13 Feb, 2019
1 commit
-
[ Upstream commit df44b479654f62b478c18ee4d8bc4e9f897a9844 ]
Propagate error code back to userspace if writing the /sys/.../uevent
file fails. Before, the write operation always returned with success,
even if we failed to recognize the input string or if we failed to
generate the uevent itself.With the error codes properly propagated back to userspace, we are
able to react in userspace accordingly by not assuming and awaiting
a uevent that is not delivered.Signed-off-by: Peter Rajnoha
Signed-off-by: Greg Kroah-Hartman
Signed-off-by: Sasha Levin
23 Aug, 2018
1 commit
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An ordinary arm64 defconfig build has ~64 KB worth of __ksymtab entries,
each consisting of two 64-bit fields containing absolute references, to
the symbol itself and to a char array containing its name, respectively.When we build the same configuration with KASLR enabled, we end up with an
additional ~192 KB of relocations in the .init section, i.e., one 24 byte
entry for each absolute reference, which all need to be processed at boot
time.Given how the struct kernel_symbol that describes each entry is completely
local to module.c (except for the references emitted by EXPORT_SYMBOL()
itself), we can easily modify it to contain two 32-bit relative references
instead. This reduces the size of the __ksymtab section by 50% for all
64-bit architectures, and gets rid of the runtime relocations entirely for
architectures implementing KASLR, either via standard PIE linking (arm64)
or using custom host tools (x86).Note that the binary search involving __ksymtab contents relies on each
section being sorted by symbol name. This is implemented based on the
input section names, not the names in the ksymtab entries, so this patch
does not interfere with that.Given that the use of place-relative relocations requires support both in
the toolchain and in the module loader, we cannot enable this feature for
all architectures. So make it dependent on whether
CONFIG_HAVE_ARCH_PREL32_RELOCATIONS is defined.Link: http://lkml.kernel.org/r/20180704083651.24360-4-ard.biesheuvel@linaro.org
Signed-off-by: Ard Biesheuvel
Acked-by: Jessica Yu
Acked-by: Michael Ellerman
Reviewed-by: Will Deacon
Acked-by: Ingo Molnar
Cc: Arnd Bergmann
Cc: Benjamin Herrenschmidt
Cc: Bjorn Helgaas
Cc: Catalin Marinas
Cc: James Morris
Cc: James Morris
Cc: Josh Poimboeuf
Cc: Kees Cook
Cc: Nicolas Pitre
Cc: Paul Mackerras
Cc: Petr Mladek
Cc: Russell King
Cc: "Serge E. Hallyn"
Cc: Sergey Senozhatsky
Cc: Steven Rostedt
Cc: Thomas Garnier
Cc: Thomas Gleixner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Aug, 2018
1 commit
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Pull modules updates from Jessica Yu:
"Summary of modules changes for the 4.19 merge window:- Fix modules kallsyms for livepatch. Livepatch modules can have
SHN_UNDEF symbols in their module symbol tables for later symbol
resolution, but kallsyms shouldn't be returning these symbols- Some code cleanups and minor reshuffling in load_module() were done
to log the module name when module signature verification fails"* tag 'modules-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
kernel/module: Use kmemdup to replace kmalloc+memcpy
ARM: module: fix modsign build error
modsign: log module name in the event of an error
module: replace VMLINUX_SYMBOL_STR() with __stringify() or string literal
module: print sensible error code
module: setup load info before module_sig_check()
module: make it clear when we're handling the module copy in info->hdr
module: exclude SHN_UNDEF symbols from kallsyms api
03 Aug, 2018
1 commit
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we prefer to the kmemdup rather than kmalloc+memcpy. so just
replace them.Signed-off-by: zhong jiang
Signed-off-by: Jessica Yu
17 Jul, 2018
1 commit
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Both the init_module and finit_module syscalls call either directly
or indirectly the security_kernel_read_file LSM hook. This patch
replaces the direct call in init_module with a call to the new
security_kernel_load_data hook and makes the corresponding changes
in SELinux, LoadPin, and IMA.Signed-off-by: Mimi Zohar
Cc: Jeff Vander Stoep
Cc: Casey Schaufler
Cc: Kees Cook
Acked-by: Jessica Yu
Acked-by: Paul Moore
Acked-by: Kees Cook
Signed-off-by: James Morris
02 Jul, 2018
1 commit
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Now that we have the load_info struct all initialized (including
info->name, which contains the name of the module) before
module_sig_check(), make the load_info struct and hence module name
available to mod_verify_sig() so that we can log the module name in the
event of an error.Signed-off-by: Jessica Yu
25 Jun, 2018
2 commits
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With the special case handling for Blackfin and Metag was removed by
commit 94e58e0ac312 ("export.h: remove code for prefixing symbols with
underscore"), VMLINUX_SYMBOL_STR() is now equivalent to __stringify().Replace the remaining usages to prepare for the entire removal of
VMLINUX_SYMBOL_STR().Signed-off-by: Masahiro Yamada
Signed-off-by: Jessica Yu -
Printing "err 0" to the user in the warning message is not particularly
useful, especially when this gets transformed into a -ENOENT for the
remainder of the call chain.Signed-off-by: Jason A. Donenfeld
Signed-off-by: Jessica Yu
22 Jun, 2018
2 commits
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We want to be able to log the module name in early error messages, such as
when module signature verification fails. Previously, the module name is
set in layout_and_allocate(), meaning that any error messages that happen
before (such as those in module_sig_check()) won't be logged with a module
name, which isn't terribly helpful.In order to do this, reshuffle the order in load_module() and set up
load info earlier so that we can log the module name along with these
error messages. This requires splitting rewrite_section_headers() out of
setup_load_info().While we're at it, clean up and split up the operations done in
layout_and_allocate(), setup_load_info(), and rewrite_section_headers()
more cleanly so these functions only perform what their names suggest.Signed-off-by: Jessica Yu
-
In load_module(), it's not always clear whether we're handling the
temporary module copy in info->hdr (which is freed at the end of
load_module()) or if we're handling the module already allocated and
copied to it's final place. Adding an info->mod field and using it
whenever we're handling the temporary copy makes that explicitly clear.Signed-off-by: Jessica Yu
18 Jun, 2018
1 commit
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Livepatch modules are special in that we preserve their entire symbol
tables in order to be able to apply relocations after module load. The
unwanted side effect of this is that undefined (SHN_UNDEF) symbols of
livepatch modules are accessible via the kallsyms api and this can
confuse symbol resolution in livepatch (klp_find_object_symbol()) and
cause subtle bugs in livepatch.Have the module kallsyms api skip over SHN_UNDEF symbols. These symbols
are usually not available for normal modules anyway as we cut down their
symbol tables to just the core (non-undefined) symbols, so this should
really just affect livepatch modules. Note that this patch doesn't
affect the display of undefined symbols in /proc/kallsyms.Reported-by: Josh Poimboeuf
Tested-by: Josh Poimboeuf
Reviewed-by: Josh Poimboeuf
Signed-off-by: Jessica Yu
16 Jun, 2018
1 commit
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Pull module updates from Jessica Yu:
"Minor code cleanup and also allow sig_enforce param to be shown in
sysfs with CONFIG_MODULE_SIG_FORCE"* tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Allow to always show the status of modsign
module: Do not access sig_enforce directly
07 Jun, 2018
2 commits
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Pull overflow updates from Kees Cook:
"This adds the new overflow checking helpers and adds them to the
2-factor argument allocators. And this adds the saturating size
helpers and does a treewide replacement for the struct_size() usage.
Additionally this adds the overflow testing modules to make sure
everything works.I'm still working on the treewide replacements for allocators with
"simple" multiplied arguments:*alloc(a * b, ...) -> *alloc_array(a, b, ...)
and
*zalloc(a * b, ...) -> *calloc(a, b, ...)
as well as the more complex cases, but that's separable from this
portion of the series. I expect to have the rest sent before -rc1
closes; there are a lot of messy cases to clean up.Summary:
- Introduce arithmetic overflow test helper functions (Rasmus)
- Use overflow helpers in 2-factor allocators (Kees, Rasmus)
- Introduce overflow test module (Rasmus, Kees)
- Introduce saturating size helper functions (Matthew, Kees)
- Treewide use of struct_size() for allocators (Kees)"
* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
treewide: Use struct_size() for devm_kmalloc() and friends
treewide: Use struct_size() for vmalloc()-family
treewide: Use struct_size() for kmalloc()-family
device: Use overflow helpers for devm_kmalloc()
mm: Use overflow helpers in kvmalloc()
mm: Use overflow helpers in kmalloc_array*()
test_overflow: Add memory allocation overflow tests
overflow.h: Add allocation size calculation helpers
test_overflow: Report test failures
test_overflow: macrofy some more, do more tests for free
lib: add runtime test of check_*_overflow functions
compiler.h: enable builtin overflow checkers and add fallback code -
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:struct foo {
int stuff;
void *entry[];
};instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);
This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
// sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)Signed-off-by: Kees Cook
12 May, 2018
1 commit
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load_module() creates W+X mappings via __vmalloc_node_range() (from
layout_and_allocate()->move_module()->module_alloc()) by using
PAGE_KERNEL_EXEC. These mappings are later cleaned up via
"call_rcu_sched(&freeinit->rcu, do_free_init)" from do_init_module().This is a problem because call_rcu_sched() queues work, which can be run
after debug_checkwx() is run, resulting in a race condition. If hit,
the race results in a nasty splat about insecure W+X mappings, which
results in a poor user experience as these are not the mappings that
debug_checkwx() is intended to catch.This issue is observed on multiple arm64 platforms, and has been
artificially triggered on an x86 platform.Address the race by flushing the queued work before running the
arch-defined mark_rodata_ro() which then calls debug_checkwx().Link: http://lkml.kernel.org/r/1525103946-29526-1-git-send-email-jhugo@codeaurora.org
Fixes: e1a58320a38d ("x86/mm: Warn on W^X mappings")
Signed-off-by: Jeffrey Hugo
Reported-by: Timur Tabi
Reported-by: Jan Glauber
Acked-by: Kees Cook
Acked-by: Ingo Molnar
Acked-by: Will Deacon
Acked-by: Laura Abbott
Cc: Mark Rutland
Cc: Ard Biesheuvel
Cc: Catalin Marinas
Cc: Stephen Smalley
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
19 Apr, 2018
1 commit
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Reading file /proc/modules shows the correct address:
[root@s35lp76 ~]# cat /proc/modules | egrep '^qeth_l2'
qeth_l2 94208 1 - Live 0x000003ff80401000and reading file /sys/module/qeth_l2/sections/.text
[root@s35lp76 ~]# cat /sys/module/qeth_l2/sections/.text
0x0000000018ea8363
displays a random address.This breaks the perf tool which uses this address on s390
to calculate start of .text section in memory.Fix this by printing the correct (unhashed) address.
Thanks to Jessica Yu for helping on this.
Fixes: ef0010a30935 ("vsprintf: don't use 'restricted_pointer()' when not restricting")
Cc: # v4.15+
Suggested-by: Linus Torvalds
Signed-off-by: Thomas Richter
Cc: Jessica Yu
Signed-off-by: Jessica Yu
17 Apr, 2018
2 commits
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The sig_enforce parameter could be always shown to reflect the current
status of signature enforcement. For the case of
CONFIG_MODULE_SIG_FORCE=y, this modification doesn't do anything, since
sig_enforce can only be enabled, and not disabled, even via the kernel
cmdline.Signed-off-by: Jia Zhang
[jeyu: reworded commit message to provide clarification]
Signed-off-by: Jessica Yu -
Call is_module_sig_enforced() instead.
Signed-off-by: Jia Zhang
Signed-off-by: Jessica Yu
03 Apr, 2018
1 commit
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Pul removal of obsolete architecture ports from Arnd Bergmann:
"This removes the entire architecture code for blackfin, cris, frv,
m32r, metag, mn10300, score, and tile, including the associated device
drivers.I have been working with the (former) maintainers for each one to
ensure that my interpretation was right and the code is definitely
unused in mainline kernels. Many had fond memories of working on the
respective ports to start with and getting them included in upstream,
but also saw no point in keeping the port alive without any users.In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company in
charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
seems that all the SoC product lines are still around, but have not
used the custom CPU architectures for several years at this point. In
contrast, CPU instruction sets that remain popular and have actively
maintained kernel ports tend to all be used across multiple licensees.[ See the new nds32 port merged in the previous commit for the next
generation of "one company in charge of an SoC line, a CPU
microarchitecture and a software ecosystem" - Linus ]The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I
made sure that they are all unused. Some architectures (notably tile,
mn10300, and blackfin) are still being shipped in products with old
kernels, but those products will never be updated to newer kernel
releases.After this series, we still have a few architectures without mainline
gcc support:- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.- openrisc, risc-v and nds32 are still in the process of finishing
their support or getting it added to mainline gcc in the first
place. They all have patched gcc-7.3 ports that work to some
degree, but complete upstream support won't happen before gcc-8.1.
Csky posted their first kernel patch set last week, their situation
will be similar[ Palmer Dabbelt points out that RISC-V support is in mainline gcc
since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]"This really says it all:
2498 files changed, 95 insertions(+), 467668 deletions(-)
* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
MAINTAINERS: UNICORE32: Change email account
staging: iio: remove iio-trig-bfin-timer driver
tty: hvc: remove tile driver
tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
serial: remove tile uart driver
serial: remove m32r_sio driver
serial: remove blackfin drivers
serial: remove cris/etrax uart drivers
usb: Remove Blackfin references in USB support
usb: isp1362: remove blackfin arch glue
usb: musb: remove blackfin port
usb: host: remove tilegx platform glue
pwm: remove pwm-bfin driver
i2c: remove bfin-twi driver
spi: remove blackfin related host drivers
watchdog: remove bfin_wdt driver
can: remove bfin_can driver
mmc: remove bfin_sdh driver
input: misc: remove blackfin rotary driver
input: keyboard: remove bf54x driver
...
16 Mar, 2018
1 commit
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The CONFIG_MPU option was only defined on blackfin, and that architecture
is now being removed, so the respective code can be simplified.A lot of other microcontrollers have an MPU, but I suspect that if we
want to bring that support back, we'd do it differently anyway.Signed-off-by: Arnd Bergmann
09 Mar, 2018
1 commit
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otherwise kernel can oops later in seq_release() due to dereferencing null
file->private_data which is only set if seq_open() succeeds.BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
IP: seq_release+0xc/0x30
Call Trace:
close_pdeo+0x37/0xd0
proc_reg_release+0x5d/0x60
__fput+0x9d/0x1d0
____fput+0x9/0x10
task_work_run+0x75/0x90
do_exit+0x252/0xa00
do_group_exit+0x36/0xb0
SyS_exit_group+0xf/0x10Fixes: 516fb7f2e73d ("/proc/module: use the same logic as /proc/kallsyms for address exposure")
Cc: Jessica Yu
Cc: Linus Torvalds
Cc: stable@vger.kernel.org # 4.15+
Signed-off-by: Leon Yu
Signed-off-by: Jessica Yu
08 Feb, 2018
1 commit
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Pull modules updates from Jessica Yu:
"Minor code cleanups and MAINTAINERS update"* tag 'modules-for-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
modpost: Remove trailing semicolon
ftrace/module: Move ftrace_release_mod() to ddebug_cleanup label
MAINTAINERS: Remove from module & paravirt maintenance
02 Feb, 2018
1 commit
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Pull printk updates from Petr Mladek:
- Add a console_msg_format command line option:
The value "default" keeps the old "[time stamp] text\n" format. The
value "syslog" allows to see the syslog-like "[timestamp] text" format.This feature was requested by people doing regression tests, for
example, 0day robot. They want to have both filtered and full logs
at hands.- Reduce the risk of softlockup:
Pass the console owner in a busy loop.
This is a new approach to the old problem. It was first proposed by
Steven Rostedt on Kernel Summit 2017. It marks a context in which
the console_lock owner calls console drivers and could not sleep.
On the other side, printk() callers could detect this state and use
a busy wait instead of a simple console_trylock(). Finally, the
console_lock owner checks if there is a busy waiter at the end of
the special context and eventually passes the console_lock to the
waiter.The hand-off works surprisingly well and helps in many situations.
Well, there is still a possibility of the softlockup, for example,
when the flood of messages stops and the last owner still has too
much to flush.There is increasing number of people having problems with
printk-related softlockups. We might eventually need to get better
solution. Anyway, this looks like a good start and promising
direction.- Do not allow to schedule in console_unlock() called from printk():
This reverts an older controversial commit. The reschedule helped
to avoid softlockups. But it also slowed down the console output.
This patch is obsoleted by the new console waiter logic described
above. In fact, the reschedule made the hand-off less effective.- Deprecate "%pf" and "%pF" format specifier:
It was needed on ia64, ppc64 and parisc64 to dereference function
descriptors and show the real function address. It is done
transparently by "%ps" and "pS" format specifier now.Sergey Senozhatsky found that all the function descriptors were in
a special elf section and could be easily detected.- Remove printk_symbol() API:
It has been obsoleted by "%pS" format specifier, and this change
helped to remove few continuous lines and a less intuitive old API.- Remove redundant memsets:
Sergey removed unnecessary memset when processing printk.devkmsg
command line option.* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (27 commits)
printk: drop redundant devkmsg_log_str memsets
printk: Never set console_may_schedule in console_trylock()
printk: Hide console waiter logic into helpers
printk: Add console owner and waiter logic to load balance console writes
kallsyms: remove print_symbol() function
checkpatch: add pF/pf deprecation warning
symbol lookup: introduce dereference_symbol_descriptor()
parisc64: Add .opd based function descriptor dereference
powerpc64: Add .opd based function descriptor dereference
ia64: Add .opd based function descriptor dereference
sections: split dereference_function_descriptor()
openrisc: Fix conflicting types for _exext and _stext
lib: do not use print_symbol()
irq debug: do not use print_symbol()
sysfs: do not use print_symbol()
drivers: do not use print_symbol()
x86: do not use print_symbol()
unicore32: do not use print_symbol()
sh: do not use print_symbol()
mn10300: do not use print_symbol()
...
01 Feb, 2018
1 commit
-
Pull networking updates from David Miller:
1) Significantly shrink the core networking routing structures. Result
of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf2) Add netdevsim driver for testing various offloads, from Jakub
Kicinski.3) Support cross-chip FDB operations in DSA, from Vivien Didelot.
4) Add a 2nd listener hash table for TCP, similar to what was done for
UDP. From Martin KaFai Lau.5) Add eBPF based queue selection to tun, from Jason Wang.
6) Lockless qdisc support, from John Fastabend.
7) SCTP stream interleave support, from Xin Long.
8) Smoother TCP receive autotuning, from Eric Dumazet.
9) Lots of erspan tunneling enhancements, from William Tu.
10) Add true function call support to BPF, from Alexei Starovoitov.
11) Add explicit support for GRO HW offloading, from Michael Chan.
12) Support extack generation in more netlink subsystems. From Alexander
Aring, Quentin Monnet, and Jakub Kicinski.13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
Russell King.14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.
15) Many improvements and simplifications to the NFP driver bpf JIT,
from Jakub Kicinski.16) Support for ipv6 non-equal cost multipath routing, from Ido
Schimmel.17) Add resource abstration to devlink, from Arkadi Sharshevsky.
18) Packet scheduler classifier shared filter block support, from Jiri
Pirko.19) Avoid locking in act_csum, from Davide Caratti.
20) devinet_ioctl() simplifications from Al viro.
21) More TCP bpf improvements from Lawrence Brakmo.
22) Add support for onlink ipv6 route flag, similar to ipv4, from David
Ahern.* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
tls: Add support for encryption using async offload accelerator
ip6mr: fix stale iterator
net/sched: kconfig: Remove blank help texts
openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
tcp_nv: fix potential integer overflow in tcpnv_acked
r8169: fix RTL8168EP take too long to complete driver initialization.
qmi_wwan: Add support for Quectel EP06
rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
ipmr: Fix ptrdiff_t print formatting
ibmvnic: Wait for device response when changing MAC
qlcnic: fix deadlock bug
tcp: release sk_frag.page in tcp_disconnect
ipv4: Get the address of interface correctly.
net_sched: gen_estimator: fix lockdep splat
net: macb: Handle HRESP error
net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
ipv6: addrconf: break critical section in addrconf_verify_rtnl()
ipv6: change route cache aging logic
i40e/i40evf: Update DESC_NEEDED value to reflect larger value
bnxt_en: cleanup DIM work on device shutdown
...
30 Jan, 2018
1 commit
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Pull x86/pti updates from Thomas Gleixner:
"Another set of melted spectrum related changes:- Code simplifications and cleanups for RSB and retpolines.
- Make the indirect calls in KVM speculation safe.
- Whitelist CPUs which are known not to speculate from Meltdown and
prepare for the new CPUID flag which tells the kernel that a CPU is
not affected.- A less rigorous variant of the module retpoline check which merily
warns when a non-retpoline protected module is loaded and reflects
that fact in the sysfs file.- Prepare for Indirect Branch Prediction Barrier support.
- Prepare for exposure of the Speculation Control MSRs to guests, so
guest OSes which depend on those "features" can use them. Includes
a blacklist of the broken microcodes. The actual exposure of the
MSRs through KVM is still being worked on"* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Simplify indirect_branch_prediction_barrier()
x86/retpoline: Simplify vmexit_fill_RSB()
x86/cpufeatures: Clean up Spectre v2 related CPUID flags
x86/cpu/bugs: Make retpoline module warning conditional
x86/bugs: Drop one "mitigation" from dmesg
x86/nospec: Fix header guards names
x86/alternative: Print unadorned pointers
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
x86/msr: Add definitions for new speculation control MSRs
x86/cpufeatures: Add AMD feature bits for Speculation Control
x86/cpufeatures: Add Intel feature bits for Speculation Control
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
module/retpoline: Warn about missing retpoline in module
KVM: VMX: Make indirect call speculation safe
KVM: x86: Make indirect calls in emulator speculation safe
26 Jan, 2018
1 commit
-
There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen
Signed-off-by: Thomas Gleixner
Cc: David Woodhouse
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
16 Jan, 2018
1 commit
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ftrace_module_init happen after dynamic_debug_setup, it is desired that
cleanup should be called after this label however in current implementation
it is called in free module label,ie:even though ftrace in not initialized,
from so many fail case ftrace_release_mod() will be called and unnecessary
traverse the whole list.
In below patch we moved ftrace_release_mod() from free_module label to
ddebug_cleanup label. that is the best possible location, other solution
is to make new label to ftrace_release_mod() but since ftrace_module_init()
is not return with minimum changes it should be in ddebug_cleanup label.Signed-off-by: Namit Gupta
Reviewed-by: Steven Rostedt (VMware)
Signed-off-by: Jessica Yu
13 Jan, 2018
1 commit
-
Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.Some differences has been made:
- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
feature. It is automatically enabled if the arch supports
error injection feature for kprobe or ftrace etc.Signed-off-by: Masami Hiramatsu
Reviewed-by: Josef Bacik
Signed-off-by: Alexei Starovoitov
09 Jan, 2018
1 commit
-
There are two format specifiers to print out a pointer in symbolic
format: '%pS/%ps' and '%pF/%pf'. On most architectures, the two
mean exactly the same thing, but some architectures (ia64, ppc64,
parisc64) use an indirect pointer for C function pointers, where
the function pointer points to a function descriptor (which in
turn contains the actual pointer to the code). The '%pF/%pf, when
used appropriately, automatically does the appropriate function
descriptor dereference on such architectures.The "when used appropriately" part is tricky. Basically this is
a subtle ABI detail, specific to some platforms, that made it to
the API level and people can be unaware of it and miss the whole
"we need to dereference the function" business out. [1] proves
that point (note that it fixes only '%pF' and '%pS', there might
be '%pf' and '%ps' cases as well).It appears that we can handle everything within the affected
arches and make '%pS/%ps' smart enough to retire '%pF/%pf'.
Function descriptors live in .opd elf section and all affected
arches (ia64, ppc64, parisc64) handle it properly for kernel
and modules. So we, technically, can decide if the dereference
is needed by simply looking at the pointer: if it belongs to
.opd section then we need to dereference it.The kernel and modules have their own .opd sections, obviously,
that's why we need to split dereference_function_descriptor()
and use separate kernel and module dereference arch callbacks.This patch does the first step, it
a) adds dereference_kernel_function_descriptor() function.
b) adds a weak alias to dereference_module_function_descriptor()
function.So, for the time being, we will have:
1) dereference_function_descriptor()
A generic function, that simply dereferences the pointer. There is
bunch of places that call it: kgdbts, init/main.c, extable, etc.2) dereference_kernel_function_descriptor()
A function to call on kernel symbols that does kernel .opd section
address range test.3) dereference_module_function_descriptor()
A function to call on modules' symbols that does modules' .opd
section address range test.[1] https://marc.info/?l=linux-kernel&m=150472969730573
Link: http://lkml.kernel.org/r/20171109234830.5067-2-sergey.senozhatsky@gmail.com
To: Fenghua Yu
To: Benjamin Herrenschmidt
To: Paul Mackerras
To: Michael Ellerman
To: James Bottomley
Cc: Andrew Morton
Cc: Jessica Yu
Cc: Steven Rostedt
Cc: linux-ia64@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sergey Senozhatsky
Tested-by: Tony Luck #ia64
Tested-by: Santosh Sivaraj #powerpc
Tested-by: Helge Deller #parisc64
Signed-off-by: Petr Mladek
13 Dec, 2017
1 commit
-
Using BPF we can override kprob'ed functions and return arbitrary
values. Obviously this can be a bit unsafe, so make this feature opt-in
for functions. Simply tag a function with KPROBE_ERROR_INJECT_SYMBOL in
order to give BPF access to that function for error injection purposes.Signed-off-by: Josef Bacik
Acked-by: Ingo Molnar
Signed-off-by: Alexei Starovoitov
30 Nov, 2017
1 commit
-
The conditional kallsym hex printing used a special fixed-width '%lx'
output (KALLSYM_FMT) in preparation for the hashing of %p, but that
series ended up adding a %px specifier to help with the conversions.Use it, and avoid the "print pointer as an unsigned long" code.
Signed-off-by: Linus Torvalds
18 Nov, 2017
1 commit
-
Pull tracing updates from
- allow module init functions to be traced
- clean up some unused or not used by config events (saves space)
- clean up of trace histogram code
- add support for preempt and interrupt enabled/disable events
- other various clean ups
* tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits)
tracing, thermal: Hide cpu cooling trace events when not in use
tracing, thermal: Hide devfreq trace events when not in use
ftrace: Kill FTRACE_OPS_FL_PER_CPU
perf/ftrace: Small cleanup
perf/ftrace: Fix function trace events
perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function")
tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on
tracing, memcg, vmscan: Hide trace events when not in use
tracing/xen: Hide events that are not used when X86_PAE is not defined
tracing: mark trace_test_buffer as __maybe_unused
printk: Remove superfluous memory barriers from printk_safe
ftrace: Clear hashes of stale ips of init memory
tracing: Add support for preempt and irq enable/disable events
tracing: Prepare to add preempt and irq trace events
ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions
ftrace: Add freeing algorithm to free ftrace_mod_maps
ftrace: Save module init functions kallsyms symbols for tracing
ftrace: Allow module init functions to be traced
ftrace: Add a ftrace_free_mem() function for modules to use
tracing: Reimplement log2
...
16 Nov, 2017
1 commit
-
Pull module updates from Jessica Yu:
"Summary of modules changes for the 4.15 merge window:- treewide module_param_call() cleanup, fix up set/get function
prototype mismatches, from Kees Cook- minor code cleanups"
* tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Do not paper over type mismatches in module_param_call()
treewide: Fix function prototypes for module_param_call()
module: Prepare to convert all module_param_call() prototypes
kernel/module: Delete an error message for a failed memory allocation in add_module_usage()
14 Nov, 2017
1 commit
-
…morris/linux-security
Pull security subsystem integrity updates from James Morris:
"There is a mixture of bug fixes, code cleanup, preparatory code for
new functionality and new functionality.Commit 26ddabfe96bb ("evm: enable EVM when X509 certificate is
loaded") enabled EVM without loading a symmetric key, but was limited
to defining the x509 certificate pathname at build. Included in this
set of patches is the ability of enabling EVM, without loading the EVM
symmetric key, from userspace. New is the ability to prevent the
loading of an EVM symmetric key."* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
ima: Remove redundant conditional operator
ima: Fix bool initialization/comparison
ima: check signature enforcement against cmdline param instead of CONFIG
module: export module signature enforcement status
ima: fix hash algorithm initialization
EVM: Only complain about a missing HMAC key once
EVM: Allow userspace to signal an RSA key has been loaded
EVM: Include security.apparmor in EVM measurements
ima: call ima_file_free() prior to calling fasync
integrity: use kernel_read_file_from_path() to read x509 certs
ima: always measure and audit files in policy
ima: don't remove the securityfs policy file
vfs: fix mounting a filesystem with i_version
13 Nov, 2017
2 commits
-
The (alleged) users of the module addresses are the same: kernel
profiling.So just expose the same helper and format macros, and unify the logic.
Signed-off-by: Linus Torvalds
-
This code goes back to the historical bitkeeper tree commit 3f7b0672086
("Module section offsets in /sys/module"), where Jonathan Corbet wanted
to show people how to debug loadable modules.See
https://lwn.net/Articles/88052/
from June 2004.
To expose the required load address information, Jonathan added the
sections subdirectory for every module in /sys/modules, and made them
S_IRUGO - readable by everybody.It was a more innocent time, plus those S_IRxxx macro names are a lot
more confusing than the octal numbers are, so maybe it wasn't even
intentional. But here we are, thirteen years later, and I'll just change
it to S_IRUSR instead.Let's see if anybody even notices.
Cc: Jonathan Corbet
Signed-off-by: Linus Torvalds
09 Nov, 2017
1 commit
-
A static variable sig_enforce is used as status var to indicate the real
value of CONFIG_MODULE_SIG_FORCE, once this one is set the var will hold
true, but if the CONFIG is not set the status var will hold whatever
value is present in the module.sig_enforce kernel cmdline param: true
when =1 and false when =0 or not present.Considering this cmdline param take place over the CONFIG value when
it's not set, other places in the kernel could misbehave since they
would have only the CONFIG_MODULE_SIG_FORCE value to rely on. Exporting
this status var allows the kernel to rely in the effective value of
module signature enforcement, being it from CONFIG value or cmdline
param.Signed-off-by: Bruno E. O. Meneguele
Signed-off-by: Mimi Zohar
19 Oct, 2017
1 commit
-
Omit an extra message for a memory allocation failure in this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring
Signed-off-by: Jessica Yu
06 Oct, 2017
2 commits
-
If function tracing is active when the module init functions are freed, then
store them to be referenced by kallsyms. As module init functions can now be
traced on module load, they were useless:># echo ':mod:snd_seq' > set_ftrace_filter
># echo function > current_tracer
># modprobe snd_seq
># cat trace
# tracer: function
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
modprobe-2786 [000] .... 3189.037874: 0xffffffffa0860000 irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
modprobe-2463 [002] .... 174.243237: alsa_seq_init -
Allow for module init sections to be traced as well as core kernel init
sections. Now that filtering modules functions can be stored, for when they
are loaded, it makes sense to be able to trace them.Cc: Jessica Yu
Cc: Rusty Russell
Signed-off-by: Steven Rostedt (VMware)
