commit e5f28623ce upstream.
In mce_threshold_create_device(), if threshold_create_bank() fails, the
previously allocated threshold banks array @bp will be leaked because
the call to mce_threshold_remove_device() will not free it.
This happens because mce_threshold_remove_device() fetches the pointer
through the threshold_banks per-CPU variable but bp is written there
only after the bank creation is successful, and not before, when
threshold_create_bank() fails.
Add a helper which unwinds all the bank creation work previously done
and pass into it the previously allocated threshold banks array for
freeing.
[ bp: Massage. ]
Fixes: 6458de97fc ("x86/mce/amd: Straighten CPU hotplug path")
Co-developed-by: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Signed-off-by: Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Co-developed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220329104705.65256-3-ammarfaizi2@gnuweeb.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e589f9b707 upstream.
All error handling paths lead to 'out' where many resources are freed.
Do it as well here instead of a direct return, otherwise 'log', 'ra' and
'log->one_page_buf' (at least) will leak.
Fixes: b46acd6a6a ("fs/ntfs3: Add NTFS journal")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3880f2b816 upstream.
Two problems:
1. ntfs3_setattr can't truncate preallocated space;
2. if allocated fragment "cross" valid size, then fragment splits into two parts:
- normal part;
- unwritten part (here we must return FIEMAP_EXTENT_LAST).
Before this commit we returned FIEMAP_EXTENT_LAST for whole fragment.
Fixes xfstest generic/092
Fixes: 4342306f0f ("fs/ntfs3: Add file operations and implementation")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a44623d927 upstream.
It has been observed with certain PCIe USB cards (like Inateck connected
to AM64 EVM or J7200 EVM) that as soon as the primary roothub is
registered, port status change is handled even before xHC is running
leading to cold plug USB devices not detected. For such cases, registering
both the root hubs along with the second HCD is required. Add support for
deferring roothub registration in usb_add_hcd(), so that both primary and
secondary roothubs are registered along with the second HCD.
This patch has been added and reverted earier as it triggered a race
in usb device enumeration.
That race is now fixed in 5.16-rc3, and in stable back to 5.4
commit 6cca13de26 ("usb: hub: Fix locking issues with address0_mutex")
commit 6ae6dc22d2 ("usb: hub: Fix usb enumeration issue due to address0
race")
CC: stable@vger.kernel.org # 5.4+
Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Tested-by: Chris Chiu <chris.chiu@canonical.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Link: https://lore.kernel.org/r/20220510091630.16564-2-kishon@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3c5880745b upstream.
When dwc3_gadget_ep_cleanup_completed_requests() called to
dwc3_gadget_giveback() where the dwc3 lock is released, other thread is
able to execute. In this situation, usb_ep_disable() gets the chance to
clear endpoint descriptor pointer which leds to the null pointer
dereference problem. So needs to move the null pointer check to a proper
place.
Example call stack:
Thread#1:
dwc3_thread_interrupt()
spin_lock
-> dwc3_process_event_buf()
-> dwc3_process_event_entry()
-> dwc3_endpoint_interrupt()
-> dwc3_gadget_endpoint_trbs_complete()
-> dwc3_gadget_ep_cleanup_completed_requests()
...
-> dwc3_giveback()
spin_unlock
Thread#2 executes
Thread#2:
configfs_composite_disconnect()
-> __composite_disconnect()
-> ffs_func_disable()
-> ffs_func_set_alt()
-> ffs_func_eps_disable()
-> usb_ep_disable()
wait for dwc3 spin_lock
Thread#1 released lock
clear endpoint.desc
Fixes: 2628844812 ("usb: dwc3: gadget: Fix null pointer exception")
Cc: stable <stable@kernel.org>
Signed-off-by: Albert Wang <albertccwang@google.com>
Link: https://lore.kernel.org/r/20220518061315.3359198-1-albertccwang@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 26ae2c942b upstream.
Running the driver through kasan gives an interesting splat:
BUG: KASAN: global-out-of-bounds in isp1760_register+0x180/0x70c
Read of size 20 at addr f1db2e64 by task swapper/0/1
(...)
isp1760_register from isp1760_plat_probe+0x1d8/0x220
(...)
This happens because the loop reading the regmap fields for the
different ISP1760 variants look like this:
for (i = 0; i < HC_FIELD_MAX; i++) { ... }
Meaning it expects the arrays to be at least HC_FIELD_MAX - 1 long.
However the arrays isp1760_hc_reg_fields[], isp1763_hc_reg_fields[],
isp1763_hc_volatile_ranges[] and isp1763_dc_volatile_ranges[] are
dynamically sized during compilation.
Fix this by putting an empty assignment to the [HC_FIELD_MAX]
and [DC_FIELD_MAX] array member at the end of each array.
This will make the array one member longer than it needs to be,
but avoids the risk of overwriting whatever is inside
[HC_FIELD_MAX - 1] and is simple and intuitive to read. Also
add comments explaining what is going on.
Fixes: 1da9e1c068 ("usb: isp1760: move to regmap for register access")
Cc: stable@vger.kernel.org
Cc: Rui Miguel Silva <rui.silva@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Rui Miguel Silva <rui.silva@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220516091424.391209-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9bfa7b3634 upstream.
Set microphone pins 0x18 (rear) and 0x19 (front) to VREF_50 to fix the
microphone noise on ASUS TUF B550M-PLUS which uses the ALCS1200A codec.
The initial value was VREF_80.
The same issue is also present on Windows using both the default Windows
driver and all tested Realtek drivers before version 6.0.9049.1. Comparing
Realtek driver 6.0.9049.1 (the first one without the microphone noise) to
Realtek driver 6.0.9047.1 (the last one with the microphone noise)
revealed that the fix is the result of setting pins 0x18 and 0x19 to
VREF_50.
This fix may also work for other boards that have been reported to have
the same microphone issue and use the ALC1150 and ALCS1200A codecs, since
these codecs are similar and the fix in the Realtek driver on Windows is
common for both. However, it is currently enabled only for ASUS TUF
B550M-PLUS as this is the only board that could be tested.
Signed-off-by: Marios Levogiannis <marios.levogiannis@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220530074131.12258-1-marios.levogiannis@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 61114e734c upstream.
After commit 49b290e430 ("riscv: prevent compressed instructions in
alternatives"), builds with LLVM's integrated assembler fail:
In file included from arch/riscv/mm/init.c:10:
In file included from ./include/linux/mm.h:29:
In file included from ./include/linux/pgtable.h:6:
In file included from ./arch/riscv/include/asm/pgtable.h:108:
./arch/riscv/include/asm/tlbflush.h:23:2: error: expected assembly-time absolute expression
ALT_FLUSH_TLB_PAGE(__asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory"));
^
./arch/riscv/include/asm/errata_list.h:33:5: note: expanded from macro 'ALT_FLUSH_TLB_PAGE'
asm(ALTERNATIVE("sfence.vma %0", "sfence.vma", SIFIVE_VENDOR_ID, \
^
./arch/riscv/include/asm/alternative-macros.h:187:2: note: expanded from macro 'ALTERNATIVE'
_ALTERNATIVE_CFG(old_content, new_content, vendor_id, errata_id, CONFIG_k)
^
./arch/riscv/include/asm/alternative-macros.h:113:2: note: expanded from macro '_ALTERNATIVE_CFG'
__ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k))
^
./arch/riscv/include/asm/alternative-macros.h:110:2: note: expanded from macro '__ALTERNATIVE_CFG'
ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c)
^
./arch/riscv/include/asm/alternative-macros.h:99:3: note: expanded from macro 'ALT_NEW_CONTENT'
".org . - (889b - 888b) + (887b - 886b)\n" \
^
<inline asm>:26:6: note: instantiated into assembly here
.org . - (889b - 888b) + (887b - 886b)
^
This error happens because LLVM's integrated assembler has a one-pass
design, which means it cannot figure out the instruction lengths when
the .org directive is outside of the subsection that contains the
instructions, which was changed by the .option directives added by the
above change.
Move the .org directives before the .previous directive so that these
directives are always within the same subsection, which resolves the
failures and does not introduce any new issues with GNU as. This was
done for arm64 in commit 966a0acce2 ("arm64/alternatives: move length
validation inside the subsection") and commit 22315a2296 ("arm64:
alternatives: Move length validation in alternative_{insn, endif}").
While there is no error from the assembly versions of the macro, they
appear to have the same problem so just make the same change there as
well so that there are no problems in the future.
Link: https://github.com/ClangBuiltLinux/linux/issues/1640
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20220516214520.3252074-1-nathan@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 35d33c76d6 upstream.
Because of the stack canary feature that reads from the current task
structure the stack canary value, the thread pointer register "tp" must
be set before calling any C function from head.S: by chance, setup_vm
and all the functions that it calls does not seem to be part of the
functions where the canary check is done, but in the following commits,
some functions will.
Fixes: f2c9699f65 ("riscv: Add STACKPROTECTOR supported")
Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b046f98481 upstream.
Keep the pa_path (hardware path) of the graphics card in sti_struct and use
this info to give more useful info which card is currently being used.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cf936af790 upstream.
Implement fb_is_primary_device() function, so that fbcon detects if this
framebuffer belongs to the default graphics card which was used to start
the system.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6045ab5fea upstream.
bFLT binaries are usually created using elf2flt.
The linker script used by elf2flt has defined the .data section like the
following for the last 19 years:
.data : {
_sdata = . ;
__data_start = . ;
data_start = . ;
*(.got.plt)
*(.got)
FILL(0) ;
. = ALIGN(0x20) ;
LONG(-1)
. = ALIGN(0x20) ;
...
}
It places the .got.plt input section before the .got input section.
The same is true for the default linker script (ld --verbose) on most
architectures except x86/x86-64.
The binfmt_flat loader should relocate all GOT entries until it encounters
a -1 (the LONG(-1) in the linker script).
The problem is that the .got.plt input section starts with a GOTPLT header
(which has size 16 bytes on elf64-riscv and 8 bytes on elf32-riscv), where
the first word is set to -1. See the binutils implementation for riscv [1].
This causes the binfmt_flat loader to stop relocating GOT entries
prematurely and thus causes the application to crash when running.
Fix this by skipping the whole GOTPLT header, since the whole GOTPLT header
is reserved for the dynamic linker.
The GOTPLT header will only be skipped for bFLT binaries with flag
FLAT_FLAG_GOTPIC set. This flag is unconditionally set by elf2flt if the
supplied ELF binary has the symbol _GLOBAL_OFFSET_TABLE_ defined.
ELF binaries without a .got input section should thus remain unaffected.
Tested on RISC-V Canaan Kendryte K210 and RISC-V QEMU nommu_virt_defconfig.
[1] https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=bfd/elfnn-riscv.c;hb=binutils-2_38#l3275
Cc: <stable@vger.kernel.org>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220414091018.896737-1-niklas.cassel@wdc.com
Fixed-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202204182333.OIUOotK8-lkp@intel.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3753fcc229 upstream.
Maris found out that the quirk for TEAC devices to work around the
clock setup is needed to apply only when the base clock is changed,
e.g. from 48000-based clocks (48000, 96000, 192000, 384000) to
44100-based clocks (44100, 88200, 176400, 352800), or vice versa,
while switching to another clock with the same base clock doesn't need
the (forcible) interface setup.
This patch implements the optimization for the TEAC clock quirk to
avoid the unnecessary interface re-setup.
Fixes: 5ce0b06ae5 ("ALSA: usb-audio: Workaround for clock setup on TEAC devices")
Reported-by: Maris Abele <maris7abele@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220531130749.30357-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 97e6d7dab1 upstream.
The commit being fixed was aiming to disallow users from incorrectly
obtaining writable pointer to memory that is only meant to be read. This
is enforced now using a MEM_RDONLY flag.
For instance, in case of global percpu variables, when the BTF type is
not struct (e.g. bpf_prog_active), the verifier marks register type as
PTR_TO_MEM | MEM_RDONLY from bpf_this_cpu_ptr or bpf_per_cpu_ptr
helpers. However, when passing such pointer to kfunc, global funcs, or
BPF helpers, in check_helper_mem_access, there is no expectation
MEM_RDONLY flag will be set, hence it is checked as pointer to writable
memory. Later, verifier sets up argument type of global func as
PTR_TO_MEM | PTR_MAYBE_NULL, so user can use a global func to get around
the limitations imposed by this flag.
This check will also cover global non-percpu variables that may be
introduced in kernel BTF in future.
Also, we update the log message for PTR_TO_BUF case to be similar to
PTR_TO_MEM case, so that the reason for error is clear to user.
Fixes: 34d3a78c68 ("bpf: Make per_cpu_ptr return rdonly PTR_TO_MEM.")
Reviewed-by: Hao Luo <haoluo@google.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220319080827.73251-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b45043192b upstream.
The 'n_buckets * (value_size + sizeof(struct stack_map_bucket))' part of the
allocated memory for 'smap' is never used after the memlock accounting was
removed, thus get rid of it.
[ Note, Daniel:
Commit b936ca643a ("bpf: rework memlock-based memory accounting for maps")
moved `cost += n_buckets * (value_size + sizeof(struct stack_map_bucket))`
up and therefore before the bpf_map_area_alloc() allocation, sigh. In a later
step commit c85d69135a ("bpf: move memory size checks to bpf_map_charge_init()"),
and the overflow checks of `cost >= U32_MAX - PAGE_SIZE` moved into
bpf_map_charge_init(). And then 370868107b ("bpf: Eliminate rlimit-based
memory accounting for stackmap maps") finally removed the bpf_map_charge_init().
Anyway, the original code did the allocation same way as /after/ this fix. ]
Fixes: b936ca643a ("bpf: rework memlock-based memory accounting for maps")
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220407130423.798386-1-ytcoode@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a2aa95b71c upstream.
The cnt value in the 'cnt >= BPF_MAX_TRAMP_PROGS' check does not
include BPF_TRAMP_MODIFY_RETURN bpf programs, so the number of
the attached BPF_TRAMP_MODIFY_RETURN bpf programs in a trampoline
can exceed BPF_MAX_TRAMP_PROGS.
When this happens, the assignment '*progs++ = aux->prog' in
bpf_trampoline_get_progs() will cause progs array overflow as the
progs field in the bpf_tramp_progs struct can only hold at most
BPF_MAX_TRAMP_PROGS bpf programs.
Fixes: 88fd9e5352 ("bpf: Refactor trampoline update code")
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Link: https://lore.kernel.org/r/20220430130803.210624-1-ytcoode@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce3c4ad7f4 upstream.
nfsd4_release_lockowner() holds clp->cl_lock when it calls
check_for_locks(). However, check_for_locks() calls nfsd_file_get()
/ nfsd_file_put() to access the backing inode's flc_posix list, and
nfsd_file_put() can sleep if the inode was recently removed.
Let's instead rely on the stateowner's reference count to gate
whether the release is permitted. This should be a reliable
indication of locks-in-use since file lock operations and
->lm_get_owner take appropriate references, which are released
appropriately when file locks are removed.
Reported-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6d5aa418b3 upstream.
The reference to `explicit_in_reply_to` is pointless as when the
reference was added in the form of "#15" [1], Section 15) was "The
canonical patch format".
The reference of "#15" had not been properly updated in a couple of
reorganizations during the plain-text SubmittingPatches era.
Fix it by using `the_canonical_patch_format`.
[1]: 2ae19acaa5 ("Documentation: Add "how to write a good patch summary" to SubmittingPatches")
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Fixes: 5903019b2a ("Documentation/SubmittingPatches: convert it to ReST markup")
Fixes: 9b2c76777a ("Documentation/SubmittingPatches: enrich the Sphinx output")
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: stable@vger.kernel.org # v4.9+
Link: https://lore.kernel.org/r/64e105a5-50be-23f2-6cae-903a2ea98e18@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e57b2523bd upstream.
Under certain conditions uninitialized memory will be accessed.
As described by TCG Trusted Platform Module Library Specification,
rev. 1.59 (Part 3: Commands), if a TPM2_GetCapability is received,
requesting a capability, the TPM in field upgrade mode may return a
zero length list.
Check the property count in tpm2_get_tpm_pt().
Fixes: 2ab3241161 ("tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@infineon.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bb25f071fc upstream.
The imx412/imx577 sensor has a reset line that is active low not active
high. Currently the logic for this is inverted.
The right way to define the reset line is to declare it active low in the
DTS and invert the logic currently contained in the driver.
The DTS should represent the hardware does i.e. reset is active low.
So:
+ reset-gpios = <&tlmm 78 GPIO_ACTIVE_LOW>;
not:
- reset-gpios = <&tlmm 78 GPIO_ACTIVE_HIGH>;
I was a bit reticent about changing this logic since I thought it might
negatively impact @intel.com users. Googling a bit though I believe this
sensor is used on "Keem Bay" which is clearly a DTS based system and is not
upstream yet.
Fixes: 9214e86c0c ("media: i2c: Add imx412 camera sensor driver")
Cc: stable@vger.kernel.org
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e3a3bbe3e9 upstream.
A PCMD (Paging Crypto MetaData) page contains the PCMD
structures of enclave pages that have been encrypted and
moved to the shmem backing store. When all enclave pages
sharing a PCMD page are loaded in the enclave, there is no
need for the PCMD page and it can be truncated from the
backing store.
A few issues appeared around the truncation of PCMD pages. The
known issues have been addressed but the PCMD handling code could
be made more robust by loudly complaining if any new issue appears
in this area.
Add a check that will complain with a warning if the PCMD page is not
actually empty after it has been truncated. There should never be data
in the PCMD page at this point since it is was just checked to be empty
and truncated with enclave mutex held and is updated with the
enclave mutex held.
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Haitao Huang <haitao.huang@intel.com>
Link: https://lkml.kernel.org/r/6495120fed43fafc1496d09dd23df922b9a32709.1652389823.git.reinette.chatre@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit af117837ce upstream.
Haitao reported encountering a WARN triggered by the ENCLS[ELDU]
instruction faulting with a #GP.
The WARN is encountered when the reclaimer evicts a range of
pages from the enclave when the same pages are faulted back right away.
Consider two enclave pages (ENCLAVE_A and ENCLAVE_B)
sharing a PCMD page (PCMD_AB). ENCLAVE_A is in the
enclave memory and ENCLAVE_B is in the backing store. PCMD_AB contains
just one entry, that of ENCLAVE_B.
Scenario proceeds where ENCLAVE_A is being evicted from the enclave
while ENCLAVE_B is faulted in.
sgx_reclaim_pages() {
...
/*
* Reclaim ENCLAVE_A
*/
mutex_lock(&encl->lock);
/*
* Get a reference to ENCLAVE_A's
* shmem page where enclave page
* encrypted data will be stored
* as well as a reference to the
* enclave page's PCMD data page,
* PCMD_AB.
* Release mutex before writing
* any data to the shmem pages.
*/
sgx_encl_get_backing(...);
encl_page->desc |= SGX_ENCL_PAGE_BEING_RECLAIMED;
mutex_unlock(&encl->lock);
/*
* Fault ENCLAVE_B
*/
sgx_vma_fault() {
mutex_lock(&encl->lock);
/*
* Get reference to
* ENCLAVE_B's shmem page
* as well as PCMD_AB.
*/
sgx_encl_get_backing(...)
/*
* Load page back into
* enclave via ELDU.
*/
/*
* Release reference to
* ENCLAVE_B' shmem page and
* PCMD_AB.
*/
sgx_encl_put_backing(...);
/*
* PCMD_AB is found empty so
* it and ENCLAVE_B's shmem page
* are truncated.
*/
/* Truncate ENCLAVE_B backing page */
sgx_encl_truncate_backing_page();
/* Truncate PCMD_AB */
sgx_encl_truncate_backing_page();
mutex_unlock(&encl->lock);
...
}
mutex_lock(&encl->lock);
encl_page->desc &=
~SGX_ENCL_PAGE_BEING_RECLAIMED;
/*
* Write encrypted contents of
* ENCLAVE_A to ENCLAVE_A shmem
* page and its PCMD data to
* PCMD_AB.
*/
sgx_encl_put_backing(...)
/*
* Reference to PCMD_AB is
* dropped and it is truncated.
* ENCLAVE_A's PCMD data is lost.
*/
mutex_unlock(&encl->lock);
}
What happens next depends on whether it is ENCLAVE_A being faulted
in or ENCLAVE_B being evicted - but both end up with ENCLS[ELDU] faulting
with a #GP.
If ENCLAVE_A is faulted then at the time sgx_encl_get_backing() is called
a new PCMD page is allocated and providing the empty PCMD data for
ENCLAVE_A would cause ENCLS[ELDU] to #GP
If ENCLAVE_B is evicted first then a new PCMD_AB would be allocated by the
reclaimer but later when ENCLAVE_A is faulted the ENCLS[ELDU] instruction
would #GP during its checks of the PCMD value and the WARN would be
encountered.
Noting that the reclaimer sets SGX_ENCL_PAGE_BEING_RECLAIMED at the time
it obtains a reference to the backing store pages of an enclave page it
is in the process of reclaiming, fix the race by only truncating the PCMD
page after ensuring that no page sharing the PCMD page is in the process
of being reclaimed.
Cc: stable@vger.kernel.org
Fixes: 08999b2489 ("x86/sgx: Free backing memory after faulting the enclave page")
Reported-by: Haitao Huang <haitao.huang@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Haitao Huang <haitao.huang@intel.com>
Link: https://lkml.kernel.org/r/ed20a5db516aa813873268e125680041ae11dfcf.1652389823.git.reinette.chatre@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0e4e729a83 upstream.
Haitao reported encountering a WARN triggered by the ENCLS[ELDU]
instruction faulting with a #GP.
The WARN is encountered when the reclaimer evicts a range of
pages from the enclave when the same pages are faulted back
right away.
The SGX backing storage is accessed on two paths: when there
are insufficient free pages in the EPC the reclaimer works
to move enclave pages to the backing storage and as enclaves
access pages that have been moved to the backing storage
they are retrieved from there as part of page fault handling.
An oversubscribed SGX system will often run the reclaimer and
page fault handler concurrently and needs to ensure that the
backing store is accessed safely between the reclaimer and
the page fault handler. This is not the case because the
reclaimer accesses the backing store without the enclave mutex
while the page fault handler accesses the backing store with
the enclave mutex.
Consider the scenario where a page is faulted while a page sharing
a PCMD page with the faulted page is being reclaimed. The
consequence is a race between the reclaimer and page fault
handler, the reclaimer attempting to access a PCMD at the
same time it is truncated by the page fault handler. This
could result in lost PCMD data. Data may still be
lost if the reclaimer wins the race, this is addressed in
the following patch.
The reclaimer accesses pages from the backing storage without
holding the enclave mutex and runs the risk of concurrently
accessing the backing storage with the page fault handler that
does access the backing storage with the enclave mutex held.
In the scenario below a PCMD page is truncated from the backing
store after all its pages have been loaded in to the enclave
at the same time the PCMD page is loaded from the backing store
when one of its pages are reclaimed:
sgx_reclaim_pages() { sgx_vma_fault() {
...
mutex_lock(&encl->lock);
...
__sgx_encl_eldu() {
...
if (pcmd_page_empty) {
/*
* EPC page being reclaimed /*
* shares a PCMD page with an * PCMD page truncated
* enclave page that is being * while requested from
* faulted in. * reclaimer.
*/ */
sgx_encl_get_backing() <----------> sgx_encl_truncate_backing_page()
}
mutex_unlock(&encl->lock);
} }
In this scenario there is a race between the reclaimer and the page fault
handler when the reclaimer attempts to get access to the same PCMD page
that is being truncated. This could result in the reclaimer writing to
the PCMD page that is then truncated, causing the PCMD data to be lost,
or in a new PCMD page being allocated. The lost PCMD data may still occur
after protecting the backing store access with the mutex - this is fixed
in the next patch. By ensuring the backing store is accessed with the mutex
held the enclave page state can be made accurate with the
SGX_ENCL_PAGE_BEING_RECLAIMED flag accurately reflecting that a page
is in the process of being reclaimed.
Consistently protect the reclaimer's backing store access with the
enclave's mutex to ensure that it can safely run concurrently with the
page fault handler.
Cc: stable@vger.kernel.org
Fixes: 1728ab54b4 ("x86/sgx: Add a page reclaimer")
Reported-by: Haitao Huang <haitao.huang@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Haitao Huang <haitao.huang@intel.com>
Link: https://lkml.kernel.org/r/fa2e04c561a8555bfe1f4e7adc37d60efc77387b.1652389823.git.reinette.chatre@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>