15 Jan, 2021
1 commit
-
With ThinLTO and CFI both enabled, LLVM appends a hash to the
names of all static functions. This breaks userspace tools, so
strip out the hash from output.Bug: 145210207
Change-Id: Icc0173f1d754b378ae81a9f91d84c0814ba26b78
Suggested-by: Jack Pham
Signed-off-by: Sami Tolvanen
26 Oct, 2020
1 commit
-
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.Remove the quote operator # from compiler_attributes.h __section macro.
Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.Conversion done using the script at:
https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl
Signed-off-by: Joe Perches
Reviewed-by: Nick Desaulniers
Reviewed-by: Miguel Ojeda
Signed-off-by: Linus Torvalds
24 Aug, 2020
1 commit
-
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through
Signed-off-by: Gustavo A. R. Silva
28 Jul, 2020
1 commit
-
Signed-off-by: Ingo Molnar
09 Jul, 2020
1 commit
-
In order to perform future tests against the cred saved during open(),
switch kallsyms_show_value() to operate on a cred, and have all current
callers pass current_cred(). This makes it very obvious where callers
are checking the wrong credential in their "read" contexts. These will
be fixed in the coming patches.Additionally switch return value to bool, since it is always used as a
direct permission check, not a 0-on-success, negative-on-error style
function return.Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook
15 Jun, 2020
2 commits
-
Symbols are needed for tools to describe instruction addresses. Pages
allocated for ftrace's purposes need symbols to be created for them.
Add such symbols to be visible via /proc/kallsyms.Example on x86 with CONFIG_DYNAMIC_FTRACE=y
# echo function > /sys/kernel/debug/tracing/current_tracer
# cat /proc/kallsyms | grep '\[__builtin__ftrace\]'
ffffffffc0238000 t ftrace_trampoline [__builtin__ftrace]Note: This patch adds "__builtin__ftrace" as a module name in /proc/kallsyms for
symbols for pages allocated for ftrace's purposes, even though "__builtin__ftrace"
is not a module.Signed-off-by: Adrian Hunter
Signed-off-by: Peter Zijlstra (Intel)
Acked-by: Peter Zijlstra (Intel)
Link: https://lkml.kernel.org/r/20200512121922.8997-7-adrian.hunter@intel.com -
Symbols are needed for tools to describe instruction addresses. Pages
allocated for kprobe's purposes need symbols to be created for them.
Add such symbols to be visible via /proc/kallsyms.Note: kprobe insn pages are not used if ftrace is configured. To see the
effect of this patch, the kernel must be configured with:# CONFIG_FUNCTION_TRACER is not set
CONFIG_KPROBES=yand for optimised kprobes:
CONFIG_OPTPROBES=y
Example on x86:
# perf probe __schedule
Added new event:
probe:__schedule (on __schedule)
# cat /proc/kallsyms | grep '\[__builtin__kprobes\]'
ffffffffc00d4000 t kprobe_insn_page [__builtin__kprobes]
ffffffffc00d6000 t kprobe_optinsn_page [__builtin__kprobes]Note: This patch adds "__builtin__kprobes" as a module name in
/proc/kallsyms for symbols for pages allocated for kprobes' purposes, even
though "__builtin__kprobes" is not a module.Signed-off-by: Adrian Hunter
Signed-off-by: Peter Zijlstra (Intel)
Acked-by: Masami Hiramatsu
Link: https://lkml.kernel.org/r/20200528080058.20230-1-adrian.hunter@intel.com
08 Apr, 2020
1 commit
-
kallsyms_lookup_name() and kallsyms_on_each_symbol() are exported to
modules despite having no in-tree users and being wide open to abuse by
out-of-tree modules that can use them as a method to invoke arbitrary
non-exported kernel functions.Unexport kallsyms_lookup_name() and kallsyms_on_each_symbol().
Signed-off-by: Will Deacon
Signed-off-by: Andrew Morton
Reviewed-by: Greg Kroah-Hartman
Reviewed-by: Christoph Hellwig
Reviewed-by: Masami Hiramatsu
Reviewed-by: Quentin Perret
Acked-by: Alexei Starovoitov
Cc: Thomas Gleixner
Cc: Frederic Weisbecker
Cc: K.Prasad
Cc: Miroslav Benes
Cc: Petr Mladek
Cc: Joe Lawrence
Cc: Mathieu Desnoyers
Link: http://lkml.kernel.org/r/20200221114404.14641-4-will@kernel.org
Signed-off-by: Linus Torvalds
10 Feb, 2020
1 commit
-
Pull more Kbuild updates from Masahiro Yamada:
- fix randconfig to generate a sane .config
- rename hostprogs-y / always to hostprogs / always-y, which are more
natual syntax.- optimize scripts/kallsyms
- fix yes2modconfig and mod2yesconfig
- make multiple directory targets ('make foo/ bar/') work
* tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: make multiple directory targets work
kconfig: Invalidate all symbols after changing to y or m.
kallsyms: fix type of kallsyms_token_table[]
scripts/kallsyms: change table to store (strcut sym_entry *)
scripts/kallsyms: rename local variables in read_symbol()
kbuild: rename hostprogs-y/always to hostprogs/always-y
kbuild: fix the document to use extra-y for vmlinux.lds
kconfig: fix broken dependency in randconfig-generated .config
05 Feb, 2020
1 commit
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kallsyms_token_table[] only contains ASCII characters. It should be
char instead of u8.Signed-off-by: Masahiro Yamada
Reviewed-by: Masami Hiramatsu
04 Feb, 2020
1 commit
-
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.Conversion rule is:
llseek => proc_lseek
unlocked_ioctl => proc_ioctlxxx => proc_xxx
delete ".owner = THIS_MODULE" line
[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan
Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Aug, 2019
1 commit
-
An arm64 kernel configured with
CONFIG_KPROBES=y
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_ALL is not set
CONFIG_KALLSYMS_BASE_RELATIVE=yreports the following kprobe failure:
[ 0.032677] kprobes: failed to populate blacklist: -22
[ 0.033376] Please take care of using kprobes.It appears that kprobe fails to retrieve the symbol at address
0xffff000010081000, despite this symbol being in System.map:ffff000010081000 T __exception_text_start
This symbol is part of the first group of aliases in the
kallsyms_offsets array (symbol names generated using ugly hacks in
scripts/kallsyms.c):kallsyms_offsets:
.long 0x1000 // do_undefinstr
.long 0x1000 // efi_header_end
.long 0x1000 // _stext
.long 0x1000 // __exception_text_start
.long 0x12b0 // do_cp15instrLooking at the implementation of get_symbol_pos(), it returns the
lowest index for aliasing symbols. In this case, it return 0.But kallsyms_lookup_size_offset() considers 0 as a failure, which
is obviously wrong (there is definitely a valid symbol living there).
In turn, the kprobe blacklisting stops abruptly, hence the original
error.A CONFIG_KALLSYMS_ALL kernel wouldn't fail as there is always
some random symbols at the beginning of this array, which are never
looked up via kallsyms_lookup_size_offset.Fix it by considering that get_symbol_pos() is always successful
(which is consistent with the other uses of this function).Fixes: ffc5089196446 ("[PATCH] Create kallsyms_lookup_size_offset()")
Reviewed-by: Masami Hiramatsu
Cc: Arnaldo Carvalho de Melo
Cc: Peter Zijlstra
Cc: Will Deacon
Cc: Catalin Marinas
Signed-off-by: Marc Zyngier
Signed-off-by: Will Deacon
21 May, 2019
1 commit
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Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the fileThese files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:GPL-2.0-only
Signed-off-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
22 Jan, 2019
1 commit
-
With this patch, /proc/kallsyms will show BPF programs as
t bpf_prog__ [bpf]
Signed-off-by: Song Liu
Reviewed-by: Arnaldo Carvalho de Melo
Tested-by: Arnaldo Carvalho de Melo
Acked-by: Peter Zijlstra
Cc: Alexei Starovoitov
Cc: Daniel Borkmann
Cc: Peter Zijlstra
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-10-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo
10 Sep, 2018
1 commit
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Both kallsyms_num_syms and kallsyms_markers[] don't really need to use
unsigned long as their (base) types; unsigned int fully suffices.Signed-off-by: Jan Beulich
Signed-off-by: Masahiro Yamada
15 Aug, 2018
2 commits
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Currently, the addresses of PTI entry trampolines are not exported to
user space. Kernel profiling tools need these addresses to identify the
kernel code, so add a symbol and address for each CPU's PTI entry
trampoline.Signed-off-by: Alexander Shishkin
Acked-by: Andi Kleen
Acked-by: Peter Zijlstra (Intel)
Cc: Andy Lutomirski
Cc: Dave Hansen
Cc: H. Peter Anvin
Cc: Jiri Olsa
Cc: Joerg Roedel
Cc: Thomas Gleixner
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1528289651-4113-3-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo -
The logic in update_iter_mod() is overcomplicated and gets worse every
time another get_ksymbol_* function is added.In preparation for adding another get_ksymbol_* function, simplify logic
in update_iter_mod().Signed-off-by: Adrian Hunter
Tested-by: (ftrace changes only) Steven Rostedt (VMware)
Acked-by: Andi Kleen
Acked-by: Peter Zijlstra (Intel)
Cc: Alexander Shishkin
Cc: Andy Lutomirski
Cc: Dave Hansen
Cc: H. Peter Anvin
Cc: Jiri Olsa
Cc: Joerg Roedel
Cc: Thomas Gleixner
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1528289651-4113-2-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo
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()
...
22 Jan, 2018
1 commit
16 Jan, 2018
1 commit
-
No more print_symbol()/__print_symbol() users left, remove these
symbols.It was a very old API that encouraged people use continuous lines.
It had been obsoleted by %pS format specifier in a normal printk()
call.Link: http://lkml.kernel.org/r/20180105102538.GC471@jagdpanzerIV
Cc: Andrew Morton
Cc: Russell King
Cc: Catalin Marinas
Cc: Mark Salter
Cc: Tony Luck
Cc: David Howells
Cc: Yoshinori Sato
Cc: Guan Xuetao
Cc: Borislav Petkov
Cc: Greg Kroah-Hartman
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Vineet Gupta
Cc: Fengguang Wu
Cc: Steven Rostedt
Cc: LKML
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-am33-list@redhat.com
Cc: linux-sh@vger.kernel.org
Cc: linux-edac@vger.kernel.org
Cc: x86@kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: Sergey Senozhatsky
Signed-off-by: Sergey Senozhatsky
Suggested-by: Joe Perches
[pmladek@suse.com: updated commit message]
Signed-off-by: Petr Mladek
09 Jan, 2018
1 commit
-
dereference_symbol_descriptor() invokes appropriate ARCH specific
function descriptor dereference callbacks:
- dereference_kernel_function_descriptor() if the pointer is a
kernel symbol;- dereference_module_function_descriptor() if the pointer is a
module symbol.This is the last step needed to make '%pS/%ps' smart enough to
handle function descriptor dereference on affected ARCHs and
to retire '%pF/%pf'.To refresh it:
Some architectures (ia64, ppc64, parisc64) use an indirect pointer
for C function pointers - the function pointer points to a function
descriptor and we need to dereference it to get the actual function
pointer.Function descriptors live in .opd elf section and all affected
ARCHs (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.Link: http://lkml.kernel.org/r/20171206043649.GB15885@jagdpanzerIV
Cc: Fenghua Yu
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: 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
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
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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
...
13 Nov, 2017
1 commit
-
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
09 Nov, 2017
1 commit
-
Not only is it annoying to have one single flag for all pointers, as if
that was a global choice and all kernel pointers are the same, but %pK
can't get the 'access' vs 'open' time check right anyway.So make the /proc/kallsyms pointer value code use logic specific to that
particular file. We do continue to honor kptr_restrict, but the default
(which is unrestricted) is changed to instead take expected users into
account, and restrict access by default.Right now the only actual expected user is kernel profiling, which has a
separate sysctl flag for kernel profile access. There may be others.Signed-off-by: Linus Torvalds
06 Oct, 2017
2 commits
-
If a module is loaded while tracing is enabled, then there's a possibility
that the module init functions were traced. These functions have their name
and address stored by ftrace such that it can translate the function address
that is written into the buffer into a human readable function name.As userspace tools may be doing the same, they need a way to map function
names to their address as well. This is done through reading /proc/kallsyms.Signed-off-by: Steven Rostedt (VMware)
-
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
11 Jul, 2017
1 commit
-
'all_var' looks like a variable, but is actually a macro. Use
IS_ENABLED(CONFIG_KALLSYMS_ALL) for clarification.Link: http://lkml.kernel.org/r/1497577591-3434-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada
Cc: Alexei Starovoitov
Cc: Daniel Borkmann
Cc: "David S. Miller"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Feb, 2017
1 commit
-
Long standing issue with JITed programs is that stack traces from
function tracing check whether a given address is kernel code
through {__,}kernel_text_address(), which checks for code in core
kernel, modules and dynamically allocated ftrace trampolines. But
what is still missing is BPF JITed programs (interpreted programs
are not an issue as __bpf_prog_run() will be attributed to them),
thus when a stack trace is triggered, the code walking the stack
won't see any of the JITed ones. The same for address correlation
done from user space via reading /proc/kallsyms. This is read by
tools like perf, but the latter is also useful for permanent live
tracing with eBPF itself in combination with stack maps when other
eBPF types are part of the callchain. See offwaketime example on
dumping stack from a map.This work tries to tackle that issue by making the addresses and
symbols known to the kernel. The lookup from *kernel_text_address()
is implemented through a latched RB tree that can be read under
RCU in fast-path that is also shared for symbol/size/offset lookup
for a specific given address in kallsyms. The slow-path iteration
through all symbols in the seq file done via RCU list, which holds
a tiny fraction of all exported ksyms, usually below 0.1 percent.
Function symbols are exported as bpf_prog_, in order to aide
debugging and attribution. This facility is currently enabled for
root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening
is active in any mode. The rationale behind this is that still a lot
of systems ship with world read permissions on kallsyms thus addresses
should not get suddenly exposed for them. If that situation gets
much better in future, we always have the option to change the
default on this. Likewise, unprivileged programs are not allowed
to add entries there either, but that is less of a concern as most
such programs types relevant in this context are for root-only anyway.
If enabled, call graphs and stack traces will then show a correct
attribution; one example is illustrated below, where the trace is
now visible in tooling such as perf script --kallsyms=/proc/kallsyms
and friends.Before:
7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux)
f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so)After:
7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux)
[...]
7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux)
7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux)
f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so)Signed-off-by: Daniel Borkmann
Acked-by: Alexei Starovoitov
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller
16 Mar, 2016
1 commit
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Similar to how relative extables are implemented, it is possible to emit
the kallsyms table in such a way that it contains offsets relative to
some anchor point in the kernel image rather than absolute addresses.On 64-bit architectures, it cuts the size of the kallsyms address table
in half, since offsets between kernel symbols can typically be expressed
in 32 bits. This saves several hundreds of kilobytes of permanent
.rodata on average. In addition, the kallsyms address table is no
longer subject to dynamic relocation when CONFIG_RELOCATABLE is in
effect, so the relocation work done after decompression now doesn't have
to do relocation updates for all these values. This saves up to 24
bytes (i.e., the size of a ELF64 RELA relocation table entry) per value,
which easily adds up to a couple of megabytes of uncompressed __init
data on ppc64 or arm64. Even if these relocation entries typically
compress well, the combined size reduction of 2.8 MB uncompressed for a
ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500
KB space saving in the compressed image.Since it is useful for some architectures (like x86) to retain the
ability to emit absolute values as well, this patch also adds support
for capturing both absolute and relative values when
KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu
addresses as positive 32-bit values, and addresses relative to the
lowest encountered relative symbol as negative values, which are
subtracted from the runtime address of this base symbol to produce the
actual address.Support for the above is enabled by default for all architectures except
IA-64 and Tile-GX, whose symbols are too far apart to capture in this
manner.Signed-off-by: Ard Biesheuvel
Tested-by: Guenter Roeck
Reviewed-by: Kees Cook
Tested-by: Kees Cook
Cc: Heiko Carstens
Cc: Michael Ellerman
Cc: Ingo Molnar
Cc: H. Peter Anvin
Cc: Benjamin Herrenschmidt
Cc: Michal Marek
Cc: Rusty Russell
Cc: Arnd Bergmann
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
14 Oct, 2014
1 commit
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Reduce boilerplate code by using __seq_open_private() instead of
seq_open() in kallsyms_open().Signed-off-by: Rob Jones
Cc: Gideon Israel Dsouza
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Aug, 2014
1 commit
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__sprint_symbol() should restore original address when kallsyms_lookup()
failed to find a symbol. It's reported when dumpstack shows an address in
a dynamically allocated trampoline for ftrace.[ 1314.612287] [] dump_stack+0x45/0x56
[ 1314.612290] [] ? meminfo_proc_open+0x30/0x30
[ 1314.612293] [] kpatch_ftrace_handler+0x14/0xf0 [kpatch]
[ 1314.612306] [] 0xffffffffa00160c3You can see a difference in the hex address - c4 and c3. Fix it.
Signed-off-by: Namhyung Kim
Reported-by: Masami Hiramatsu
Cc: Steven Rostedt
Cc: Frederic Weisbecker
Cc: Josh Poimboeuf
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Apr, 2014
1 commit
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To increase compiler portability there is which
provides convenience macros for various gcc constructs. Eg: __weak for
__attribute__((weak)). I've replaced all instances of gcc attributes
with the right macro in the kernel subsystem.Signed-off-by: Gideon Israel Dsouza
Cc: "Rafael J. Wysocki"
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Apr, 2013
1 commit
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We don't export any symbols > 128 characters, but if we did then
kallsyms_expand_symbol() would overflow the buffer handed to it.
So we need check destination buffer length when copying.the related test:
if we define an EXPORT function which name more than 128.
will panic when call kallsyms_lookup_name by init_kprobes on booting.
after check the length (provide this patch), it is ok.Implementaion:
add additional destination buffer length parameter (maxlen)
if uncompressed string is too long (>= maxlen), it will be truncated.
not check the parameters whether valid, since it is a static function.Signed-off-by: Chen Gang
Signed-off-by: Rusty Russell
30 May, 2012
1 commit
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Using %ps in a printk format will sometimes fail silently and print the
empty string if the address passed in does not match a symbol that
kallsyms knows about. But using %pS will fall back to printing the full
address if kallsyms can't find the symbol. Make %ps act the same as %pS
by falling back to printing the address.While we're here also make %ps print the module that a symbol comes from
so that it matches what %pS already does. Take this simple function for
example (in a module):static void test_printk(void)
{
int test;
pr_info("with pS: %pS\n", &test);
pr_info("with ps: %ps\n", &test);
}Before this patch:
with pS: 0xdff7df44
with ps:After this patch:
with pS: 0xdff7df44
with ps: 0xdff7df44Signed-off-by: Stephen Boyd
Cc: Ingo Molnar
Cc: Peter Zijlstra
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
26 Mar, 2011
1 commit
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…/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
futex: Fix WARN_ON() test for UP
WARN_ON_SMP(): Allow use in if() statements on UP
x86, dumpstack: Use %pB format specifier for stack trace
vsprintf: Introduce %pB format specifier
lockdep: Remove unused 'factor' variable from lockdep_stats_show()
24 Mar, 2011
3 commits
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The %pB format specifier is for stack backtrace. Its handler
sprint_backtrace() does symbol lookup using (address-1) to
ensure the address will not point outside of the function.If there is a tail-call to the function marked "noreturn",
gcc optimized out the code after the call then causes saved
return address points outside of the function (i.e. the start
of the next function), so pollutes call trace somewhat.This patch adds the %pB printk mechanism that allows architecture
call-trace printout functions to improve backtrace printouts.Signed-off-by: Namhyung Kim
Acked-by: Steven Rostedt
Acked-by: Frederic Weisbecker
Cc: Linus Torvalds
Cc: Andrew Morton
Cc: linux-arch@vger.kernel.org
LKML-Reference:
Signed-off-by: Ingo Molnar -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
deal with races in /proc/*/{syscall,stack,personality}
proc: enable writing to /proc/pid/mem
proc: make check_mem_permission() return an mm_struct on success
proc: hold cred_guard_mutex in check_mem_permission()
proc: disable mem_write after exec
mm: implement access_remote_vm
mm: factor out main logic of access_process_vm
mm: use mm_struct to resolve gate vma's in __get_user_pages
mm: arch: rename in_gate_area_no_task to in_gate_area_no_mm
mm: arch: make in_gate_area take an mm_struct instead of a task_struct
mm: arch: make get_gate_vma take an mm_struct instead of a task_struct
x86: mark associated mm when running a task in 32 bit compatibility mode
x86: add context tag to mark mm when running a task in 32-bit compatibility mode
auxv: require the target to be tracable (or yourself)
close race in /proc/*/environ
report errors in /proc/*/*map* sanely
pagemap: close races with suid execve
make sessionid permissions in /proc/*/task/* match those in /proc/*
fix leaks in path_lookupat()Fix up trivial conflicts in fs/proc/base.c
-
Now that gate vma's are referenced with respect to a particular mm and not a
particular task it only makes sense to propagate the change to this predicate as
well.Signed-off-by: Stephen Wilson
Reviewed-by: Michel Lespinasse
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Signed-off-by: Al Viro
23 Mar, 2011
1 commit
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In an effort to reduce kernel address leaks that might be used to help
target kernel privilege escalation exploits, this patch uses %pK when
displaying addresses in /proc/kallsyms, /proc/modules, and
/sys/module/*/sections/*.Note that this changes %x to %p, so some legitimately 0 values in
/proc/kallsyms would have changed from 00000000 to "(null)". To avoid
this, "(null)" is not used when using the "K" format. Anything that was
already successfully parsing "(null)" in addition to full hex digits
should have no problem with this change. (Thanks to Joe Perches for the
suggestion.) Due to the %x to %p, "void *" casts are needed since these
addresses are already "unsigned long" everywhere internally, due to their
starting life as ELF section offsets.Signed-off-by: Kees Cook
Cc: Eugene Teo
Cc: Dan Rosenberg
Cc: Rusty Russell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
