Depending on whether the kernel is compiled with frame-pointer or not,
the temporary memory location used for the bp parameter in these macros
is referenced relative to the stack pointer or the frame pointer.
Hence we can never reference that parameter when we've modified either
the stack pointer or the frame pointer, because then the compiler would
generate an incorrect stack reference.
Fix this by pushing the temporary memory parameter on a known location on
the stack before modifying the stack- and frame pointers.
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
The reuseport_bpf_numa test case fails there's no numa support. The
test shouldn't fail if there's no support it should be skipped.
Fixes: 3c2c3c16aa ("reuseport, bpf: add test case for bpf_get_numa_node_id")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Only CPUs which speculate can speculate. Therefore, it seems prudent
to test for cpu_no_speculation first and only then determine whether
a specific speculating CPU is susceptible to store bypass speculation.
This is underlined by all CPUs currently listed in cpu_no_speculation
were present in cpu_no_spec_store_bypass as well.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Cc: konrad.wilk@oracle.com
Link: https://lkml.kernel.org/r/20180522090539.GA24668@light.dominikbrodowski.net
The X86_FEATURE_SSBD is an synthetic CPU feature - that is
it bit location has no relevance to the real CPUID 0x7.EBX[31]
bit position. For that we need the new CPU feature name.
Fixes: 52817587e7 ("x86/cpufeatures: Disentangle SSBD enumeration")
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: stable@vger.kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lkml.kernel.org/r/20180521215449.26423-2-konrad.wilk@oracle.com
Commit 001dde9400 ("mfd: cros ec: spi: Fix "in progress" error
signaling") pointed out some bad code, but its analysis and conclusion
was not 100% correct.
It *is* correct that we should not propagate result==EC_RES_IN_PROGRESS
for transport errors, because this has a special meaning -- that we
should follow up with EC_CMD_GET_COMMS_STATUS until the EC is no longer
busy. This is definitely the wrong thing for many commands, because
among other problems, EC_CMD_GET_COMMS_STATUS doesn't actually retrieve
any RX data from the EC, so commands that expected some data back will
instead start processing junk.
For such commands, the right answer is to either propagate the error
(and return that error to the caller) or resend the original command
(*not* EC_CMD_GET_COMMS_STATUS).
Unfortunately, commit 001dde9400 forgets a crucial point: that for
some long-running operations, the EC physically cannot respond to
commands any more. For example, with EC_CMD_FLASH_ERASE, the EC may be
re-flashing its own code regions, so it can't respond to SPI interrupts.
Instead, the EC prepares us ahead of time for being busy for a "long"
time, and fills its hardware buffer with EC_SPI_PAST_END. Thus, we
expect to see several "transport" errors (or, messages filled with
EC_SPI_PAST_END). So we should really translate that to a retryable
error (-EAGAIN) and continue sending EC_CMD_GET_COMMS_STATUS until we
get a ready status.
IOW, it is actually important to treat some of these "junk" values as
retryable errors.
Together with commit 001dde9400, this resolves bugs like the
following:
1. EC_CMD_FLASH_ERASE now works again (with commit 001dde9400, we
would abort the first time we saw EC_SPI_PAST_END)
2. Before commit 001dde9400, transport errors (e.g.,
EC_SPI_RX_BAD_DATA) seen in other commands (e.g.,
EC_CMD_RTC_GET_VALUE) used to yield junk data in the RX buffer; they
will now yield -EAGAIN return values, and tools like 'hwclock' will
simply fail instead of retrieving and re-programming undefined time
values
Fixes: 001dde9400 ("mfd: cros ec: spi: Fix "in progress" error signaling")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Getting a compiler warning, Wstringop-overflow, in
arch/nds32/kernel/vdso.c when kernel is built by gcc-8. Declaring
vdso_start and vdso_end as a pointer to fix this compiler warning.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
In order to ensure that all data in source page has been written back
to memory before copy_page, the local irq shall be disabled before
calling cpu_dcache_wb_page(). In addition, removing unneeded page
invalidation for 'to' page.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
According to Documentation/cachetlb.txt, the cache of the page at vmaddr
shall be flushed in flush_anon_page instead of the cache of the page at
page_address(page).
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
1. Disable local irq before d-cache write-back and invalidate.
The cpu_dcache_wbinval_page function is composed of d-cache
write-back and invalidate. If the local irq is enabled when calling
cpu_dcache_wbinval_page, the content of d-cache is possibly updated
between write-back and invalidate. In this case, the updated data will
be dropped due to the following d-cache invalidation. Therefore, we
disable the local irq before calling cpu_dcache_wbinval_page.
2. Correct the data write-back for page aliasing case.
Only the page whose (page->index << PAGE_SHIFT) is located at the
same page color as page_address(page) needs to execute data write-back
in flush_dcache_page function.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
If the kernel config 'CONFIG_ALIGNMENT_TRAP' and the file
'/proc/sys/nds32/unaligned_access/enable' are set, the kernel
unaligned access handler does not handle correctly when the
value of immediate field is negative. This commit fixes the
unaligned access handler in kernel.
Signed-off-by: Nickhu <nickhu@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Change the name of the file '/proc/sys/nds32/unaligned_acess'
to '/proc/sys/nds32/unaligned_access'
Signed-off-by: Nickhu <nickhu@andestech.com>
Reviewed-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
The nds32 architecture will use physical memory when interrupt or
exception comes and it will use the setting of NTC0-4. The original
implementation didn't consider the DRAM start address may start from 1GB,
2GB or 3GB to cause this issue. It will write the data to DRAM if it is
running in physical address however kernel will read the data with
virtaul address through data cache. In this case, the data of DRAM is
latest.
This fix will set the correct cacheability to let kernel write/read the
latest data in cache instead of DRAM.
Signed-off-by: Greentime Hu <greentime@andestech.com>
We use tlbop to map virtual address in the first beginning, however it
may map too much if DRAM size is not that big. We have to invalidate the
mapping when the page table is created.
Signed-off-by: Greentime Hu <greentime@andestech.com>
This way we can build kernel with CONFIG_CPU_LITTLE_ENDIAN=y. Build allmodconfig
and allnoconfig are available too. It also fixes the endian mismatch issue
because AFLAGS and LDFLAGS is not passed correctly.
Signed-off-by: Vincent Ren-Wei Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
It broke the 'allmodconfig' build when CONFIG_TRACE_IRQFLAGS is enabled.
Signed-off-by: Nick Chun-Ming Hu <nickhu@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
It broke the 'allmodconfig' build.
We need to include <linux/types.h> to make sure the type is defined
before using it.
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
It broke the 'allmodconfig' build.
fs/xfs/xfs_buf.c: In function 'xfs_buf_bio_end_io':
fs/xfs/xfs_buf.c:1242:3: error: implicit declaration of function 'invalidate_kernel_vmap_range' [-Werror=implicit-function-declaration]
invalidate_kernel_vmap_range(bp->b_addr, xfs_buf_vmap_len(bp));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/xfs/xfs_buf.c: In function 'xfs_buf_ioapply_map':
fs/xfs/xfs_buf.c:1312:4: error: implicit declaration of function 'flush_kernel_vmap_range' [-Werror=implicit-function-declaration]
flush_kernel_vmap_range(bp->b_addr,
^~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
It broke the 'allmodconfig' build.
drivers/gpu/drm/udl/udl_fb.c: In function 'udl_fb_mmap':
drivers/gpu/drm/udl/udl_fb.c:183:52: error: 'PAGE_SHARED' undeclared (first use in this function)
if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))
^~~~~~~~~~~
drivers/gpu/drm/udl/udl_fb.c:183:52: note: each undeclared identifier is reported only once for each function it appears in
make[4]: *** [drivers/gpu/drm/udl/udl_fb.o] Error 1
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
When I compiled with allmodconfig, it caused this building failed.
crypto/xor.c:25:21: fatal error: asm/xor.h: No such file or directory
#include <asm/xor.h>
^
compilation terminated.
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
To include kernel/Kconfig.freezer to make sure the dependency between
CONFIG_CGROUP_FREEZER and CONFIG_FREEZER
It will cause building error when I make allmodconfig.
kernel/cgroup/freezer.c: In function 'freezer_css_online':
kernel/cgroup/freezer.c:116:15: error: 'system_freezing_cnt' undeclared (first use in this function)
atomic_inc(&system_freezing_cnt);
^~~~~~~~~~~~~~~~~~~
kernel/cgroup/freezer.c:116:15: note: each undeclared identifier is reported only once for each function it appears in
kernel/cgroup/freezer.c: In function 'freezer_css_offline':
kernel/cgroup/freezer.c:137:15: error: 'system_freezing_cnt' undeclared (first use in this function)
atomic_dec(&system_freezing_cnt);
^~~~~~~~~~~~~~~~~~~
kernel/cgroup/freezer.c: In function 'freezer_attach':
kernel/cgroup/freezer.c:181:4: error: implicit declaration of function 'freeze_task' [-Werror=implicit-function-declaration]
freeze_task(task);
^~~~~~~~~~~
kernel/cgroup/freezer.c: In function 'freezer_apply_state':
kernel/cgroup/freezer.c:360:16: error: 'system_freezing_cnt' undeclared (first use in this function)
atomic_inc(&system_freezing_cnt);
^~~~~~~~~~~~~~~~~~~
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
We can use the generic lib to fix these error because the symbol of
libgcc in toolchain is not exported.
ERROR: "__ucmpdi2" [fs/xfs/xfs.ko] undefined!
ERROR: "__ashrdi3" [fs/xfs/xfs.ko] undefined!
ERROR: "__lshrdi3" [fs/xfs/xfs.ko] undefined!
ERROR: "__ashldi3" [fs/ntfs/ntfs.ko] undefined!
...
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
memory-barriers.txt has been updated with the following requirement.
"When using writel(), a prior wmb() is not needed to guarantee that the
cache coherent memory writes have completed before writing to the MMIO
region."
Current writeX() and iowriteX() implementations on alpha are not
satisfying this requirement as the barrier is after the register write.
Move mb() in writeX() and iowriteX() functions to guarantee that HW
observes memory changes before performing register operations.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Matt Turner <mattst88@gmail.com>
The generic dma_direct implementation does the same thing as the alpha
pci-noop implementation, just with more bells and whistles. And unlike
the current code it at least has a theoretical chance to actually compile.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Make sure to invoke pci_disable_device() when errors occur in
pcnet32_probe_pci().
Signed-off-by: Bo Chen <chenbo@pdx.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
ILT entry requires 12 bit right shifted physical address.
Existing mask for ILT entry of physical address i.e.
ILT_ENTRY_PHY_ADDR_MASK is not sufficient to handle 64bit
address because upper 8 bits of 64 bit address were getting
masked which resulted in completer abort error on
PCIe bus due to invalid address.
Fix that mask to handle 64bit physical address.
Fixes: fe56b9e6a8 ("qed: Add module with basic common support")
Signed-off-by: Shahed Shaikh <shahed.shaikh@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In divasmain.c, the function divas_write() firstly invokes the function
diva_xdi_open_adapter() to open the adapter that matches with the adapter
number provided by the user, and then invokes the function diva_xdi_write()
to perform the write operation using the matched adapter. The two functions
diva_xdi_open_adapter() and diva_xdi_write() are located in diva.c.
In diva_xdi_open_adapter(), the user command is copied to the object 'msg'
from the userspace pointer 'src' through the function pointer 'cp_fn',
which eventually calls copy_from_user() to do the copy. Then, the adapter
number 'msg.adapter' is used to find out a matched adapter from the
'adapter_queue'. A matched adapter will be returned if it is found.
Otherwise, NULL is returned to indicate the failure of the verification on
the adapter number.
As mentioned above, if a matched adapter is returned, the function
diva_xdi_write() is invoked to perform the write operation. In this
function, the user command is copied once again from the userspace pointer
'src', which is the same as the 'src' pointer in diva_xdi_open_adapter() as
both of them are from the 'buf' pointer in divas_write(). Similarly, the
copy is achieved through the function pointer 'cp_fn', which finally calls
copy_from_user(). After the successful copy, the corresponding command
processing handler of the matched adapter is invoked to perform the write
operation.
It is obvious that there are two copies here from userspace, one is in
diva_xdi_open_adapter(), and one is in diva_xdi_write(). Plus, both of
these two copies share the same source userspace pointer, i.e., the 'buf'
pointer in divas_write(). Given that a malicious userspace process can race
to change the content pointed by the 'buf' pointer, this can pose potential
security issues. For example, in the first copy, the user provides a valid
adapter number to pass the verification process and a valid adapter can be
found. Then the user can modify the adapter number to an invalid number.
This way, the user can bypass the verification process of the adapter
number and inject inconsistent data.
This patch reuses the data copied in
diva_xdi_open_adapter() and passes it to diva_xdi_write(). This way, the
above issues can be avoided.
Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently there is no license information in the header of
this file.
The MODULE_LICENSE field contains ("GPL"), which means
GNU Public License v2 or later, so add a corresponding
SPDX license identifier.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now sctp uses inet_dgram_connect as its proto_ops .connect, and the flags
param can't be passed into its proto .connect where this flags is really
needed.
sctp works around it by getting flags from socket file in __sctp_connect.
It works for connecting from userspace, as inherently the user sock has
socket file and it passes f_flags as the flags param into the proto_ops
.connect.
However, the sock created by sock_create_kern doesn't have a socket file,
and it passes the flags (like O_NONBLOCK) by using the flags param in
kernel_connect, which calls proto_ops .connect later.
So to fix it, this patch defines a new proto_ops .connect for sctp,
sctp_inet_connect, which calls __sctp_connect() directly with this
flags param. After this, the sctp's proto .connect can be removed.
Note that sctp_inet_connect doesn't need to do some checks that are not
needed for sctp, which makes thing better than with inet_dgram_connect.
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
If userspace faults on a kernel address, handing them the raw ESR
value on the sigframe as part of the delivered signal can leak data
useful to attackers who are using information about the underlying hardware
fault type (e.g. translation vs permission) as a mechanism to defeat KASLR.
However there are also legitimate uses for the information provided
in the ESR -- notably the GCC and LLVM sanitizers use this to report
whether wild pointer accesses by the application are reads or writes
(since a wild write is a more serious bug than a wild read), so we
don't want to drop the ESR information entirely.
For faulting addresses in the kernel, sanitize the ESR. We choose
to present userspace with the illusion that there is nothing mapped
in the kernel's part of the address space at all, by reporting all
faults as level 0 translation faults taken to EL1.
These fields are safe to pass through to userspace as they depend
only on the instruction that userspace used to provoke the fault:
EC IL (always)
ISV CM WNR (for all data aborts)
All the other fields in ESR except DFSC are architecturally RES0
for an L0 translation fault taken to EL1, so can be zeroed out
without confusing userspace.
The illusion is not entirely perfect, as there is a tiny wrinkle
where we will report an alignment fault that was not due to the memory
type (for instance a LDREX to an unaligned address) as a translation
fault, whereas if you do this on real unmapped memory the alignment
fault takes precedence. This is not likely to trip anybody up in
practice, as the only users we know of for the ESR information who
care about the behaviour for kernel addresses only really want to
know about the WnR bit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Commit 08810a4119 (PM / core: Add NEVER_SKIP and SMART_PREPARE
driver flags) inadvertently prevented the power.direct_complete flag
from being set for devices without PM callbacks and with disabled
runtime PM which also prevents power.direct_complete from being set
for their parents. That led to problems including a resume crash on
HP ZBook 14u.
Restore the previous behavior by causing power.direct_complete to be
set for those devices again, but do that in a more direct way to
avoid overlooking that case in the future.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199693
Fixes: 08810a4119 (PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags)
Reported-by: Thomas Martitz <kugel@rockbox.org>
Tested-by: Thomas Martitz <kugel@rockbox.org>
Cc: 4.15+ <stable@vger.kernel.org> # 4.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Johan Hovold <johan@kernel.org>
Since 6335698e24 the radio with idx of 0
will not get dumped in HWSIM_CMD_GET_RADIO because of the last_idx
checks. Offset cb->args[0] by 1 similarly to what is done in nl80211.c.
Fixes: 6335698e24 ("mac80211_hwsim: add generation count for netlink dump operation")
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some drivers may call this function when regdb is not initialized yet,
so we need to make sure regdb is valid before trying to access it.
Make sure regdb is initialized before trying to access it in
reg_query_regdb_wmm() and query_regdb().
Reported-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Haim Dreyfuss <haim.dreyfuss@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.
This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.
Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.
Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.
Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.
Thanks to Michal Suchánek for bug fixes and review.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Single regression fix for rcar-du lvds
* 'drm/du/fixes' of git://linuxtv.org/pinchartl/media:
drm: rcar-du: lvds: Fix crash in .atomic_check when disabling connector
Two driver fixes (zfcp and target core), one information leak in sg
and one build clean up.
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Two driver fixes (zfcp and target core), one information leak in sg
and one build clean up"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()
scsi: core: clean up generated file scsi_devinfo_tbl.c
scsi: target: tcmu: fix error resetting qfull_time_out to default
scsi: zfcp: fix infinite iteration on ERP ready list
Pull vfs fixes from Al Viro:
"Assorted fixes all over the place"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
aio: fix io_destroy(2) vs. lookup_ioctx() race
ext2: fix a block leak
nfsd: vfs_mkdir() might succeed leaving dentry negative unhashed
cachefiles: vfs_mkdir() might succeed leaving dentry negative unhashed
unfuck sysfs_mount()
kernfs: deal with kernfs_fill_super() failures
cramfs: Fix IS_ENABLED typo
befs_lookup(): use d_splice_alias()
affs_lookup: switch to d_splice_alias()
affs_lookup(): close a race with affs_remove_link()
fix breakage caused by d_find_alias() semantics change
fs: don't scan the inode cache before SB_BORN is set
do d_instantiate/unlock_new_inode combinations safely
iov_iter: fix memory leak in pipe_get_pages_alloc()
iov_iter: fix return type of __pipe_get_pages()
When a loop block device encounters a writeback error, that error will
get propagated to the bd_inode's wb_err field. If we then detach the
backing file from it, attach another and fsync it, we'll get back the
writeback error that we had from the previous backing file.
This is a bit of a grey area as POSIX doesn't cover loop devices, but it
is somewhat counterintuitive.
If we detach a backing file from the loopdev while there are still
unreported errors, take it as a sign that we're no longer interested in
the previous file, and clear out the wb_err in the loop blockdev.
Reported-and-Tested-by: Theodore Y. Ts'o <tytso@mit.edu>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
kill_ioctx() used to have an explicit RCU delay between removing the
reference from ->ioctx_table and percpu_ref_kill() dropping the refcount.
At some point that delay had been removed, on the theory that
percpu_ref_kill() itself contained an RCU delay. Unfortunately, that was
the wrong kind of RCU delay and it didn't care about rcu_read_lock() used
by lookup_ioctx(). As the result, we could get ctx freed right under
lookup_ioctx(). Tejun has fixed that in a6d7cff472 ("fs/aio: Add explicit
RCU grace period when freeing kioctx"); however, that fix is not enough.
Suppose io_destroy() from one thread races with e.g. io_setup() from another;
CPU1 removes the reference from current->mm->ioctx_table[...] just as CPU2
has picked it (under rcu_read_lock()). Then CPU1 proceeds to drop the
refcount, getting it to 0 and triggering a call of free_ioctx_users(),
which proceeds to drop the secondary refcount and once that reaches zero
calls free_ioctx_reqs(). That does
INIT_RCU_WORK(&ctx->free_rwork, free_ioctx);
queue_rcu_work(system_wq, &ctx->free_rwork);
and schedules freeing the whole thing after RCU delay.
In the meanwhile CPU2 has gotten around to percpu_ref_get(), bumping the
refcount from 0 to 1 and returned the reference to io_setup().
Tejun's fix (that queue_rcu_work() in there) guarantees that ctx won't get
freed until after percpu_ref_get(). Sure, we'd increment the counter before
ctx can be freed. Now we are out of rcu_read_lock() and there's nothing to
stop freeing of the whole thing. Unfortunately, CPU2 assumes that since it
has grabbed the reference, ctx is *NOT* going away until it gets around to
dropping that reference.
The fix is obvious - use percpu_ref_tryget_live() and treat failure as miss.
It's not costlier than what we currently do in normal case, it's safe to
call since freeing *is* delayed and it closes the race window - either
lookup_ioctx() comes before percpu_ref_kill() (in which case ctx->users
won't reach 0 until the caller of lookup_ioctx() drops it) or lookup_ioctx()
fails, ctx->users is unaffected and caller of lookup_ioctx() doesn't see
the object in question at all.
Cc: stable@kernel.org
Fixes: a6d7cff472 "fs/aio: Add explicit RCU grace period when freeing kioctx"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
open file, unlink it, then use ioctl(2) to make it immutable or
append only. Now close it and watch the blocks *not* freed...
Immutable/append-only checks belong in ->setattr().
Note: the bug is old and backport to anything prior to 737f2e93b9
("ext2: convert to use the new truncate convention") will need
these checks lifted into ext2_setattr().
Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.
Some vfs_mkdir() callers forget about that possibility...
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
That can (and does, on some filesystems) happen - ->mkdir() (and thus
vfs_mkdir()) can legitimately leave its argument negative and just
unhash it, counting upon the lookup to pick the object we'd created
next time we try to look at that name.
Some vfs_mkdir() callers forget about that possibility...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Thomas Hellstrom
Anders Roxell
Dominik Brodowski
Konrad Rzeszutek Wilk
Brian Norris
Vincent Chen
Nickhu
Greentime Hu
Sinan Kaya
Christoph Hellwig
Bo Chen
Shahed Shaikh
Eric Dumazet
Alexey Kodanev
Wenwen Wang
Fabio Estevam
Xin Long
Peter Maydell
Rafael J. Wysocki
Kalle Valo
Andrew Zaborowski
Haim Dreyfuss
Nicholas Piggin
Dave Airlie
Linus Torvalds
Jeff Layton
Al Viro