summaryrefslogtreecommitdiff
path: root/include/linux
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2021-07-07 11:12:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-07-07 11:12:01 -0700
commit1423e2660cf134a8f21f2451865a04792013e49e (patch)
tree8dd93d1e767af1907929b650e1e0d1243865eafc /include/linux
parent4ea90317956718e0648e1f87e56530db809a5a04 (diff)
parent93c2cdc975aab53c222472c5b96c2d41dbeb350c (diff)
Merge tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu updates from Thomas Gleixner: "Fixes and improvements for FPU handling on x86: - Prevent sigaltstack out of bounds writes. The kernel unconditionally writes the FPU state to the alternate stack without checking whether the stack is large enough to accomodate it. Check the alternate stack size before doing so and in case it's too small force a SIGSEGV instead of silently corrupting user space data. - MINSIGSTKZ and SIGSTKSZ are constants in signal.h and have never been updated despite the fact that the FPU state which is stored on the signal stack has grown over time which causes trouble in the field when AVX512 is available on a CPU. The kernel does not expose the minimum requirements for the alternate stack size depending on the available and enabled CPU features. ARM already added an aux vector AT_MINSIGSTKSZ for the same reason. Add it to x86 as well. - A major cleanup of the x86 FPU code. The recent discoveries of XSTATE related issues unearthed quite some inconsistencies, duplicated code and other issues. The fine granular overhaul addresses this, makes the code more robust and maintainable, which allows to integrate upcoming XSTATE related features in sane ways" * tag 'x86-fpu-2021-07-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits) x86/fpu/xstate: Clear xstate header in copy_xstate_to_uabi_buf() again x86/fpu/signal: Let xrstor handle the features to init x86/fpu/signal: Handle #PF in the direct restore path x86/fpu: Return proper error codes from user access functions x86/fpu/signal: Split out the direct restore code x86/fpu/signal: Sanitize copy_user_to_fpregs_zeroing() x86/fpu/signal: Sanitize the xstate check on sigframe x86/fpu/signal: Remove the legacy alignment check x86/fpu/signal: Move initial checks into fpu__restore_sig() x86/fpu: Mark init_fpstate __ro_after_init x86/pkru: Remove xstate fiddling from write_pkru() x86/fpu: Don't store PKRU in xstate in fpu_reset_fpstate() x86/fpu: Remove PKRU handling from switch_fpu_finish() x86/fpu: Mask PKRU from kernel XRSTOR[S] operations x86/fpu: Hook up PKRU into ptrace() x86/fpu: Add PKRU storage outside of task XSAVE buffer x86/fpu: Dont restore PKRU in fpregs_restore_userspace() x86/fpu: Rename xfeatures_mask_user() to xfeatures_mask_uabi() x86/fpu: Move FXSAVE_LEAK quirk info __copy_kernel_to_fpregs() x86/fpu: Rename __fpregs_load_activate() to fpregs_restore_userregs() ...
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/pkeys.h4
-rw-r--r--include/linux/sched/signal.h19
2 files changed, 12 insertions, 11 deletions
diff --git a/include/linux/pkeys.h b/include/linux/pkeys.h
index 2955ba976048..6beb26b7151d 100644
--- a/include/linux/pkeys.h
+++ b/include/linux/pkeys.h
@@ -44,10 +44,6 @@ static inline bool arch_pkeys_enabled(void)
return false;
}
-static inline void copy_init_pkru_to_fpregs(void)
-{
-}
-
#endif /* ! CONFIG_ARCH_HAS_PKEYS */
#endif /* _LINUX_PKEYS_H */
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
index c9cf678c347d..b9126fe06c3f 100644
--- a/include/linux/sched/signal.h
+++ b/include/linux/sched/signal.h
@@ -538,6 +538,17 @@ static inline int kill_cad_pid(int sig, int priv)
#define SEND_SIG_NOINFO ((struct kernel_siginfo *) 0)
#define SEND_SIG_PRIV ((struct kernel_siginfo *) 1)
+static inline int __on_sig_stack(unsigned long sp)
+{
+#ifdef CONFIG_STACK_GROWSUP
+ return sp >= current->sas_ss_sp &&
+ sp - current->sas_ss_sp < current->sas_ss_size;
+#else
+ return sp > current->sas_ss_sp &&
+ sp - current->sas_ss_sp <= current->sas_ss_size;
+#endif
+}
+
/*
* True if we are on the alternate signal stack.
*/
@@ -555,13 +566,7 @@ static inline int on_sig_stack(unsigned long sp)
if (current->sas_ss_flags & SS_AUTODISARM)
return 0;
-#ifdef CONFIG_STACK_GROWSUP
- return sp >= current->sas_ss_sp &&
- sp - current->sas_ss_sp < current->sas_ss_size;
-#else
- return sp > current->sas_ss_sp &&
- sp - current->sas_ss_sp <= current->sas_ss_size;
-#endif
+ return __on_sig_stack(sp);
}
static inline int sas_ss_flags(unsigned long sp)