* Re: [PATCH 02/11] fs: don't allow kernel reads and writes without iter ops
From: Kees Cook @ 2020-08-18 19:34 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev
In-Reply-To: <20200817073212.830069-3-hch@lst.de>
On Mon, Aug 17, 2020 at 09:32:03AM +0200, Christoph Hellwig wrote:
> Don't allow calling ->read or ->write with set_fs as a preparation for
> killing off set_fs. All the instances that we use kernel_read/write on
> are using the iter ops already.
>
> If a file has both the regular ->read/->write methods and the iter
> variants those could have different semantics for messed up enough
> drivers. Also fails the kernel access to them in that case.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
^ permalink raw reply
* Re: [PATCH 01/11] mem: remove duplicate ops for /dev/zero and /dev/null
From: Kees Cook @ 2020-08-18 19:33 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev
In-Reply-To: <20200817073212.830069-2-hch@lst.de>
On Mon, Aug 17, 2020 at 09:32:02AM +0200, Christoph Hellwig wrote:
> There is no good reason to implement both the traditional ->read and
> ->write as well as the iter based ops. So implement just the iter
> based ones.
>
> Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
^ permalink raw reply
* Re: [PATCH 06/11] lkdtm: disable set_fs-based tests for !CONFIG_SET_FS
From: Kees Cook @ 2020-08-18 19:32 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev
In-Reply-To: <20200817073212.830069-7-hch@lst.de>
On Mon, Aug 17, 2020 at 09:32:07AM +0200, Christoph Hellwig wrote:
> Once we can't manipulate the address limit, we also can't test what
> happens when the manipulation is abused.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
> drivers/misc/lkdtm/bugs.c | 2 ++
> drivers/misc/lkdtm/core.c | 4 ++++
> drivers/misc/lkdtm/usercopy.c | 2 ++
> 3 files changed, 8 insertions(+)
>
> diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c
> index 4dfbfd51bdf774..66f1800b1cb82d 100644
> --- a/drivers/misc/lkdtm/bugs.c
> +++ b/drivers/misc/lkdtm/bugs.c
> @@ -312,6 +312,7 @@ void lkdtm_CORRUPT_LIST_DEL(void)
> pr_err("list_del() corruption not detected!\n");
> }
>
> +#ifdef CONFIG_SET_FS
> /* Test if unbalanced set_fs(KERNEL_DS)/set_fs(USER_DS) check exists. */
> void lkdtm_CORRUPT_USER_DS(void)
> {
> @@ -321,6 +322,7 @@ void lkdtm_CORRUPT_USER_DS(void)
> /* Make sure we do not keep running with a KERNEL_DS! */
> force_sig(SIGKILL);
> }
> +#endif
Please let the test defined, but it should XFAIL with a message about
the CONFIG (see similar ifdefs in lkdtm).
> /* Test that VMAP_STACK is actually allocating with a leading guard page */
> void lkdtm_STACK_GUARD_PAGE_LEADING(void)
> diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c
> index a5e344df916632..aae08b33a7ee2a 100644
> --- a/drivers/misc/lkdtm/core.c
> +++ b/drivers/misc/lkdtm/core.c
> @@ -112,7 +112,9 @@ static const struct crashtype crashtypes[] = {
> CRASHTYPE(CORRUPT_STACK_STRONG),
> CRASHTYPE(CORRUPT_LIST_ADD),
> CRASHTYPE(CORRUPT_LIST_DEL),
> +#ifdef CONFIG_SET_FS
> CRASHTYPE(CORRUPT_USER_DS),
> +#endif
> CRASHTYPE(STACK_GUARD_PAGE_LEADING),
> CRASHTYPE(STACK_GUARD_PAGE_TRAILING),
> CRASHTYPE(UNSET_SMEP),
> @@ -172,7 +174,9 @@ static const struct crashtype crashtypes[] = {
> CRASHTYPE(USERCOPY_STACK_FRAME_FROM),
> CRASHTYPE(USERCOPY_STACK_BEYOND),
> CRASHTYPE(USERCOPY_KERNEL),
> +#ifdef CONFIG_SET_FS
> CRASHTYPE(USERCOPY_KERNEL_DS),
> +#endif
> CRASHTYPE(STACKLEAK_ERASING),
> CRASHTYPE(CFI_FORWARD_PROTO),
Then none of these are needed.
> #ifdef CONFIG_X86_32
Hmpf, this ifdef was missed in ae56942c1474 ("lkdtm: Make arch-specific
tests always available"). I will fix that.
> diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c
> index b833367a45d053..4b632fe79ab6bb 100644
> --- a/drivers/misc/lkdtm/usercopy.c
> +++ b/drivers/misc/lkdtm/usercopy.c
> @@ -325,6 +325,7 @@ void lkdtm_USERCOPY_KERNEL(void)
> vm_munmap(user_addr, PAGE_SIZE);
> }
>
> +#ifdef CONFIG_SET_FS
> void lkdtm_USERCOPY_KERNEL_DS(void)
> {
> char __user *user_ptr =
> @@ -339,6 +340,7 @@ void lkdtm_USERCOPY_KERNEL_DS(void)
> pr_err("copy_to_user() to noncanonical address succeeded!?\n");
> set_fs(old_fs);
> }
> +#endif
(Same here, please.)
>
> void __init lkdtm_usercopy_init(void)
> {
> --
> 2.28.0
>
--
Kees Cook
^ permalink raw reply
* Re: [PATCH 07/11] x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h
From: Kees Cook @ 2020-08-18 19:27 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev
In-Reply-To: <20200817073212.830069-8-hch@lst.de>
On Mon, Aug 17, 2020 at 09:32:08AM +0200, Christoph Hellwig wrote:
> At least for 64-bit this moves them closer to some of the defines
> they are based on, and it prepares for using the TASK_SIZE_MAX
> definition from assembly.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
--
Kees Cook
^ permalink raw reply
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc
From: Christophe Leroy @ 2020-08-18 18:23 UTC (permalink / raw)
To: Christoph Hellwig
Cc: linux-arch, Kees Cook, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev
In-Reply-To: <20200818180555.GA29185@lst.de>
Le 18/08/2020 à 20:05, Christoph Hellwig a écrit :
> On Tue, Aug 18, 2020 at 07:46:22PM +0200, Christophe Leroy wrote:
>> I gave it a go on my powerpc mpc832x. I tested it on top of my newest
>> series that reworks the 32 bits signal handlers (see
>> https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=196278) with
>> the microbenchmark test used is that series.
>>
>> With KUAP activated, on top of signal32 rework, performance is boosted as
>> system time for the microbenchmark goes from 1.73s down to 1.56s, that is
>> 10% quicker
>>
>> Surprisingly, with the kernel as is today without my signal's series, your
>> series degrades performance slightly (from 2.55s to 2.64s ie 3.5% slower).
>>
>>
>> I also observe, in both cases, a degradation on
>>
>> dd if=/dev/zero of=/dev/null count=1M
>>
>> Without your series, it runs in 5.29 seconds.
>> With your series, it runs in 5.82 seconds, that is 10% more time.
>
> That's pretty strage, I wonder if some kernel text cache line
> effects come into play here?
>
> The kernel access side is only used in slow path code, so it should
> not make a difference, and the uaccess code is simplified and should be
> (marginally) faster.
>
> Btw, was this with the __{get,put}_user_allowed cockup that you noticed
> fixed?
>
Yes it is with the __get_user_size() replaced by __get_user_size_allowed().
Christophe
^ permalink raw reply
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc
From: Christoph Hellwig @ 2020-08-18 18:05 UTC (permalink / raw)
To: Christophe Leroy
Cc: linux-arch, Kees Cook, x86, linux-kernel, Al Viro, linux-fsdevel,
linuxppc-dev, Christoph Hellwig
In-Reply-To: <319d15b1-cb4a-a7b4-3082-12bb30eb5143@csgroup.eu>
On Tue, Aug 18, 2020 at 07:46:22PM +0200, Christophe Leroy wrote:
> I gave it a go on my powerpc mpc832x. I tested it on top of my newest
> series that reworks the 32 bits signal handlers (see
> https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=196278) with
> the microbenchmark test used is that series.
>
> With KUAP activated, on top of signal32 rework, performance is boosted as
> system time for the microbenchmark goes from 1.73s down to 1.56s, that is
> 10% quicker
>
> Surprisingly, with the kernel as is today without my signal's series, your
> series degrades performance slightly (from 2.55s to 2.64s ie 3.5% slower).
>
>
> I also observe, in both cases, a degradation on
>
> dd if=/dev/zero of=/dev/null count=1M
>
> Without your series, it runs in 5.29 seconds.
> With your series, it runs in 5.82 seconds, that is 10% more time.
That's pretty strage, I wonder if some kernel text cache line
effects come into play here?
The kernel access side is only used in slow path code, so it should
not make a difference, and the uaccess code is simplified and should be
(marginally) faster.
Btw, was this with the __{get,put}_user_allowed cockup that you noticed
fixed?
^ permalink raw reply
* Re: remove the last set_fs() in common code, and remove it for x86 and powerpc
From: Christophe Leroy @ 2020-08-18 17:46 UTC (permalink / raw)
To: Christoph Hellwig, Al Viro, Michael Ellerman, x86
Cc: linux-fsdevel, linux-arch, linuxppc-dev, Kees Cook, linux-kernel
In-Reply-To: <20200817073212.830069-1-hch@lst.de>
Le 17/08/2020 à 09:32, Christoph Hellwig a écrit :
> Hi all,
>
> this series removes the last set_fs() used to force a kernel address
> space for the uaccess code in the kernel read/write/splice code, and then
> stops implementing the address space overrides entirely for x86 and
> powerpc.
>
> The file system part has been posted a few times, and the read/write side
> has been pretty much unchanced. For splice this series drops the
> conversion of the seq_file and sysctl code to the iter ops, and thus loses
> the splice support for them. The reasons for that is that it caused a lot
> of churn for not much use - splice for these small files really isn't much
> of a win, even if existing userspace uses it. All callers I found do the
> proper fallback, but if this turns out to be an issue the conversion can
> be resurrected.
I like this series.
I gave it a go on my powerpc mpc832x. I tested it on top of my newest
series that reworks the 32 bits signal handlers (see
https://patchwork.ozlabs.org/project/linuxppc-dev/list/?series=196278)
with the microbenchmark test used is that series.
With KUAP activated, on top of signal32 rework, performance is boosted
as system time for the microbenchmark goes from 1.73s down to 1.56s,
that is 10% quicker
Surprisingly, with the kernel as is today without my signal's series,
your series degrades performance slightly (from 2.55s to 2.64s ie 3.5%
slower).
I also observe, in both cases, a degradation on
dd if=/dev/zero of=/dev/null count=1M
Without your series, it runs in 5.29 seconds.
With your series, it runs in 5.82 seconds, that is 10% more time.
Christophe
>
> Besides x86 and powerpc I plan to eventually convert all other
> architectures, although this will be a slow process, starting with the
> easier ones once the infrastructure is merged. The process to convert
> architectures is roughtly:
>
> - ensure there is no set_fs(KERNEL_DS) left in arch specific code
> - implement __get_kernel_nofault and __put_kernel_nofault
> - remove the arch specific address limitation functionality
>
> Diffstat:
> arch/Kconfig | 3
> arch/alpha/Kconfig | 1
> arch/arc/Kconfig | 1
> arch/arm/Kconfig | 1
> arch/arm64/Kconfig | 1
> arch/c6x/Kconfig | 1
> arch/csky/Kconfig | 1
> arch/h8300/Kconfig | 1
> arch/hexagon/Kconfig | 1
> arch/ia64/Kconfig | 1
> arch/m68k/Kconfig | 1
> arch/microblaze/Kconfig | 1
> arch/mips/Kconfig | 1
> arch/nds32/Kconfig | 1
> arch/nios2/Kconfig | 1
> arch/openrisc/Kconfig | 1
> arch/parisc/Kconfig | 1
> arch/powerpc/include/asm/processor.h | 7 -
> arch/powerpc/include/asm/thread_info.h | 5 -
> arch/powerpc/include/asm/uaccess.h | 78 ++++++++-----------
> arch/powerpc/kernel/signal.c | 3
> arch/powerpc/lib/sstep.c | 6 -
> arch/riscv/Kconfig | 1
> arch/s390/Kconfig | 1
> arch/sh/Kconfig | 1
> arch/sparc/Kconfig | 1
> arch/um/Kconfig | 1
> arch/x86/ia32/ia32_aout.c | 1
> arch/x86/include/asm/page_32_types.h | 11 ++
> arch/x86/include/asm/page_64_types.h | 38 +++++++++
> arch/x86/include/asm/processor.h | 60 ---------------
> arch/x86/include/asm/thread_info.h | 2
> arch/x86/include/asm/uaccess.h | 26 ------
> arch/x86/kernel/asm-offsets.c | 3
> arch/x86/lib/getuser.S | 28 ++++---
> arch/x86/lib/putuser.S | 21 +++--
> arch/xtensa/Kconfig | 1
> drivers/char/mem.c | 16 ----
> drivers/misc/lkdtm/bugs.c | 2
> drivers/misc/lkdtm/core.c | 4 +
> drivers/misc/lkdtm/usercopy.c | 2
> fs/read_write.c | 69 ++++++++++-------
> fs/splice.c | 130 +++------------------------------
> include/linux/fs.h | 2
> include/linux/uaccess.h | 18 ++++
> lib/test_bitmap.c | 10 ++
> 46 files changed, 235 insertions(+), 332 deletions(-)
>
^ permalink raw reply
* [PATCH v2 25/25] powerpc/signal32: Transform save_user_regs() and save_tm_user_regs() in 'unsafe' version
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Change those two functions to be used within a user access block.
For that, change save_general_regs() to and unsafe_save_general_regs(),
then replace all user accesses by unsafe_ versions.
This series leads to a reduction from 2.55s to 1.73s of
the system CPU time with the following microbench app
on an mpc832x with KUAP (approx 32%)
Without KUAP, the difference is in the noise.
void sigusr1(int sig) { }
int main(int argc, char **argv)
{
int i = 100000;
signal(SIGUSR1, sigusr1);
for (;i--;)
raise(SIGUSR1);
exit(0);
}
An additional 0.10s reduction is achieved by removing
CONFIG_PPC_FPU, as the mpc832x has no FPU.
A bit less spectacular on an 8xx as KUAP is less heavy, prior to
the series (with KUAP) it ran in 8.10 ms. Once applies the removal
of FPU regs handling, we get 7.05s. With the full series, we get 6.9s.
If artificially re-activating FPU regs handling with the full series,
we get 7.6s.
So for the 8xx, the removal of the FPU regs copy is what makes the
difference, but the rework of handle_signal also have a benefit.
Same as above, without KUAP the difference is in the noise.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 224 ++++++++++++++++----------------
1 file changed, 111 insertions(+), 113 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 86539a4e0514..f795fe0240a1 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -93,8 +93,8 @@ static inline int get_sigset_t(sigset_t *set,
#define to_user_ptr(p) ptr_to_compat(p)
#define from_user_ptr(p) compat_ptr(p)
-static inline int save_general_regs(struct pt_regs *regs,
- struct mcontext __user *frame)
+static __always_inline int
+save_general_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame)
{
elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
int val, i;
@@ -108,10 +108,12 @@ static inline int save_general_regs(struct pt_regs *regs,
else
val = gregs[i];
- if (__put_user(val, &frame->mc_gregs[i]))
- return -EFAULT;
+ unsafe_put_user(val, &frame->mc_gregs[i], failed);
}
return 0;
+
+failed:
+ return 1;
}
static inline int restore_general_regs(struct pt_regs *regs,
@@ -148,11 +150,15 @@ static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
#define to_user_ptr(p) ((unsigned long)(p))
#define from_user_ptr(p) ((void __user *)(p))
-static inline int save_general_regs(struct pt_regs *regs,
- struct mcontext __user *frame)
+static __always_inline int
+save_general_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame)
{
WARN_ON(!FULL_REGS(regs));
- return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
+ unsafe_copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE, failed);
+ return 0;
+
+failed:
+ return 1;
}
static inline int restore_general_regs(struct pt_regs *regs,
@@ -170,6 +176,11 @@ static inline int restore_general_regs(struct pt_regs *regs,
}
#endif
+#define unsafe_save_general_regs(regs, frame, label) do { \
+ if (save_general_regs_unsafe(regs, frame)) \
+ goto label; \
+} while (0)
+
/*
* When we have signals to deliver, we set up on the
* user stack, going down from the original stack pointer:
@@ -249,21 +260,19 @@ static void prepare_save_user_regs(int ctx_has_vsx_region)
#endif
}
-static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
- struct mcontext __user *tm_frame, int ctx_has_vsx_region)
+static int save_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, int ctx_has_vsx_region)
{
unsigned long msr = regs->msr;
/* save general registers */
- if (save_general_regs(regs, frame))
- return 1;
+ unsafe_save_general_regs(regs, frame, failed);
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
/* set MSR_VEC in the saved MSR value to indicate that
frame->mc_vregs contains valid data */
msr |= MSR_VEC;
@@ -276,11 +285,10 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* most significant bits of that same vector. --BenH
* Note that the current VRSAVE value is in the SPR at this point.
*/
- if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
- return 1;
+ unsafe_put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32],
+ failed);
#endif /* CONFIG_ALTIVEC */
- if (copy_fpr_to_user(&frame->mc_fregs, current))
- return 1;
+ unsafe_copy_fpr_to_user(&frame->mc_fregs, current, failed);
/*
* Clear the MSR VSX bit to indicate there is no valid state attached
@@ -295,17 +303,15 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* contains valid data
*/
if (current->thread.used_vsr && ctx_has_vsx_region) {
- if (copy_vsx_to_user(&frame->mc_vsregs, current))
- return 1;
+ unsafe_copy_vsx_to_user(&frame->mc_vsregs, current, failed);
msr |= MSR_VSX;
}
#endif /* CONFIG_VSX */
#ifdef CONFIG_SPE
/* save spe registers */
if (current->thread.used_spe) {
- if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
- ELF_NEVRREG * sizeof(u32)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
+ ELF_NEVRREG * sizeof(u32)), failed);
/* set MSR_SPE in the saved MSR value to indicate that
frame->mc_vregs contains valid data */
msr |= MSR_SPE;
@@ -313,21 +319,29 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
/* else assert((regs->msr & MSR_SPE) == 0) */
/* We always copy to/from spefscr */
- if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
- return 1;
+ unsafe_put_user(current->thread.spefscr,
+ (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
#endif /* CONFIG_SPE */
- if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
+
/* We need to write 0 the MSR top 32 bits in the tm frame so that we
* can check it on the restore to see if TM is active
*/
- if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
- return 1;
+ if (tm_frame)
+ unsafe_put_user(0, &tm_frame->mc_gregs[PT_MSR], failed);
return 0;
+
+failed:
+ return 1;
}
+#define unsafe_save_user_regs(regs, frame, tm_frame, has_vsx, label) do { \
+ if (save_user_regs_unsafe(regs, frame, tm_frame, has_vsx)) \
+ goto label; \
+} while (0)
+
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
/*
* Save the current user registers on the user stack.
@@ -336,7 +350,7 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* We also save the transactional registers to a second ucontext in the
* frame.
*
- * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
+ * See save_user_regs_unsafe() and signal_64.c:setup_tm_sigcontexts().
*/
static void prepare_save_tm_user_regs(void)
{
@@ -352,13 +366,12 @@ static void prepare_save_tm_user_regs(void)
#endif
}
-static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
- struct mcontext __user *tm_frame, unsigned long msr)
+static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, unsigned long msr)
{
/* Save both sets of general registers */
- if (save_general_regs(¤t->thread.ckpt_regs, frame)
- || save_general_regs(regs, tm_frame))
- return 1;
+ unsafe_save_general_regs(¤t->thread.ckpt_regs, frame, failed);
+ unsafe_save_general_regs(regs, tm_frame, failed);
/* Stash the top half of the 64bit MSR into the 32bit MSR word
* of the transactional mcontext. This way we have a backward-compatible
@@ -366,26 +379,21 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* also look at what type of transaction (T or S) was active at the
* time of the signal.
*/
- if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR], failed);
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- if (__copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- if (msr & MSR_VEC) {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.vr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- } else {
- if (__copy_to_user(&tm_frame->mc_vregs,
- ¤t->thread.ckvr_state,
- ELF_NVRREG * sizeof(vector128)))
- return 1;
- }
+ unsafe_copy_to_user(&frame->mc_vregs, ¤t->thread.ckvr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
+ if (msr & MSR_VEC)
+ unsafe_copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.vr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
+ else
+ unsafe_copy_to_user(&tm_frame->mc_vregs,
+ ¤t->thread.ckvr_state,
+ ELF_NVRREG * sizeof(vector128), failed);
/* set MSR_VEC in the saved MSR value to indicate that
* frame->mc_vregs contains valid data
@@ -398,29 +406,21 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* significant bits of a vector, we "cheat" and stuff VRSAVE in the
* most significant bits of that same vector. --BenH
*/
- if (__put_user(current->thread.ckvrsave,
- (u32 __user *)&frame->mc_vregs[32]))
- return 1;
- if (msr & MSR_VEC) {
- if (__put_user(current->thread.vrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- } else {
- if (__put_user(current->thread.ckvrsave,
- (u32 __user *)&tm_frame->mc_vregs[32]))
- return 1;
- }
+ unsafe_put_user(current->thread.ckvrsave,
+ (u32 __user *)&frame->mc_vregs[32], failed);
+ if (msr & MSR_VEC)
+ unsafe_put_user(current->thread.vrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32], failed);
+ else
+ unsafe_put_user(current->thread.ckvrsave,
+ (u32 __user *)&tm_frame->mc_vregs[32], failed);
#endif /* CONFIG_ALTIVEC */
- if (copy_ckfpr_to_user(&frame->mc_fregs, current))
- return 1;
- if (msr & MSR_FP) {
- if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- } else {
- if (copy_ckfpr_to_user(&tm_frame->mc_fregs, current))
- return 1;
- }
+ unsafe_copy_ckfpr_to_user(&frame->mc_fregs, current, failed);
+ if (msr & MSR_FP)
+ unsafe_copy_fpr_to_user(&tm_frame->mc_fregs, current, failed);
+ else
+ unsafe_copy_ckfpr_to_user(&tm_frame->mc_fregs, current, failed);
#ifdef CONFIG_VSX
/*
@@ -430,53 +430,54 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* contains valid data
*/
if (current->thread.used_vsr) {
- if (copy_ckvsx_to_user(&frame->mc_vsregs, current))
- return 1;
- if (msr & MSR_VSX) {
- if (copy_vsx_to_user(&tm_frame->mc_vsregs,
- current))
- return 1;
- } else {
- if (copy_ckvsx_to_user(&tm_frame->mc_vsregs, current))
- return 1;
- }
+ unsafe_copy_ckvsx_to_user(&frame->mc_vsregs, current, failed);
+ if (msr & MSR_VSX)
+ unsafe_copy_vsx_to_user(&tm_frame->mc_vsregs, current, failed);
+ else
+ unsafe_copy_ckvsx_to_user(&tm_frame->mc_vsregs, current, failed);
msr |= MSR_VSX;
}
#endif /* CONFIG_VSX */
#ifdef CONFIG_SPE
/* SPE regs are not checkpointed with TM, so this section is
- * simply the same as in save_user_regs().
+ * simply the same as in save_user_regs_unsafe().
*/
if (current->thread.used_spe) {
- if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
- ELF_NEVRREG * sizeof(u32)))
- return 1;
+ unsafe_copy_to_user(&frame->mc_vregs, current->thread.evr,
+ ELF_NEVRREG * sizeof(u32), failed);
/* set MSR_SPE in the saved MSR value to indicate that
* frame->mc_vregs contains valid data */
msr |= MSR_SPE;
}
/* We always copy to/from spefscr */
- if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
- return 1;
+ unsafe_put_user(current->thread.spefscr,
+ (u32 __user *)&frame->mc_vregs + ELF_NEVRREG, failed);
#endif /* CONFIG_SPE */
- if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
- return 1;
+ unsafe_put_user(msr, &frame->mc_gregs[PT_MSR], failed);
return 0;
+
+failed:
+ return 1;
}
#else
static void prepare_save_tm_user_regs(void) { }
-static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
- struct mcontext __user *tm_frame, unsigned long msr)
+static int save_tm_user_regs_unsafe(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, unsigned long msr)
{
return 0;
}
#endif
+#define unsafe_save_tm_user_regs(regs, frame, tm_frame, msr, label) do { \
+ if (save_tm_user_regs_unsafe(regs, frame, tm_frame, msr)) \
+ goto label; \
+} while (0)
+
/*
* Restore the current user register values from the user stack,
* (except for MSR).
@@ -769,6 +770,11 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_mctx = &frame->uc_transact.uc_mcontext;
#endif
+ if (MSR_TM_ACTIVE(msr))
+ prepare_save_tm_user_regs();
+ else
+ prepare_save_user_regs(1);
+
if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
@@ -788,8 +794,10 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
unsafe_put_user((unsigned long)tm_mctx,
&frame->uc_transact.uc_regs, failed);
#endif
+ unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
} else {
unsafe_put_user(0, &frame->uc.uc_link, failed);
+ unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
}
/* Save user registers on the stack */
@@ -812,15 +820,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
if (tramp == (unsigned long)mctx->mc_pad)
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
- if (MSR_TM_ACTIVE(msr)) {
- prepare_save_tm_user_regs();
- if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
- goto badframe;
- } else {
- prepare_save_user_regs(1);
- if (save_user_regs(regs, mctx, tm_mctx, 1))
- goto badframe;
- }
regs->link = tramp;
#ifdef CONFIG_PPC_FPU_REGS
@@ -875,6 +874,11 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_mctx = &frame->mctx_transact;
#endif
+ if (MSR_TM_ACTIVE(msr))
+ prepare_save_tm_user_regs();
+ else
+ prepare_save_user_regs(1);
+
if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
@@ -892,6 +896,11 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
unsafe_put_user(to_user_ptr(mctx), &sc->regs, failed);
unsafe_put_user(ksig->sig, &sc->signal, failed);
+ if (MSR_TM_ACTIVE(msr))
+ unsafe_save_tm_user_regs(regs, mctx, tm_mctx, msr, failed);
+ else
+ unsafe_save_user_regs(regs, mctx, tm_mctx, 1, failed);
+
if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
} else {
@@ -905,16 +914,6 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
if (tramp == (unsigned long)mctx->mc_pad)
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
- if (MSR_TM_ACTIVE(msr)) {
- prepare_save_tm_user_regs();
- if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
- goto badframe;
- } else {
- prepare_save_user_regs(1);
- if (save_user_regs(regs, mctx, tm_mctx, 1))
- goto badframe;
- }
-
regs->link = tramp;
#ifdef CONFIG_PPC_FPU_REGS
@@ -1066,10 +1065,9 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
prepare_save_user_regs(ctx_has_vsx_region);
- if (save_user_regs(regs, mctx, NULL, ctx_has_vsx_region))
- return -EFAULT;
if (!user_write_access_begin(old_ctx, ctx_size))
return -EFAULT;
+ unsafe_save_user_regs(regs, mctx, NULL, ctx_has_vsx_region, failed);
unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
user_write_access_end();
--
2.25.0
^ permalink raw reply related
* [PATCH v2 24/25] powerpc/signal32: Isolate non-copy actions in save_user_regs() and save_tm_user_regs()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Reorder actions in save_user_regs() and save_tm_user_regs() to
regroup copies together in order to switch to user_access_begin()
logic in a later patch.
Move non-copy actions into new functions called
prepare_save_user_regs() and prepare_save_tm_user_regs().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 54 +++++++++++++++++++++++++--------
1 file changed, 41 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 5b8a4ede142c..86539a4e0514 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -229,14 +229,31 @@ struct rt_sigframe {
* We only save the altivec/spe registers if the process has used
* altivec/spe instructions at some point.
*/
+static void prepare_save_user_regs(int ctx_has_vsx_region)
+{
+ /* Make sure floating point registers are stored in regs */
+ flush_fp_to_thread(current);
+#ifdef CONFIG_ALTIVEC
+ if (current->thread.used_vr)
+ flush_altivec_to_thread(current);
+ if (cpu_has_feature(CPU_FTR_ALTIVEC))
+ current->thread.vrsave = mfspr(SPRN_VRSAVE);
+#endif
+#ifdef CONFIG_VSX
+ if (current->thread.used_vsr && ctx_has_vsx_region)
+ flush_vsx_to_thread(current);
+#endif
+#ifdef CONFIG_SPE
+ if (current->thread.used_spe)
+ flush_spe_to_thread(current);
+#endif
+}
+
static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
struct mcontext __user *tm_frame, int ctx_has_vsx_region)
{
unsigned long msr = regs->msr;
- /* Make sure floating point registers are stored in regs */
- flush_fp_to_thread(current);
-
/* save general registers */
if (save_general_regs(regs, frame))
return 1;
@@ -244,7 +261,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#ifdef CONFIG_ALTIVEC
/* save altivec registers */
if (current->thread.used_vr) {
- flush_altivec_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state,
ELF_NVRREG * sizeof(vector128)))
return 1;
@@ -260,8 +276,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* most significant bits of that same vector. --BenH
* Note that the current VRSAVE value is in the SPR at this point.
*/
- if (cpu_has_feature(CPU_FTR_ALTIVEC))
- current->thread.vrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
return 1;
#endif /* CONFIG_ALTIVEC */
@@ -281,7 +295,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* contains valid data
*/
if (current->thread.used_vsr && ctx_has_vsx_region) {
- flush_vsx_to_thread(current);
if (copy_vsx_to_user(&frame->mc_vsregs, current))
return 1;
msr |= MSR_VSX;
@@ -290,7 +303,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#ifdef CONFIG_SPE
/* save spe registers */
if (current->thread.used_spe) {
- flush_spe_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
ELF_NEVRREG * sizeof(u32)))
return 1;
@@ -326,11 +338,23 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
*
* See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
*/
-static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
- struct mcontext __user *tm_frame, unsigned long msr)
+static void prepare_save_tm_user_regs(void)
{
WARN_ON(tm_suspend_disabled);
+#ifdef CONFIG_ALTIVEC
+ if (cpu_has_feature(CPU_FTR_ALTIVEC))
+ current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
+#endif
+#ifdef CONFIG_SPE
+ if (current->thread.used_spe)
+ flush_spe_to_thread(current);
+#endif
+}
+
+static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, unsigned long msr)
+{
/* Save both sets of general registers */
if (save_general_regs(¤t->thread.ckpt_regs, frame)
|| save_general_regs(regs, tm_frame))
@@ -374,8 +398,6 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* significant bits of a vector, we "cheat" and stuff VRSAVE in the
* most significant bits of that same vector. --BenH
*/
- if (cpu_has_feature(CPU_FTR_ALTIVEC))
- current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.ckvrsave,
(u32 __user *)&frame->mc_vregs[32]))
return 1;
@@ -427,7 +449,6 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* simply the same as in save_user_regs().
*/
if (current->thread.used_spe) {
- flush_spe_to_thread(current);
if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
ELF_NEVRREG * sizeof(u32)))
return 1;
@@ -447,6 +468,8 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
return 0;
}
#else
+static void prepare_save_tm_user_regs(void) { }
+
static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
struct mcontext __user *tm_frame, unsigned long msr)
{
@@ -790,9 +813,11 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
if (MSR_TM_ACTIVE(msr)) {
+ prepare_save_tm_user_regs();
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
} else {
+ prepare_save_user_regs(1);
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@@ -881,9 +906,11 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
if (MSR_TM_ACTIVE(msr)) {
+ prepare_save_tm_user_regs();
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
} else {
+ prepare_save_user_regs(1);
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@@ -1038,6 +1065,7 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
*/
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
+ prepare_save_user_regs(ctx_has_vsx_region);
if (save_user_regs(regs, mctx, NULL, ctx_has_vsx_region))
return -EFAULT;
if (!user_write_access_begin(old_ctx, ctx_size))
--
2.25.0
^ permalink raw reply related
* [PATCH v2 23/25] powerpc/signal: Create 'unsafe' versions of copy_[ck][fpr/vsx]_to_user()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
For the non VSX version, that's trivial. Just use unsafe_copy_to_user()
instead of __copy_to_user().
For the VSX version, remove the intermediate step through a buffer and
use unsafe_put_user() directly. This generates a far smaller code which
is acceptable to inline, see below:
Standard VSX version:
0000000000000000 <.copy_fpr_to_user>:
0: 7c 08 02 a6 mflr r0
4: fb e1 ff f8 std r31,-8(r1)
8: 39 00 00 20 li r8,32
c: 39 24 0b 80 addi r9,r4,2944
10: 7d 09 03 a6 mtctr r8
14: f8 01 00 10 std r0,16(r1)
18: f8 21 fe 71 stdu r1,-400(r1)
1c: 39 41 00 68 addi r10,r1,104
20: e9 09 00 00 ld r8,0(r9)
24: 39 4a 00 08 addi r10,r10,8
28: 39 29 00 10 addi r9,r9,16
2c: f9 0a 00 00 std r8,0(r10)
30: 42 00 ff f0 bdnz 20 <.copy_fpr_to_user+0x20>
34: e9 24 0d 80 ld r9,3456(r4)
38: 3d 42 00 00 addis r10,r2,0
3a: R_PPC64_TOC16_HA .toc
3c: eb ea 00 00 ld r31,0(r10)
3e: R_PPC64_TOC16_LO_DS .toc
40: f9 21 01 70 std r9,368(r1)
44: e9 3f 00 00 ld r9,0(r31)
48: 81 29 00 20 lwz r9,32(r9)
4c: 2f 89 00 00 cmpwi cr7,r9,0
50: 40 9c 00 18 bge cr7,68 <.copy_fpr_to_user+0x68>
54: 4c 00 01 2c isync
58: 3d 20 40 00 lis r9,16384
5c: 79 29 07 c6 rldicr r9,r9,32,31
60: 7d 3d 03 a6 mtspr 29,r9
64: 4c 00 01 2c isync
68: 38 a0 01 08 li r5,264
6c: 38 81 00 70 addi r4,r1,112
70: 48 00 00 01 bl 70 <.copy_fpr_to_user+0x70>
70: R_PPC64_REL24 .__copy_tofrom_user
74: 60 00 00 00 nop
78: e9 3f 00 00 ld r9,0(r31)
7c: 81 29 00 20 lwz r9,32(r9)
80: 2f 89 00 00 cmpwi cr7,r9,0
84: 40 9c 00 18 bge cr7,9c <.copy_fpr_to_user+0x9c>
88: 4c 00 01 2c isync
8c: 39 20 ff ff li r9,-1
90: 79 29 00 44 rldicr r9,r9,0,1
94: 7d 3d 03 a6 mtspr 29,r9
98: 4c 00 01 2c isync
9c: 38 21 01 90 addi r1,r1,400
a0: e8 01 00 10 ld r0,16(r1)
a4: eb e1 ff f8 ld r31,-8(r1)
a8: 7c 08 03 a6 mtlr r0
ac: 4e 80 00 20 blr
'unsafe' simulated VSX version (The ... are only nops) using
unsafe_copy_fpr_to_user() macro:
unsigned long copy_fpr_to_user(void __user *to,
struct task_struct *task)
{
unsafe_copy_fpr_to_user(to, task, failed);
return 0;
failed:
return 1;
}
0000000000000000 <.copy_fpr_to_user>:
0: 39 00 00 20 li r8,32
4: 39 44 0b 80 addi r10,r4,2944
8: 7d 09 03 a6 mtctr r8
c: 7c 69 1b 78 mr r9,r3
...
20: e9 0a 00 00 ld r8,0(r10)
24: f9 09 00 00 std r8,0(r9)
28: 39 4a 00 10 addi r10,r10,16
2c: 39 29 00 08 addi r9,r9,8
30: 42 00 ff f0 bdnz 20 <.copy_fpr_to_user+0x20>
34: e9 24 0d 80 ld r9,3456(r4)
38: f9 23 01 00 std r9,256(r3)
3c: 38 60 00 00 li r3,0
40: 4e 80 00 20 blr
...
50: 38 60 00 01 li r3,1
54: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.h | 53 ++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index f610cfafa478..2559a681536e 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -32,7 +32,54 @@ unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
+
+#define unsafe_copy_fpr_to_user(to, task, label) do { \
+ struct task_struct *__t = task; \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NFPREG - 1 ; i++) \
+ unsafe_put_user(__t->thread.TS_FPR(i), &buf[i], label); \
+ unsafe_put_user(__t->thread.fp_state.fpscr, &buf[i], label); \
+} while (0)
+
+#define unsafe_copy_vsx_to_user(to, task, label) do { \
+ struct task_struct *__t = task; \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NVSRHALFREG ; i++) \
+ unsafe_put_user(__t->thread.fp_state.fpr[i][TS_VSRLOWOFFSET], \
+ &buf[i], label);\
+} while (0)
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define unsafe_copy_ckfpr_to_user(to, task, label) do { \
+ struct task_struct *__t = task; \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NFPREG - 1 ; i++) \
+ unsafe_put_user(__t->thread.TS_CKFPR(i), &buf[i], label);\
+ unsafe_put_user(__t->thread.ckfp_state.fpscr, &buf[i], label); \
+} while (0)
+
+#define unsafe_copy_ckvsx_to_user(to, task, label) do { \
+ struct task_struct *__t = task; \
+ u64 __user *buf = (u64 __user *)to; \
+ int i; \
+ \
+ for (i = 0; i < ELF_NVSRHALFREG ; i++) \
+ unsafe_put_user(__t->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET], \
+ &buf[i], label);\
+} while (0)
+#endif
#elif defined(CONFIG_PPC_FPU_REGS)
+
+#define unsafe_copy_fpr_to_user(to, task, label) \
+ unsafe_copy_to_user(to, (task)->thread.fp_state.fpr, \
+ ELF_NFPREG * sizeof(double), label)
+
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
@@ -48,6 +95,10 @@ copy_fpr_from_user(struct task_struct *task, void __user *from)
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define unsafe_copy_ckfpr_to_user(to, task, label) \
+ unsafe_copy_to_user(to, (task)->thread.ckfp_state.fpr, \
+ ELF_NFPREG * sizeof(double), label)
+
inline unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task)
{
return __copy_to_user(to, task->thread.ckfp_state.fpr,
@@ -62,6 +113,8 @@ copy_ckfpr_from_user(struct task_struct *task, void __user *from)
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
#else
+#define unsafe_copy_fpr_to_user(to, task, label) do { } while (0)
+
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
--
2.25.0
^ permalink raw reply related
* [PATCH v2 22/25] powerpc/signal32: Switch swap_context() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
As this was the last user of put_sigset_t(), remove it as well.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 3f9f315dd036..5b8a4ede142c 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -82,11 +82,6 @@
* Functions for flipping sigsets (thanks to brain dead generic
* implementation that makes things simple for little endian only)
*/
-static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
-{
- return put_compat_sigset(uset, set, sizeof(*uset));
-}
-
#define unsafe_put_sigset_t unsafe_put_compat_sigset
static inline int get_sigset_t(sigset_t *set,
@@ -138,11 +133,6 @@ static inline int restore_general_regs(struct pt_regs *regs,
#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
-static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
-{
- return copy_to_user(uset, set, sizeof(*uset));
-}
-
#define unsafe_put_sigset_t(uset, set, label) do { \
sigset_t __user *__us = uset ; \
const sigset_t *__s = set; \
@@ -1048,11 +1038,13 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
*/
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
- if (!access_ok(old_ctx, ctx_size)
- || save_user_regs(regs, mctx, NULL, ctx_has_vsx_region)
- || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
- || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
+ if (save_user_regs(regs, mctx, NULL, ctx_has_vsx_region))
+ return -EFAULT;
+ if (!user_write_access_begin(old_ctx, ctx_size))
return -EFAULT;
+ unsafe_put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked, failed);
+ unsafe_put_user(to_user_ptr(mctx), &old_ctx->uc_regs, failed);
+ user_write_access_end();
}
if (new_ctx == NULL)
return 0;
@@ -1076,6 +1068,10 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
set_thread_flag(TIF_RESTOREALL);
return 0;
+
+failed:
+ user_write_access_end();
+ return -EFAULT;
}
#ifdef CONFIG_PPC64
--
2.25.0
^ permalink raw reply related
* [PATCH v2 21/25] powerpc/signal32: Add and use unsafe_put_sigset_t()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
put_sigset_t() calls copy_to_user() for copying two words.
This is terribly inefficient for copying two words.
By switching to unsafe_put_user(), we end up with something as
simple as:
3cc: 81 3d 00 00 lwz r9,0(r29)
3d0: 91 26 00 b4 stw r9,180(r6)
3d4: 81 3d 00 04 lwz r9,4(r29)
3d8: 91 26 00 b8 stw r9,184(r6)
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 310d3b8d9ad5..3f9f315dd036 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -87,6 +87,8 @@ static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
return put_compat_sigset(uset, set, sizeof(*uset));
}
+#define unsafe_put_sigset_t unsafe_put_compat_sigset
+
static inline int get_sigset_t(sigset_t *set,
const compat_sigset_t __user *uset)
{
@@ -141,6 +143,13 @@ static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
return copy_to_user(uset, set, sizeof(*uset));
}
+#define unsafe_put_sigset_t(uset, set, label) do { \
+ sigset_t __user *__us = uset ; \
+ const sigset_t *__s = set; \
+ \
+ unsafe_copy_to_user(__us, __s, sizeof(*__us), label); \
+} while (0)
+
static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset)
{
return copy_from_user(set, uset, sizeof(*uset));
@@ -780,10 +789,10 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
failed);
unsafe_put_user(PPC_INST_SC, &mctx->mc_pad[1], failed);
}
+ unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed);
+
user_write_access_end();
- if (put_sigset_t(&frame->uc.uc_sigmask, oldset))
- goto badframe;
if (copy_siginfo_to_user(&frame->info, &ksig->info))
goto badframe;
--
2.25.0
^ permalink raw reply related
* [PATCH v2 19/25] powerpc/signal32: Remove ifdefery in middle of if/else
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
MSR_TM_ACTIVE() is always defined and returns always 0 when
CONFIG_PPC_TRANSACTIONAL_MEM is not selected, so the awful
ifdefery in the middle of an if/else can be removed.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 93c2d6304831..310d3b8d9ad5 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -447,6 +447,12 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
return 0;
}
+#else
+static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, unsigned long msr)
+{
+ return 0;
+}
#endif
/*
@@ -732,10 +738,8 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
unsigned long newsp = 0;
unsigned long tramp;
struct pt_regs *regs = tsk->thread.regs;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
/* Save the thread's msr before get_tm_stackpointer() changes it */
unsigned long msr = regs->msr;
-#endif
/* Set up Signal Frame */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
@@ -786,14 +790,10 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
if (tramp == (unsigned long)mctx->mc_pad)
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (MSR_TM_ACTIVE(msr)) {
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
- }
- else
-#endif
- {
+ } else {
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@@ -842,10 +842,8 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
unsigned long newsp = 0;
unsigned long tramp;
struct pt_regs *regs = tsk->thread.regs;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
/* Save the thread's msr before get_tm_stackpointer() changes it */
unsigned long msr = regs->msr;
-#endif
/* Set up Signal Frame */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
@@ -883,14 +881,10 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
if (tramp == (unsigned long)mctx->mc_pad)
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (MSR_TM_ACTIVE(msr)) {
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
- }
- else
-#endif
- {
+ } else {
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
--
2.25.0
^ permalink raw reply related
* [PATCH v2 20/25] signal: Add unsafe_put_compat_sigset()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Implement 'unsafe' version of put_compat_sigset()
For the bigendian, use unsafe_put_user() directly
to avoid intermediate copy through the stack.
For the littleendian, use a straight unsafe_copy_to_user().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
include/linux/compat.h | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/include/linux/compat.h b/include/linux/compat.h
index d38c4d7e83bd..7ec6e44b093b 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -442,6 +442,38 @@ put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set,
#endif
}
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define unsafe_put_compat_sigset(compat, set, label) do { \
+ compat_sigset_t __user *__c = compat; \
+ const sigset_t *__s = set; \
+ \
+ switch (_NSIG_WORDS) { \
+ case 4: \
+ unsafe_put_user(__s->sig[3] >> 32, &__c->sig[7], label); \
+ unsafe_put_user(__s->sig[3], &__c->sig[6], label); \
+ fallthrough; \
+ case 3: \
+ unsafe_put_user(__s->sig[2] >> 32, &__c->sig[5], label); \
+ unsafe_put_user(__s->sig[2], &__c->sig[4], label); \
+ fallthrough; \
+ case 2: \
+ unsafe_put_user(__s->sig[1] >> 32, &__c->sig[3], label); \
+ unsafe_put_user(__s->sig[1], &__c->sig[2], label); \
+ fallthrough; \
+ case 1: \
+ unsafe_put_user(__s->sig[0] >> 32, &__c->sig[1], label); \
+ unsafe_put_user(__s->sig[0], &__c->sig[0], label); \
+ } \
+} while (0)
+#else
+#define unsafe_put_compat_sigset(compat, set, label) do { \
+ compat_sigset_t __user *__c = compat; \
+ const sigset_t *__s = set; \
+ \
+ unsafe_copy_to_user(__c, __s, sizeof(*__c), label); \
+} while (0)
+#endif
+
extern int compat_ptrace_request(struct task_struct *child,
compat_long_t request,
compat_ulong_t addr, compat_ulong_t data);
--
2.25.0
^ permalink raw reply related
* [PATCH v2 18/25] powerpc/signal32: Switch handle_rt_signal32() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
On the same way as handle_signal32(), replace all user
accesses with equivalent unsafe_ versions, and move the
trampoline code icache flush outside the user access block.
Functions that have no unsafe_ equivalent also remains outside
the access block.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 55 ++++++++++++++++++++-------------
1 file changed, 34 insertions(+), 21 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index fc8ba4b29edf..93c2d6304831 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -58,8 +58,6 @@
#define mcontext mcontext32
#define ucontext ucontext32
-#define __save_altstack __compat_save_altstack
-
/*
* Userspace code may pass a ucontext which doesn't include VSX added
* at the end. We need to check for this case.
@@ -745,16 +743,28 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_mctx = &frame->uc_transact.uc_mcontext;
#endif
- if (!access_ok(frame, sizeof(*frame)))
+ if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
- if (copy_siginfo_to_user(&frame->info, &ksig->info) ||
- __put_user(0, &frame->uc.uc_flags) ||
- __save_altstack(&frame->uc.uc_stack, regs->gpr[1]) ||
- __put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs) ||
- put_sigset_t(&frame->uc.uc_sigmask, oldset))
- goto badframe;
+ unsafe_put_user(0, &frame->uc.uc_flags, failed);
+#ifdef CONFIG_PPC64
+ unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
+#else
+ unsafe_save_altstack(&frame->uc.uc_stack, regs->gpr[1], failed);
+#endif
+ unsafe_put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs, failed);
+
+ if (MSR_TM_ACTIVE(msr)) {
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ unsafe_put_user((unsigned long)&frame->uc_transact,
+ &frame->uc.uc_link, failed);
+ unsafe_put_user((unsigned long)tm_mctx,
+ &frame->uc_transact.uc_regs, failed);
+#endif
+ } else {
+ unsafe_put_user(0, &frame->uc.uc_link, failed);
+ }
/* Save user registers on the stack */
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
@@ -762,28 +772,28 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
} else {
tramp = (unsigned long)mctx->mc_pad;
/* Set up the sigreturn trampoline: li r0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0]))
- goto badframe;
- if (__put_user(PPC_INST_SC, &mctx->mc_pad[1]))
- goto badframe;
- flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
+ unsafe_put_user(PPC_INST_ADDI + __NR_rt_sigreturn, &mctx->mc_pad[0],
+ failed);
+ unsafe_put_user(PPC_INST_SC, &mctx->mc_pad[1], failed);
}
+ user_write_access_end();
+
+ if (put_sigset_t(&frame->uc.uc_sigmask, oldset))
+ goto badframe;
+ if (copy_siginfo_to_user(&frame->info, &ksig->info))
+ goto badframe;
+
+ if (tramp == (unsigned long)mctx->mc_pad)
+ flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (MSR_TM_ACTIVE(msr)) {
- if (__put_user((unsigned long)&frame->uc_transact,
- &frame->uc.uc_link) ||
- __put_user((unsigned long)tm_mctx,
- &frame->uc_transact.uc_regs))
- goto badframe;
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
}
else
#endif
{
- if (__put_user(0, &frame->uc.uc_link))
- goto badframe;
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@@ -810,6 +820,9 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->msr |= (MSR_KERNEL & MSR_LE);
return 0;
+failed:
+ user_write_access_end();
+
badframe:
signal_fault(tsk, regs, "handle_rt_signal32", frame);
--
2.25.0
^ permalink raw reply related
* [PATCH v2 17/25] powerpc/signal32: Switch handle_signal32() to user_access_begin() logic
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Replace the access_ok() by user_access_begin() and change all user
accesses to unsafe_ version.
Move flush_icache_range() outside the user access block.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 29 ++++++++++++++++-------------
1 file changed, 16 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index d8c3843102df..fc8ba4b29edf 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -840,35 +840,35 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
tm_mctx = &frame->mctx_transact;
#endif
- if (!access_ok(frame, sizeof(*frame)))
+ if (!user_write_access_begin(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
#if _NSIG != 64
#error "Please adjust handle_signal()"
#endif
- if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
- || __put_user(oldset->sig[0], &sc->oldmask)
+ unsafe_put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler, failed);
+ unsafe_put_user(oldset->sig[0], &sc->oldmask, failed);
#ifdef CONFIG_PPC64
- || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+ unsafe_put_user((oldset->sig[0] >> 32), &sc->_unused[3], failed);
#else
- || __put_user(oldset->sig[1], &sc->_unused[3])
+ unsafe_put_user(oldset->sig[1], &sc->_unused[3], failed);
#endif
- || __put_user(to_user_ptr(mctx), &sc->regs)
- || __put_user(ksig->sig, &sc->signal))
- goto badframe;
+ unsafe_put_user(to_user_ptr(mctx), &sc->regs, failed);
+ unsafe_put_user(ksig->sig, &sc->signal, failed);
if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
} else {
tramp = (unsigned long)mctx->mc_pad;
/* Set up the sigreturn trampoline: li r0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0]))
- goto badframe;
- if (__put_user(PPC_INST_SC, &mctx->mc_pad[1]))
- goto badframe;
- flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
+ unsafe_put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0], failed);
+ unsafe_put_user(PPC_INST_SC, &mctx->mc_pad[1], failed);
}
+ user_write_access_end();
+
+ if (tramp == (unsigned long)mctx->mc_pad)
+ flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (MSR_TM_ACTIVE(msr)) {
@@ -901,6 +901,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->msr &= ~MSR_LE;
return 0;
+failed:
+ user_write_access_end();
+
badframe:
signal_fault(tsk, regs, "handle_signal32", frame);
--
2.25.0
^ permalink raw reply related
* [PATCH v2 16/25] powerpc/signal32: Move signal trampoline setup to handle_[rt_]signal32
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Move signal trampoline setup into handle_signal32()
and handle_rt_signal32().
At the same time, remove the define which hides the mc_pad field
used for trampoline.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 61 ++++++++++++---------------------
1 file changed, 22 insertions(+), 39 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index ab8c8cb98b15..d8c3843102df 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -199,9 +199,6 @@ struct sigframe {
int abigap[56];
};
-/* We use the mc_pad field for the signal return trampoline. */
-#define tramp mc_pad
-
/*
* When we have rt signals to deliver, we set up on the
* user stack, going down from the original stack pointer:
@@ -236,8 +233,7 @@ struct rt_sigframe {
* altivec/spe instructions at some point.
*/
static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
- struct mcontext __user *tm_frame, int sigret,
- int ctx_has_vsx_region)
+ struct mcontext __user *tm_frame, int ctx_has_vsx_region)
{
unsigned long msr = regs->msr;
@@ -320,15 +316,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR]))
return 1;
- if (sigret) {
- /* Set up the sigreturn trampoline: li 0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
- || __put_user(PPC_INST_SC, &frame->tramp[1]))
- return 1;
- flush_icache_range((unsigned long) &frame->tramp[0],
- (unsigned long) &frame->tramp[2]);
- }
-
return 0;
}
@@ -342,10 +329,8 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
*
* See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
*/
-static int save_tm_user_regs(struct pt_regs *regs,
- struct mcontext __user *frame,
- struct mcontext __user *tm_frame, int sigret,
- unsigned long msr)
+static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+ struct mcontext __user *tm_frame, unsigned long msr)
{
WARN_ON(tm_suspend_disabled);
@@ -461,14 +446,6 @@ static int save_tm_user_regs(struct pt_regs *regs,
if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
return 1;
- if (sigret) {
- /* Set up the sigreturn trampoline: li 0,sigret; sc */
- if (__put_user(PPC_INST_ADDI + sigret, &frame->tramp[0])
- || __put_user(PPC_INST_SC, &frame->tramp[1]))
- return 1;
- flush_icache_range((unsigned long) &frame->tramp[0],
- (unsigned long) &frame->tramp[2]);
- }
return 0;
}
@@ -755,7 +732,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct mcontext __user *mctx;
struct mcontext __user *tm_mctx = NULL;
unsigned long newsp = 0;
- int sigret;
unsigned long tramp;
struct pt_regs *regs = tsk->thread.regs;
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -782,11 +758,15 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Save user registers on the stack */
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
- sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
} else {
- sigret = __NR_rt_sigreturn;
- tramp = (unsigned long)mctx->tramp;
+ tramp = (unsigned long)mctx->mc_pad;
+ /* Set up the sigreturn trampoline: li r0,sigret; sc */
+ if (__put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0]))
+ goto badframe;
+ if (__put_user(PPC_INST_SC, &mctx->mc_pad[1]))
+ goto badframe;
+ flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -796,7 +776,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
__put_user((unsigned long)tm_mctx,
&frame->uc_transact.uc_regs))
goto badframe;
- if (save_tm_user_regs(regs, mctx, tm_mctx, sigret, msr))
+ if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
}
else
@@ -804,7 +784,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
{
if (__put_user(0, &frame->uc.uc_link))
goto badframe;
- if (save_user_regs(regs, mctx, tm_mctx, sigret, 1))
+ if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
regs->link = tramp;
@@ -847,7 +827,6 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
struct mcontext __user *mctx;
struct mcontext __user *tm_mctx = NULL;
unsigned long newsp = 0;
- int sigret;
unsigned long tramp;
struct pt_regs *regs = tsk->thread.regs;
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -880,22 +859,26 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
goto badframe;
if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
- sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
} else {
- sigret = __NR_sigreturn;
- tramp = (unsigned long)mctx->tramp;
+ tramp = (unsigned long)mctx->mc_pad;
+ /* Set up the sigreturn trampoline: li r0,sigret; sc */
+ if (__put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0]))
+ goto badframe;
+ if (__put_user(PPC_INST_SC, &mctx->mc_pad[1]))
+ goto badframe;
+ flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
if (MSR_TM_ACTIVE(msr)) {
- if (save_tm_user_regs(regs, mctx, tm_mctx, sigret, msr))
+ if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
}
else
#endif
{
- if (save_user_regs(regs, mctx, tm_mctx, sigret, 1))
+ if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@@ -1047,7 +1030,7 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
if (!access_ok(old_ctx, ctx_size)
- || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region)
+ || save_user_regs(regs, mctx, NULL, ctx_has_vsx_region)
|| put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked)
|| __put_user(to_user_ptr(mctx), &old_ctx->uc_regs))
return -EFAULT;
--
2.25.0
^ permalink raw reply related
* [PATCH v2 15/25] powerpc/signal32: Misc changes to make handle_[rt_]_signal32() more similar
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Miscellaneous changes to clean and make handle_signal32() and
handle_rt_signal32() even more similar.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index d0fcb3de66aa..ab8c8cb98b15 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -764,8 +764,11 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
#endif
/* Set up Signal Frame */
- /* Put a Real Time Context onto stack */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
+ mctx = &frame->uc.uc_mcontext;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ tm_mctx = &frame->uc_transact.uc_mcontext;
+#endif
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
@@ -778,7 +781,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
goto badframe;
/* Save user registers on the stack */
- mctx = &frame->uc.uc_mcontext;
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
@@ -788,7 +790,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- tm_mctx = &frame->uc_transact.uc_mcontext;
if (MSR_TM_ACTIVE(msr)) {
if (__put_user((unsigned long)&frame->uc_transact,
&frame->uc.uc_link) ||
@@ -843,6 +844,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
{
struct sigcontext __user *sc;
struct sigframe __user *frame;
+ struct mcontext __user *mctx;
struct mcontext __user *tm_mctx = NULL;
unsigned long newsp = 0;
int sigret;
@@ -855,6 +857,10 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
+ mctx = &frame->mctx;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ tm_mctx = &frame->mctx_transact;
+#endif
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
@@ -869,7 +875,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
#else
|| __put_user(oldset->sig[1], &sc->_unused[3])
#endif
- || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
+ || __put_user(to_user_ptr(mctx), &sc->regs)
|| __put_user(ksig->sig, &sc->signal))
goto badframe;
@@ -878,20 +884,18 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
} else {
sigret = __NR_sigreturn;
- tramp = (unsigned long) frame->mctx.tramp;
+ tramp = (unsigned long)mctx->tramp;
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- tm_mctx = &frame->mctx_transact;
if (MSR_TM_ACTIVE(msr)) {
- if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
- sigret, msr))
+ if (save_tm_user_regs(regs, mctx, tm_mctx, sigret, msr))
goto badframe;
}
else
#endif
{
- if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
+ if (save_user_regs(regs, mctx, tm_mctx, sigret, 1))
goto badframe;
}
@@ -909,7 +913,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->gpr[1] = newsp;
regs->gpr[3] = ksig->sig;
regs->gpr[4] = (unsigned long) sc;
- regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
+ regs->nip = (unsigned long)ksig->ka.sa.sa_handler;
/* enter the signal handler in big-endian mode */
regs->msr &= ~MSR_LE;
return 0;
--
2.25.0
^ permalink raw reply related
* [PATCH v2 14/25] powerpc/signal32: Rename local pointers in handle_rt_signal32()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Rename pointers in handle_rt_signal32() to make it more similar to
handle_signal32()
tm_frame becomes tm_mctx
frame becomes mctx
rt_sf becomes frame
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 51 ++++++++++++++++-----------------
1 file changed, 25 insertions(+), 26 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 2cc686b9f566..d0fcb3de66aa 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -751,9 +751,9 @@ static long restore_tm_user_regs(struct pt_regs *regs,
int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk)
{
- struct rt_sigframe __user *rt_sf;
- struct mcontext __user *frame;
- struct mcontext __user *tm_frame = NULL;
+ struct rt_sigframe __user *frame;
+ struct mcontext __user *mctx;
+ struct mcontext __user *tm_mctx = NULL;
unsigned long newsp = 0;
int sigret;
unsigned long tramp;
@@ -765,46 +765,45 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
- rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
- if (!access_ok(rt_sf, sizeof(*rt_sf)))
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
+ if (!access_ok(frame, sizeof(*frame)))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
- if (copy_siginfo_to_user(&rt_sf->info, &ksig->info)
- || __put_user(0, &rt_sf->uc.uc_flags)
- || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1])
- || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
- &rt_sf->uc.uc_regs)
- || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
+ if (copy_siginfo_to_user(&frame->info, &ksig->info) ||
+ __put_user(0, &frame->uc.uc_flags) ||
+ __save_altstack(&frame->uc.uc_stack, regs->gpr[1]) ||
+ __put_user(to_user_ptr(&frame->uc.uc_mcontext), &frame->uc.uc_regs) ||
+ put_sigset_t(&frame->uc.uc_sigmask, oldset))
goto badframe;
/* Save user registers on the stack */
- frame = &rt_sf->uc.uc_mcontext;
+ mctx = &frame->uc.uc_mcontext;
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
} else {
sigret = __NR_rt_sigreturn;
- tramp = (unsigned long) frame->tramp;
+ tramp = (unsigned long)mctx->tramp;
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- tm_frame = &rt_sf->uc_transact.uc_mcontext;
+ tm_mctx = &frame->uc_transact.uc_mcontext;
if (MSR_TM_ACTIVE(msr)) {
- if (__put_user((unsigned long)&rt_sf->uc_transact,
- &rt_sf->uc.uc_link) ||
- __put_user((unsigned long)tm_frame,
- &rt_sf->uc_transact.uc_regs))
+ if (__put_user((unsigned long)&frame->uc_transact,
+ &frame->uc.uc_link) ||
+ __put_user((unsigned long)tm_mctx,
+ &frame->uc_transact.uc_regs))
goto badframe;
- if (save_tm_user_regs(regs, frame, tm_frame, sigret, msr))
+ if (save_tm_user_regs(regs, mctx, tm_mctx, sigret, msr))
goto badframe;
}
else
#endif
{
- if (__put_user(0, &rt_sf->uc.uc_link))
+ if (__put_user(0, &frame->uc.uc_link))
goto badframe;
- if (save_user_regs(regs, frame, tm_frame, sigret, 1))
+ if (save_user_regs(regs, mctx, tm_mctx, sigret, 1))
goto badframe;
}
regs->link = tramp;
@@ -814,16 +813,16 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
#endif
/* create a stack frame for the caller of the handler */
- newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
+ newsp = ((unsigned long)frame) - (__SIGNAL_FRAMESIZE + 16);
if (put_user(regs->gpr[1], (u32 __user *)newsp))
goto badframe;
/* Fill registers for signal handler */
regs->gpr[1] = newsp;
regs->gpr[3] = ksig->sig;
- regs->gpr[4] = (unsigned long) &rt_sf->info;
- regs->gpr[5] = (unsigned long) &rt_sf->uc;
- regs->gpr[6] = (unsigned long) rt_sf;
+ regs->gpr[4] = (unsigned long)&frame->info;
+ regs->gpr[5] = (unsigned long)&frame->uc;
+ regs->gpr[6] = (unsigned long)frame;
regs->nip = (unsigned long) ksig->ka.sa.sa_handler;
/* enter the signal handler in native-endian mode */
regs->msr &= ~MSR_LE;
@@ -831,7 +830,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- signal_fault(tsk, regs, "handle_rt_signal32", rt_sf);
+ signal_fault(tsk, regs, "handle_rt_signal32", frame);
return 1;
}
--
2.25.0
^ permalink raw reply related
* [PATCH v2 13/25] powerpc/signal32: Move handle_signal32() close to handle_rt_signal32()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Those two functions are similar and serving the same purpose.
To ease refactorisation, move them close to each other.
This is pure move, no code change, no cosmetic. Yes, checkpatch is
not happy, most will clear later.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 170 ++++++++++++++++----------------
1 file changed, 85 insertions(+), 85 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 44a46911ff98..2cc686b9f566 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -836,6 +836,91 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 1;
}
+/*
+ * OK, we're invoking a handler
+ */
+int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
+ struct task_struct *tsk)
+{
+ struct sigcontext __user *sc;
+ struct sigframe __user *frame;
+ struct mcontext __user *tm_mctx = NULL;
+ unsigned long newsp = 0;
+ int sigret;
+ unsigned long tramp;
+ struct pt_regs *regs = tsk->thread.regs;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ /* Save the thread's msr before get_tm_stackpointer() changes it */
+ unsigned long msr = regs->msr;
+#endif
+
+ /* Set up Signal Frame */
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ sc = (struct sigcontext __user *) &frame->sctx;
+
+#if _NSIG != 64
+#error "Please adjust handle_signal()"
+#endif
+ if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
+ || __put_user(oldset->sig[0], &sc->oldmask)
+#ifdef CONFIG_PPC64
+ || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+#else
+ || __put_user(oldset->sig[1], &sc->_unused[3])
+#endif
+ || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
+ || __put_user(ksig->sig, &sc->signal))
+ goto badframe;
+
+ if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
+ sigret = 0;
+ tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
+ } else {
+ sigret = __NR_sigreturn;
+ tramp = (unsigned long) frame->mctx.tramp;
+ }
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ tm_mctx = &frame->mctx_transact;
+ if (MSR_TM_ACTIVE(msr)) {
+ if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
+ sigret, msr))
+ goto badframe;
+ }
+ else
+#endif
+ {
+ if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
+ goto badframe;
+ }
+
+ regs->link = tramp;
+
+#ifdef CONFIG_PPC_FPU_REGS
+ tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
+#endif
+
+ /* create a stack frame for the caller of the handler */
+ newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
+ if (put_user(regs->gpr[1], (u32 __user *)newsp))
+ goto badframe;
+
+ regs->gpr[1] = newsp;
+ regs->gpr[3] = ksig->sig;
+ regs->gpr[4] = (unsigned long) sc;
+ regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
+ /* enter the signal handler in big-endian mode */
+ regs->msr &= ~MSR_LE;
+ return 0;
+
+badframe:
+ signal_fault(tsk, regs, "handle_signal32", frame);
+
+ return 1;
+}
+
static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
{
sigset_t set;
@@ -1188,91 +1273,6 @@ SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
}
#endif
-/*
- * OK, we're invoking a handler
- */
-int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
- struct task_struct *tsk)
-{
- struct sigcontext __user *sc;
- struct sigframe __user *frame;
- struct mcontext __user *tm_mctx = NULL;
- unsigned long newsp = 0;
- int sigret;
- unsigned long tramp;
- struct pt_regs *regs = tsk->thread.regs;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- /* Save the thread's msr before get_tm_stackpointer() changes it */
- unsigned long msr = regs->msr;
-#endif
-
- /* Set up Signal Frame */
- frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
- if (!access_ok(frame, sizeof(*frame)))
- goto badframe;
- sc = (struct sigcontext __user *) &frame->sctx;
-
-#if _NSIG != 64
-#error "Please adjust handle_signal()"
-#endif
- if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler)
- || __put_user(oldset->sig[0], &sc->oldmask)
-#ifdef CONFIG_PPC64
- || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
-#else
- || __put_user(oldset->sig[1], &sc->_unused[3])
-#endif
- || __put_user(to_user_ptr(&frame->mctx), &sc->regs)
- || __put_user(ksig->sig, &sc->signal))
- goto badframe;
-
- if (vdso32_sigtramp && tsk->mm->context.vdso_base) {
- sigret = 0;
- tramp = tsk->mm->context.vdso_base + vdso32_sigtramp;
- } else {
- sigret = __NR_sigreturn;
- tramp = (unsigned long) frame->mctx.tramp;
- }
-
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- tm_mctx = &frame->mctx_transact;
- if (MSR_TM_ACTIVE(msr)) {
- if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
- sigret, msr))
- goto badframe;
- }
- else
-#endif
- {
- if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1))
- goto badframe;
- }
-
- regs->link = tramp;
-
-#ifdef CONFIG_PPC_FPU_REGS
- tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
-#endif
-
- /* create a stack frame for the caller of the handler */
- newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
- if (put_user(regs->gpr[1], (u32 __user *)newsp))
- goto badframe;
-
- regs->gpr[1] = newsp;
- regs->gpr[3] = ksig->sig;
- regs->gpr[4] = (unsigned long) sc;
- regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler;
- /* enter the signal handler in big-endian mode */
- regs->msr &= ~MSR_LE;
- return 0;
-
-badframe:
- signal_fault(tsk, regs, "handle_signal32", frame);
-
- return 1;
-}
-
/*
* Do a signal return; undo the signal stack.
*/
--
2.25.0
^ permalink raw reply related
* [PATCH v2 12/25] powerpc/signal32: Simplify logging in handle_rt_signal32()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
If something is bad in the frame, there is no point in
knowing which part of the frame exactly is wrong as it
got allocated as a single block.
Always print the root address of the frame in case of
failed user access, just like handle_signal32().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal_32.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index deb729c8b79d..44a46911ff98 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -754,7 +754,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct rt_sigframe __user *rt_sf;
struct mcontext __user *frame;
struct mcontext __user *tm_frame = NULL;
- void __user *addr;
unsigned long newsp = 0;
int sigret;
unsigned long tramp;
@@ -767,7 +766,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
- addr = rt_sf;
if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
@@ -782,7 +780,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Save user registers on the stack */
frame = &rt_sf->uc.uc_mcontext;
- addr = frame;
if (vdso32_rt_sigtramp && tsk->mm->context.vdso_base) {
sigret = 0;
tramp = tsk->mm->context.vdso_base + vdso32_rt_sigtramp;
@@ -818,7 +815,6 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
- addr = (void __user *)regs->gpr[1];
if (put_user(regs->gpr[1], (u32 __user *)newsp))
goto badframe;
@@ -835,7 +831,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- signal_fault(tsk, regs, "handle_rt_signal32", addr);
+ signal_fault(tsk, regs, "handle_rt_signal32", rt_sf);
return 1;
}
--
2.25.0
^ permalink raw reply related
* [PATCH v2 11/25] powerpc/signal: Refactor bad frame logging
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
The logging of bad frame appears half a dozen of times
and is pretty similar.
Create signal_fault() fonction to perform that logging.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 11 +++++++++++
arch/powerpc/kernel/signal.h | 3 +++
arch/powerpc/kernel/signal_32.c | 35 +++++----------------------------
arch/powerpc/kernel/signal_64.c | 15 ++------------
4 files changed, 21 insertions(+), 43 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 5edded5c5d20..a1d31d26dbd6 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -355,3 +355,14 @@ static unsigned long get_tm_stackpointer(struct task_struct *tsk)
#endif
return ret;
}
+
+static const char fm32[] = KERN_INFO "%s[%d]: bad frame in %s: %p nip %08lx lr %08lx\n";
+static const char fm64[] = KERN_INFO "%s[%d]: bad frame in %s: %p nip %016lx lr %016lx\n";
+
+void signal_fault(struct task_struct *tsk, struct pt_regs *regs,
+ const char *where, void __user *ptr)
+{
+ if (show_unhandled_signals)
+ printk_ratelimited(regs->msr & MSR_64BIT ? fm64 : fm32, tsk->comm,
+ task_pid_nr(tsk), where, ptr, regs->nip, regs->link);
+}
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index fb98731348c3..f610cfafa478 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -93,4 +93,7 @@ static inline int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
#endif /* !defined(CONFIG_PPC64) */
+void signal_fault(struct task_struct *tsk, struct pt_regs *regs,
+ const char *where, void __user *ptr);
+
#endif /* _POWERPC_ARCH_SIGNAL_H */
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index e5b2801a94ac..deb729c8b79d 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -835,12 +835,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in handle_rt_signal32: "
- "%p nip %08lx lr %08lx\n",
- tsk->comm, tsk->pid,
- addr, regs->nip, regs->link);
+ signal_fault(tsk, regs, "handle_rt_signal32", addr);
return 1;
}
@@ -1092,12 +1087,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
return 0;
bad:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in sys_rt_sigreturn: "
- "%p nip %08lx lr %08lx\n",
- current->comm, current->pid,
- rt_sf, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_rt_sigreturn", rt_sf);
force_sig(SIGSEGV);
return 0;
@@ -1181,12 +1171,7 @@ SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
* We kill the task with a SIGSEGV in this situation.
*/
if (do_setcontext(ctx, regs, 1)) {
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO "%s[%d]: bad frame in "
- "sys_debug_setcontext: %p nip %08lx "
- "lr %08lx\n",
- current->comm, current->pid,
- ctx, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_debug_setcontext", ctx);
force_sig(SIGSEGV);
goto out;
@@ -1287,12 +1272,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in handle_signal32: "
- "%p nip %08lx lr %08lx\n",
- tsk->comm, tsk->pid,
- frame, regs->nip, regs->link);
+ signal_fault(tsk, regs, "handle_signal32", frame);
return 1;
}
@@ -1363,12 +1343,7 @@ SYSCALL_DEFINE0(sigreturn)
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(KERN_INFO
- "%s[%d]: bad frame in sys_sigreturn: "
- "%p nip %08lx lr %08lx\n",
- current->comm, current->pid,
- addr, regs->nip, regs->link);
+ signal_fault(current, regs, "sys_sigreturn", addr);
force_sig(SIGSEGV);
return 0;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index fec27d599e87..7df088b9ad0f 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -66,11 +66,6 @@ struct rt_sigframe {
char abigap[USER_REDZONE_SIZE];
} __attribute__ ((aligned (16)));
-static const char fmt32[] = KERN_INFO \
- "%s[%d]: bad frame in %s: %08lx nip %08lx lr %08lx\n";
-static const char fmt64[] = KERN_INFO \
- "%s[%d]: bad frame in %s: %016lx nip %016lx lr %016lx\n";
-
/*
* This computes a quad word aligned pointer inside the vmx_reserve array
* element. For historical reasons sigcontext might not be quad word aligned,
@@ -801,10 +796,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
- current->comm, current->pid, "rt_sigreturn",
- (long)uc, regs->nip, regs->link);
+ signal_fault(current, regs, "rt_sigreturn", uc);
force_sig(SIGSEGV);
return 0;
@@ -911,10 +903,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
return 0;
badframe:
- if (show_unhandled_signals)
- printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
- tsk->comm, tsk->pid, "setup_rt_frame",
- (long)frame, regs->nip, regs->link);
+ signal_fault(current, regs, "handle_rt_signal64", frame);
return 1;
}
--
2.25.0
^ permalink raw reply related
* [PATCH v2 10/25] powerpc/signal: Call get_tm_stackpointer() from get_sigframe()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
Instead of calling get_tm_stackpointer() from the caller, call it
directly from get_sigframe(). This avoids a double call and
allows get_tm_stackpointer() to become static and be inlined
into get_sigframe() by GCC.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 9 ++++++---
arch/powerpc/kernel/signal.h | 6 ++----
arch/powerpc/kernel/signal_32.c | 4 ++--
arch/powerpc/kernel/signal_64.c | 2 +-
4 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index a295d482adec..5edded5c5d20 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -144,10 +144,13 @@ int show_unhandled_signals = 1;
/*
* Allocate space for the signal frame
*/
-void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
- size_t frame_size, int is_32)
+static unsigned long get_tm_stackpointer(struct task_struct *tsk);
+
+void __user *get_sigframe(struct ksignal *ksig, struct task_struct *tsk,
+ size_t frame_size, int is_32)
{
unsigned long oldsp, newsp;
+ unsigned long sp = get_tm_stackpointer(tsk);
/* Default to using normal stack */
if (is_32)
@@ -304,7 +307,7 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
user_enter();
}
-unsigned long get_tm_stackpointer(struct task_struct *tsk)
+static unsigned long get_tm_stackpointer(struct task_struct *tsk)
{
/* When in an active transaction that takes a signal, we need to be
* careful with the stack. It's possible that the stack has moved back
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 6c2a33ab042c..fb98731348c3 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -10,8 +10,8 @@
#ifndef _POWERPC_ARCH_SIGNAL_H
#define _POWERPC_ARCH_SIGNAL_H
-extern void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
- size_t frame_size, int is_32);
+void __user *get_sigframe(struct ksignal *ksig, struct task_struct *tsk,
+ size_t frame_size, int is_32);
extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
@@ -19,8 +19,6 @@ extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
extern int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
-extern unsigned long get_tm_stackpointer(struct task_struct *tsk);
-
#ifdef CONFIG_VSX
extern unsigned long copy_vsx_to_user(void __user *to,
struct task_struct *task);
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 61621acacc63..e5b2801a94ac 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -766,7 +766,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
/* Put a Real Time Context onto stack */
- rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
+ rt_sf = get_sigframe(ksig, tsk, sizeof(*rt_sf), 1);
addr = rt_sf;
if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
@@ -1226,7 +1226,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
#endif
/* Set up Signal Frame */
- frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 1);
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index d3db78732070..fec27d599e87 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -822,7 +822,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
unsigned long msr = regs->msr;
#endif
- frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
+ frame = get_sigframe(ksig, tsk, sizeof(*frame), 0);
if (!access_ok(frame, sizeof(*frame)))
goto badframe;
--
2.25.0
^ permalink raw reply related
* [PATCH v2 05/25] powerpc/signal: Don't manage floating point regs when no FPU
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
There is no point in copying floating point regs when there
is no FPU and MATH_EMULATION is not selected.
Create a new CONFIG_PPC_FPU_REGS bool that is selected by
CONFIG_MATH_EMULATION and CONFIG_PPC_FPU, and use it to
opt out everything related to fp_state in thread_struct.
The asm const used only by fpu.S are opted out with CONFIG_PPC_FPU
as fpu.S build is conditionnal to CONFIG_PPC_FPU.
The following app spends approx 8.1 seconds system time on an 8xx
without the patch, and 7.0 seconds with the patch (13.5% reduction).
On an 832x, it spends approx 2.6 seconds system time without
the patch and 2.1 seconds with the patch (19% reduction).
void sigusr1(int sig) { }
int main(int argc, char **argv)
{
int i = 100000;
signal(SIGUSR1, sigusr1);
for (;i--;)
raise(SIGUSR1);
exit(0);
}
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/processor.h | 2 ++
arch/powerpc/kernel/asm-offsets.c | 2 ++
arch/powerpc/kernel/process.c | 4 ++++
arch/powerpc/kernel/ptrace/Makefile | 4 ++--
arch/powerpc/kernel/ptrace/ptrace-decl.h | 14 ++++++++++++++
arch/powerpc/kernel/ptrace/ptrace-view.c | 2 ++
arch/powerpc/kernel/signal.h | 14 +++++++++++++-
arch/powerpc/kernel/signal_32.c | 4 ++++
arch/powerpc/kernel/traps.c | 2 ++
arch/powerpc/platforms/Kconfig.cputype | 4 ++++
11 files changed, 50 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1f48bbfb3ce9..a2611880b904 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -416,6 +416,7 @@ config HUGETLB_PAGE_SIZE_VARIABLE
config MATH_EMULATION
bool "Math emulation"
depends on 4xx || PPC_8xx || PPC_MPC832x || BOOKE
+ select PPC_FPU_REGS
help
Some PowerPC chips designed for embedded applications do not have
a floating-point unit and therefore do not implement the
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ed0d633ab5aa..e20b0c5abe62 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -175,8 +175,10 @@ struct thread_struct {
#endif
/* Debug Registers */
struct debug_reg debug;
+#ifdef CONFIG_PPC_FPU_REGS
struct thread_fp_state fp_state;
struct thread_fp_state *fp_save_area;
+#endif
int fpexc_mode; /* floating-point exception mode */
unsigned int align_ctl; /* alignment handling control */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..6cb36c341c70 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -110,9 +110,11 @@ int main(void)
#ifdef CONFIG_BOOKE
OFFSET(THREAD_NORMSAVES, thread_struct, normsave[0]);
#endif
+#ifdef CONFIG_PPC_FPU
OFFSET(THREAD_FPEXC_MODE, thread_struct, fpexc_mode);
OFFSET(THREAD_FPSTATE, thread_struct, fp_state.fpr);
OFFSET(THREAD_FPSAVEAREA, thread_struct, fp_save_area);
+#endif
OFFSET(FPSTATE_FPSCR, thread_fp_state, fpscr);
OFFSET(THREAD_LOAD_FP, thread_struct, load_fp);
#ifdef CONFIG_ALTIVEC
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 016bd831908e..7e0082ac0a39 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1694,7 +1694,9 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
p->thread.ptrace_bps[i] = NULL;
#endif
+#ifdef CONFIG_PPC_FPU_REGS
p->thread.fp_save_area = NULL;
+#endif
#ifdef CONFIG_ALTIVEC
p->thread.vr_save_area = NULL;
#endif
@@ -1821,8 +1823,10 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
#endif
current->thread.load_slb = 0;
current->thread.load_fp = 0;
+#ifdef CONFIG_PPC_FPU_REGS
memset(¤t->thread.fp_state, 0, sizeof(current->thread.fp_state));
current->thread.fp_save_area = NULL;
+#endif
#ifdef CONFIG_ALTIVEC
memset(¤t->thread.vr_state, 0, sizeof(current->thread.vr_state));
current->thread.vr_state.vscr.u[3] = 0x00010000; /* Java mode disabled */
diff --git a/arch/powerpc/kernel/ptrace/Makefile b/arch/powerpc/kernel/ptrace/Makefile
index 77abd1a5a508..8ebc11d1168d 100644
--- a/arch/powerpc/kernel/ptrace/Makefile
+++ b/arch/powerpc/kernel/ptrace/Makefile
@@ -6,11 +6,11 @@
CFLAGS_ptrace-view.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
obj-y += ptrace.o ptrace-view.o
-obj-y += ptrace-fpu.o
+obj-$(CONFIG_PPC_FPU_REGS) += ptrace-fpu.o
obj-$(CONFIG_COMPAT) += ptrace32.o
obj-$(CONFIG_VSX) += ptrace-vsx.o
ifneq ($(CONFIG_VSX),y)
-obj-y += ptrace-novsx.o
+obj-$(CONFIG_PPC_FPU_REGS) += ptrace-novsx.o
endif
obj-$(CONFIG_ALTIVEC) += ptrace-altivec.o
obj-$(CONFIG_SPE) += ptrace-spe.o
diff --git a/arch/powerpc/kernel/ptrace/ptrace-decl.h b/arch/powerpc/kernel/ptrace/ptrace-decl.h
index eafe5f0f6289..3487f2c9735c 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-decl.h
+++ b/arch/powerpc/kernel/ptrace/ptrace-decl.h
@@ -165,8 +165,22 @@ int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data);
extern const struct user_regset_view user_ppc_native_view;
/* ptrace-fpu */
+#ifdef CONFIG_PPC_FPU_REGS
int ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data);
int ptrace_put_fpr(struct task_struct *child, int index, unsigned long data);
+#else
+static inline int
+ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data)
+{
+ return -EIO;
+}
+
+static inline int
+ptrace_put_fpr(struct task_struct *child, int index, unsigned long data)
+{
+ return -EIO;
+}
+#endif
/* ptrace-(no)adv */
void ppc_gethwdinfo(struct ppc_debug_info *dbginfo);
diff --git a/arch/powerpc/kernel/ptrace/ptrace-view.c b/arch/powerpc/kernel/ptrace/ptrace-view.c
index 7e6478e7ed07..f1df8c62baf1 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-view.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-view.c
@@ -520,11 +520,13 @@ static const struct user_regset native_regsets[] = {
.size = sizeof(long), .align = sizeof(long),
.regset_get = gpr_get, .set = gpr_set
},
+#ifdef CONFIG_PPC_FPU_REGS
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
.size = sizeof(double), .align = sizeof(double),
.regset_get = fpr_get, .set = fpr_set
},
+#endif
#ifdef CONFIG_ALTIVEC
[REGSET_VMX] = {
.core_note_type = NT_PPC_VMX, .n = 34,
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 4626d39cc0f0..6c2a33ab042c 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -34,7 +34,7 @@ unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
-#else
+#elif defined(CONFIG_PPC_FPU_REGS)
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
@@ -63,6 +63,18 @@ copy_ckfpr_from_user(struct task_struct *task, void __user *from)
ELF_NFPREG * sizeof(double));
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
+#else
+static inline unsigned long
+copy_fpr_to_user(void __user *to, struct task_struct *task)
+{
+ return 0;
+}
+
+static inline unsigned long
+copy_fpr_from_user(struct task_struct *task, void __user *from)
+{
+ return 0;
+}
#endif
#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 96950f189b5a..7b291707eb31 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -814,7 +814,9 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
}
regs->link = tramp;
+#ifdef CONFIG_PPC_FPU_REGS
tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
+#endif
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16);
@@ -1271,7 +1273,9 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
regs->link = tramp;
+#ifdef CONFIG_PPC_FPU_REGS
tsk->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */
+#endif
/* create a stack frame for the caller of the handler */
newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d1ebe152f210..5c68f0de905c 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1194,7 +1194,9 @@ static void parse_fpe(struct pt_regs *regs)
flush_fp_to_thread(current);
+#ifdef CONFIG_PPC_FPU_REGS
code = __parse_fpscr(current->thread.fp_state.fpscr);
+#endif
_exception(SIGFPE, regs, code, regs->nip);
}
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 87737ec86d39..40ffcdba42b8 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -225,9 +225,13 @@ config PPC_E500MC
such as e5500/e6500), and must be disabled for running on
e500v1 or e500v2.
+config PPC_FPU_REGS
+ bool
+
config PPC_FPU
bool
default y if PPC64
+ select PPC_FPU_REGS
config FSL_EMB_PERFMON
bool "Freescale Embedded Perfmon"
--
2.25.0
^ permalink raw reply related
* [PATCH v2 08/25] powerpc/signal: Move access_ok() out of get_sigframe()
From: Christophe Leroy @ 2020-08-18 17:19 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <cover.1597770847.git.christophe.leroy@csgroup.eu>
This access_ok() will soon be performed by user_access_begin().
So move it out of get_sigframe().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
arch/powerpc/kernel/signal.c | 4 ----
arch/powerpc/kernel/signal_32.c | 4 ++--
arch/powerpc/kernel/signal_64.c | 2 +-
3 files changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 3b56db02b762..1be5fd01f866 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -154,10 +154,6 @@ void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
oldsp = sigsp(oldsp, ksig);
newsp = (oldsp - frame_size) & ~0xFUL;
- /* Check access */
- if (!access_ok((void __user *)newsp, oldsp - newsp))
- return NULL;
-
return (void __user *)newsp;
}
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 8cbc9ac1343d..61621acacc63 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -768,7 +768,7 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Put a Real Time Context onto stack */
rt_sf = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*rt_sf), 1);
addr = rt_sf;
- if (unlikely(rt_sf == NULL))
+ if (!access_ok(rt_sf, sizeof(*rt_sf)))
goto badframe;
/* Put the siginfo & fill in most of the ucontext */
@@ -1227,7 +1227,7 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
/* Set up Signal Frame */
frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 1);
- if (unlikely(frame == NULL))
+ if (!access_ok(frame, sizeof(*frame)))
goto badframe;
sc = (struct sigcontext __user *) &frame->sctx;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index cae612bdde5f..d3db78732070 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -823,7 +823,7 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
#endif
frame = get_sigframe(ksig, get_tm_stackpointer(tsk), sizeof(*frame), 0);
- if (unlikely(frame == NULL))
+ if (!access_ok(frame, sizeof(*frame)))
goto badframe;
err |= __put_user(&frame->info, &frame->pinfo);
--
2.25.0
^ permalink raw reply related
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