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 --- rust/syn/README.md | 13 +++++++++++++ 1 file changed, 13 insertions(+) create mode 100644 rust/syn/README.md (limited to 'rust/syn/README.md') diff --git a/rust/syn/README.md b/rust/syn/README.md new file mode 100644 index 000000000..d3e3981da --- /dev/null +++ b/rust/syn/README.md @@ -0,0 +1,13 @@ +# `syn` + +These source files come from the Rust `syn` crate, version 2.0.106 +(released 2025-08-16), hosted in the +repository, licensed under "Apache-2.0 OR MIT" and only modified to add +the SPDX license identifiers and to remove the `unicode-ident` +dependency. + +For copyright details, please see: + + https://github.com/dtolnay/syn/blob/2.0.106/README.md#license + https://github.com/dtolnay/syn/blob/2.0.106/LICENSE-APACHE + https://github.com/dtolnay/syn/blob/2.0.106/LICENSE-MIT -- cgit v1.3.1