From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- scripts/jobserver-exec | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100755 scripts/jobserver-exec (limited to 'scripts/jobserver-exec') diff --git a/scripts/jobserver-exec b/scripts/jobserver-exec new file mode 100755 index 000000000..21b319e6c --- /dev/null +++ b/scripts/jobserver-exec @@ -0,0 +1,35 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0+ + +""" +Determines how many parallel tasks "make" is expecting, as it is +not exposed via any special variables, reserves them all, runs a subprocess +with PARALLELISM environment variable set, and releases the jobs back again. + +See: + https://www.gnu.org/software/make/manual/html_node/POSIX-Jobserver.html#POSIX-Jobserver +""" + +import os +import sys + +LIB_DIR = "../tools/lib/python" +SRC_DIR = os.path.dirname(os.path.realpath(__file__)) + +sys.path.insert(0, os.path.join(SRC_DIR, LIB_DIR)) + +from jobserver import JobserverExec # pylint: disable=C0415 + + +def main(): + """Main program""" + if len(sys.argv) < 2: + name = os.path.basename(__file__) + sys.exit("usage: " + name +" command [args ...]\n" + __doc__) + + with JobserverExec() as jobserver: + return jobserver.run(sys.argv[1:]) + + +if __name__ == "__main__": + sys.exit(main()) -- cgit v1.3.1