diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2021-06-23 14:01:50 +0200 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2021-06-23 17:52:41 +0200 |
| commit | 9fe8a6f5eed8fff6b2d7dbc99b911334e311732d (patch) | |
| tree | 6130bcbe9413b23bf5556f1af3c78bdb1db1d78f /arch/x86/kernel/fpu/xstate.c | |
| parent | 71ef453355a9197fcfd8ff22391a4ad7861d79e6 (diff) | |
x86/fpu: Cleanup arch_set_user_pkey_access()
The function does a sanity check with a WARN_ON_ONCE() but happily proceeds
when the pkey argument is out of range.
Clean it up.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121453.635764326@linutronix.de
Diffstat (limited to 'arch/x86/kernel/fpu/xstate.c')
| -rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 185cc5d1aa33..579e343e6654 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -912,11 +912,10 @@ EXPORT_SYMBOL_GPL(get_xsave_addr); * rights for @pkey to @init_val. */ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, - unsigned long init_val) + unsigned long init_val) { - u32 old_pkru; - int pkey_shift = (pkey * PKRU_BITS_PER_PKEY); - u32 new_pkru_bits = 0; + u32 old_pkru, new_pkru_bits = 0; + int pkey_shift; /* * This check implies XSAVE support. OSPKE only gets @@ -930,7 +929,8 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, * values originating from in-kernel users. Complain * if a bad value is observed. */ - WARN_ON_ONCE(pkey >= arch_max_pkey()); + if (WARN_ON_ONCE(pkey >= arch_max_pkey())) + return -EINVAL; /* Set the bits we need in PKRU: */ if (init_val & PKEY_DISABLE_ACCESS) @@ -939,6 +939,7 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, new_pkru_bits |= PKRU_WD_BIT; /* Shift the bits in to the correct place in PKRU for pkey: */ + pkey_shift = pkey * PKRU_BITS_PER_PKEY; new_pkru_bits <<= pkey_shift; /* Get old PKRU and mask off any old bits in place: */ |