes
If both the tracer and the tracee are compat processes, and gprs[2]
is assigned a value by __poke_user_compat, then the higher 32 bits
of gprs[2] are cleared, IS_ERR_VALUE() always returns false, and
syscall_get_error() always returns 0.
Fix the implementation by sign-extending the value for compat processes
the same way as x86 implementation does.
The bug was exposed to user space by commit 201766a20e30f ("ptrace: add
PTRACE_GET_SYSCALL_INFO request") and detected by strace test suite.
This change fixes strace syscall tampering on s390.
Link: https://lkml.kernel.org/r/20200602180051.GA2427@altlinux.org
Fixes: 753c4dd6a2fa2 ("[S390] ptrace changes")
Cc: Elvira Khabirova <lineprinter@altlinux.org>
Cc: stable@vger.kernel.org # v2.6.28+
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
1 file changed
