From: Nam Cao Date: Sun, 4 May 2025 10:19:20 +0000 (+0200) Subject: riscv: Fix kernel crash due to PR_SET_TAGGED_ADDR_CTRL X-Git-Tag: v6.15-rc6~19^2^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ae08d55807c099357c047dba17624b09414635dd;p=thirdparty%2Fkernel%2Flinux.git riscv: Fix kernel crash due to PR_SET_TAGGED_ADDR_CTRL When userspace does PR_SET_TAGGED_ADDR_CTRL, but Supm extension is not available, the kernel crashes: Oops - illegal instruction [#1] [snip] epc : set_tagged_addr_ctrl+0x112/0x15a ra : set_tagged_addr_ctrl+0x74/0x15a epc : ffffffff80011ace ra : ffffffff80011a30 sp : ffffffc60039be10 [snip] status: 0000000200000120 badaddr: 0000000010a79073 cause: 0000000000000002 set_tagged_addr_ctrl+0x112/0x15a __riscv_sys_prctl+0x352/0x73c do_trap_ecall_u+0x17c/0x20c andle_exception+0x150/0x15c Fix it by checking if Supm is available. Fixes: 09d6775f503b ("riscv: Add support for userspace pointer masking") Signed-off-by: Nam Cao Cc: stable@vger.kernel.org Reviewed-by: Samuel Holland Link: https://lore.kernel.org/r/20250504101920.3393053-1-namcao@linutronix.de Signed-off-by: Alexandre Ghiti --- diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 7c244de771800..3db2c0c07acd0 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -275,6 +275,9 @@ long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg) unsigned long pmm; u8 pmlen; + if (!riscv_has_extension_unlikely(RISCV_ISA_EXT_SUPM)) + return -EINVAL; + if (is_compat_thread(ti)) return -EINVAL;