Patch provides the ability for a process to
associate a pkey with a address range.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Finally this patch provides the ability for a process to
allocate and free a protection key.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PAPR defines 'ibm,processor-storage-keys' property. It exports two
values. The first value holds the number of data-access keys and the
second holds the number of instruction-access keys. Due to a bug in
the firmware, instruction-access keys is always reported as zero.
However any key can be configured to disable data-access and/or
disable execution-access. The inavailablity of the second value is not
a big handicap, though it could have been used to determine if the
platform supported disable-execution-access.
Non-PAPR platforms do not define this property in the device tree yet.
Fortunately power8 is the only released Non-PAPR platform that is
supported. Here, we hardcode the number of supported pkey to 32, by
consulting the PowerISA3.0
This patch calculates the number of keys supported by the platform.
Also it determines the platform support for read/write/execution
access support for pkeys.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Use a PVR check instead of CPU_FTR for execute. Restrict to
Power7/8/9 for now until older CPUs are tested.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The AMR/IAMR/UAMOR are part of the program context.
Allow it to be accessed via ptrace and through core files.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The value of the pkey, whose protection got violated,
is made available in si_pkey field of the siginfo structure.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
get_mm_addr_key() helper returns the pkey associated with
an address corresponding to a given mm_struct.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Handle Data and Instruction exceptions caused by memory
protection-key.
The CPU will detect the key fault if the HPTE is already
programmed with the key.
However if the HPTE is not hashed, a key fault will not
be detected by the hardware. The software will detect
pkey violation in such a case.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch provides the implementation for
arch_vma_access_permitted(). Returns true if the
requested access is allowed by pkey associated with the
vma.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Make sure that the kernel does not access user pages without
checking their key-protection.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Integrate with upstream version of pte_access_permitted()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
helper function that checks if the read/write/execute is allowed
on the pte.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Map the PTE protection key bits to the HPTE key protection bits,
while creating HPTE entries.
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Map the key protection bits of the vma to the pkey bits in
the PTE.
The PTE bits used for pkey are 3,4,5,6 and 57. The first
four bits are the same four bits that were freed up initially
in this patch series. remember? :-) Without those four bits
this patch wouldn't be possible.
BUT, on 4k kernel, bit 3, and 4 could not be freed up. remember?
Hence we have to be satisfied with 5, 6 and 7.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch independent code calls arch_override_mprotect_pkey()
to return a pkey that best matches the requested protection.
This patch provides the implementation.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch-independent code expects the arch to map
a pkey into the vma's protection bit setting.
The patch provides that ability.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch provides the implementation of execute-only pkey.
The architecture-independent layer expects the arch-dependent
layer, to support the ability to create and enable a special
key which has execute-only permission.
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Store and restore the AMR, IAMR and UAMOR register state of the task
before scheduling out and after scheduling in, respectively.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc has hardware support to disable execute on a pkey.
This patch enables the ability to create execute-disabled
keys.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch provides the detailed implementation for
a user to allocate a key and enable it in the hardware.
It provides the plumbing, but it cannot be used till
the system call is implemented. The next patch will
do so.
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cleanup the bits corresponding to a key in the AMR, and IAMR
register, when the key is newly allocated/activated or is freed.
We dont want some residual bits cause the hardware enforce
unintended behavior when the key is activated or freed.
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Introduce helper functions that can initialize the bits in the AMR,
IAMR and UAMOR register; the bits that correspond to the given pkey.
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Implements helper functions to read and write the key related
registers; AMR, IAMR, UAMOR.
AMR register tracks the read,write permission of a key
IAMR register tracks the execute permission of a key
UAMOR register enables and disables a key
Acked-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Total 32 keys are available on power7 and above. However
pkey 0,1 are reserved. So effectively we have 30 pkeys.
On 4K kernels, we do not have 5 bits in the PTE to
represent all the keys; we only have 3bits. Two of those
keys are reserved; pkey 0 and pkey 1. So effectively we
have 6 pkeys.
This patch keeps track of reserved keys, allocated keys
and keys that are currently free.
Also it adds skeletal functions and macros, that the
architecture-independent code expects to be available.
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Basic plumbing to initialize the pkey system.
Nothing is enabled yet. A later patch will enable it
once all the infrastructure is in place.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[mpe: Rework copyrights to use SPDX tags]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
GCC-4.4.4 raises errors when assigning a parameter in an anonymous
union, leading to this kind of failure:
drivers/mtd/nand/marvell_nand.c:1936:
warning: missing braces around initializer
warning: (near initialization for '(anonymous)[1].<anonymous>')
error: unknown field 'data' specified in initializer
error: unknown field 'addr' specified in initializer
Work around the situation by naming these unions.
Fixes: 8878b126df ("mtd: nand: add ->exec_op() implementation")
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Tested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
The function marvell_nfc_init_dma() allocates a DMA buffer without the
GFP_KERNEL modifier, that triggers this warning:
"marvell_nfc_init_dma() error: no modifiers for allocation."
Fix this by using (GFP_KERNEL | GFP_DMA) instead of only GFP_DMA as the
probe happens in non-interrupt context.
Fixes: 02f26ecf8c ("mtd: nand: add reworked Marvell NAND controller driver")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
When resetting iterator on a zero offset we need to discard any data
already in the buffer (count), and private state of the iterator (version).
For example this bug results in first line being repeated in /proc/mounts
if doing a zero size read before a non-zero size read.
Reported-by: Rich Felker <dalias@libc.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: e522751d60 ("seq_file: reset iterator to first record for zero offset")
Cc: <stable@vger.kernel.org> # v4.10
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Limiting the scan width to the known last bus via the command line can
accelerate the boot noteworthy.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jailhouse <jailhouse-dev@googlegroups.com>
Link: https://lkml.kernel.org/r/51f5fe62-ca8f-9286-5cdb-39df3fad78b4@siemens.com
Otherwise, Linux will not recognize precalibrated_tsc_khz and disable
the tsc as clocksource.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jailhouse <jailhouse-dev@googlegroups.com>
Link: https://lkml.kernel.org/r/975fbfc9-2a64-cc56-40d5-164992ec3916@siemens.com
The BPF verifier conflict was some minor contextual issue.
The TUN conflict was less trivial. Cong Wang fixed a memory leak of
tfile->tx_array in 'net'. This is an skb_array. But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
This series adds various misc improvements to BPF: detection
of BPF helper definition misconfiguration for mem/size argument
pairs, csum_diff helper also for XDP, various test cases,
removal of the recently added pure_initcall(), restriction
of the jit sysctls to cap_sys_admin for initns, a minor size
improvement for x86 jit in alu ops, output of complexity limit
to verifier log and last but not least having the event output
more flexible with moving to const_size_or_zero type.
Thanks!
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Similar rationale as in a60dd35d2e ("bpf: change bpf_perf_event_output
arg5 type to ARG_CONST_SIZE_OR_ZERO"), change the type to CONST_SIZE_OR_ZERO
such that we can better deal with optimized code. No changes needed in
bpf_event_output() as it can also deal with 0 size entirely (e.g. as only
wake-up signal with empty frame in perf RB, or packet dumps w/o meta data
as another such possibility).
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Given the limit could potentially get further adjustments in the
future, add it to the log so it becomes obvious what the current
limit is w/o having to check the source first. This may also be
helpful for debugging complexity related issues on kernels that
backport from upstream.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
For the BPF_REG_0 (BPF_REG_A in cBPF, respectively), we can use
the short form of the opcode as dst mapping is on eax/rax and
thus save a byte per such operation. Added to add/sub/and/or/xor
for 32/64 bit when K immediate is used. There may be more such
low-hanging fruit to add in future as well.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Given BPF reaches far beyond just networking these days, it was
never intended to allow setting and in some cases reading those
knobs out of a user namespace root running without CAP_SYS_ADMIN,
thus tighten such access.
Also the bpf_jit_enable = 2 debugging mode should only be allowed
if kptr_restrict is not set since it otherwise can leak addresses
to the kernel log. Dump a note to the kernel log that this is for
debugging JITs only when enabled.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Having a pure_initcall() callback just to permanently enable BPF
JITs under CONFIG_BPF_JIT_ALWAYS_ON is unnecessary and could leave
a small race window in future where JIT is still disabled on boot.
Since we know about the setting at compilation time anyway, just
initialize it properly there. Also consolidate all the individual
bpf_jit_enable variables into a single one and move them under one
location. Moreover, don't allow for setting unspecified garbage
values on them.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add couple of missing test cases for eBPF div/mod by zero to the
new test_verifier prog runtime feature. Also one for an empty prog
and only exit.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a couple of test cases for interpreter and JIT that are
related to an issue we faced some time ago in Cilium [1],
which is fixed in LLVM with commit e53750e1e086 ("bpf: fix
bug on silently truncating 64-bit immediate").
Test cases were run-time checking kernel to behave as intended
which should also provide some guidance for current or new
JITs in case they should trip over this. Added for cBPF and
eBPF.
[1] https://github.com/cilium/cilium/pull/2162
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Useful for porting cls_bpf programs w/o increasing program
complexity limits much at the same time, so add the helper
to XDP as well.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
I've seen two patch proposals now for helper additions that used
ARG_PTR_TO_MEM or similar in reg_X but no corresponding ARG_CONST_SIZE
in reg_X+1. Verifier won't complain in such case, but it will omit
verifying the memory passed to the helper thus ending up badly.
Detect such buggy helper function signature and bail out during
verification rather than finding them through review.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The xdp_redirect_cpu sample have some "builtin" monitoring of the
tracepoints for xdp_cpumap_*, but it is practical to have an external
tool that can monitor these transpoint as an easy way to troubleshoot
an application using XDP + cpumap.
Specifically I need such external tool when working on Suricata and
XDP cpumap redirect. Extend the xdp_monitor tool sample with
monitoring of these xdp_cpumap_* tracepoints. Model the output format
like xdp_redirect_cpu.
Given I needed to handle per CPU decoding for cpumap, this patch also
add per CPU info on the existing monitor events. This resembles part
of the builtin monitoring output from sample xdp_rxq_info. Thus, also
covering part of that sample in an external monitoring tool.
Performance wise, the cpumap tracepoints uses bulking, which cause
them to have very little overhead. Thus, they are enabled by default.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When a sector mode namespace is initially created, the arena's err_lock
is not initialized. If, on the other hand, the namespace already
exists, the mutex is initialized. To fix the issue, I moved the mutex
initialization into the arena_alloc, which is called by both
discover_arenas and create_arenas.
This was discovered on an older kernel where mutex_trylock checks the
count to determine whether the lock is held. Because the data structure
is kzalloc-d, that count was 0 (held), and I/O to the device would hang
forever waiting for the lock to be released (see btt_write_pg, for
example). Current kernels have a different mutex implementation that
checks for a non-null owner, and so this doesn't show up as a problem.
If that lock were ever contended, it might cause issues, but you'd have
to be really unlucky, I think.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If a dax buffer from a device that does not map pages is passed to
read(2) or write(2) as a target for direct-I/O it triggers SIGBUS. If
gdb attempts to examine the contents of a dax buffer from a device that
does not map pages it triggers SIGBUS. If fork(2) is called on a process
with a dax mapping from a device that does not map pages it triggers
SIGBUS. 'struct page' is required otherwise several kernel code paths
break in surprising ways. Disable filesystem-dax on devices that do not
map pages.
In addition to needing pfn_to_page() to be valid we also require devmap
pages. We need this to detect dax pages in the get_user_pages_fast()
path and so that we can stop managing the VM_MIXEDMAP flag. For DAX
drivers that have not supported get_user_pages() to date we allow them
to opt-in to supporting DAX with the CONFIG_FS_DAX_LIMITED configuration
option which requires ->direct_access() to return pfn_t_special() pfns.
This leaves DAX support in brd disabled and scheduled for removal.
Note that when the initial dax support was being merged a few years back
there was concern that struct page was unsuitable for use with next
generation persistent memory devices. The theoretical concern was that
struct page access, being such a hotly used data structure in the
kernel, would lead to media wear out. While that was a reasonable
conservative starting position it has not held true in practice. We have
long since committed to using devm_memremap_pages() to support higher
order kernel functionality that needs get_user_pages() and
pfn_to_page().
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Bring the ext2 filesystem in line with xfs that only warns and continues
when the "-o dax" option is specified to mount and the backing device
does not support dax. This is in preparation for removing dax support
from devices that do not enable get_user_pages() operations on dax
mappings. In other words 'gup' support is required and configurations
that were using so called 'page-less' dax will be converted back to
using the page cache.
Removing the broken 'page-less' dax support is a pre-requisite for
removing the "EXPERIMENTAL" warning when mounting a filesystem in dax
mode.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Bring the ext4 filesystem in line with xfs that only warns and continues
when the "-o dax" option is specified to mount and the backing device
does not support dax. This is in preparation for removing dax support
from devices that do not enable get_user_pages() operations on dax
mappings. In other words 'gup' support is required and configurations
that were using so called 'page-less' dax will be converted back to
using the page cache.
Removing the broken 'page-less' dax support is a pre-requisite for
removing the "EXPERIMENTAL" warning when mounting a filesystem in dax
mode.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In support of removing the VM_MIXEDMAP indication from DAX VMAs,
introduce pfn_t_special() for drivers to indicate that _PAGE_SPECIAL
should be used for DAX ptes. This also helps identify drivers like
dccssblk that only want to use DAX in a read-only fashion without
get_user_pages() support.
Ideally we could delete axonram and dcssblk DAX support, but if we need
to keep it better make it explicit that axonram and dcssblk only support
a sub-set of DAX due to missing _PAGE_DEVMAP support.
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
