Messages in this thread Patch in this message | | | From | Thomas Gleixner <> | Subject | [PATCH] x86/fpu: Reset state for all signal restore failures | Date | Wed, 09 Jun 2021 21:18:00 +0200 |
| |
If access_ok() or fpregs_soft_set() fails in __fpu__restore_sig() then the function just returns but does not clear the FPU state as it does for all other fatal failures.
Clear the FPU state for these failures as well.
Fixes: 72a671ced66d ("x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org --- arch/x86/kernel/fpu/signal.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-)
--- a/arch/x86/kernel/fpu/signal.c +++ b/arch/x86/kernel/fpu/signal.c @@ -307,13 +307,17 @@ static int __fpu__restore_sig(void __use return 0; } - if (!access_ok(buf, size)) - return -EACCES; + if (!access_ok(buf, size)) { + ret = -EACCES; + goto out; + } - if (!static_cpu_has(X86_FEATURE_FPU)) - return fpregs_soft_set(current, NULL, - 0, sizeof(struct user_i387_ia32_struct), - NULL, buf) != 0; + if (!static_cpu_has(X86_FEATURE_FPU)) { + ret = fpregs_soft_set(current, NULL, 0, + sizeof(struct user_i387_ia32_struct), + NULL, buf); + goto out; + } if (use_xsave()) { struct _fpx_sw_bytes fx_sw_user; @@ -377,7 +381,7 @@ static int __fpu__restore_sig(void __use */ ret = __copy_from_user(&env, buf, sizeof(env)); if (ret) - goto err_out; + goto out; envp = &env; } @@ -434,7 +438,7 @@ static int __fpu__restore_sig(void __use ret = __copy_from_user(&fpu->state.fxsave, buf_fx, state_size); if (ret) { ret = -EFAULT; - goto err_out; + goto out; } sanitize_restored_user_xstate(&fpu->state, envp, user_xfeatures, @@ -452,7 +456,7 @@ static int __fpu__restore_sig(void __use } else { ret = __copy_from_user(&fpu->state.fsave, buf_fx, state_size); if (ret) - goto err_out; + goto out; fpregs_lock(); ret = copy_kernel_to_fregs_err(&fpu->state.fsave); @@ -463,7 +467,7 @@ static int __fpu__restore_sig(void __use fpregs_deactivate(fpu); fpregs_unlock(); -err_out: +out: if (ret) fpu__clear_user_states(fpu); return ret;
| |