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Dario Petrillo adf791cf90 perf annotate: Avoid TUI crash when navigating in the annotation of recursive functions
commit d5962fb7d6 upstream.

In 'perf report', entering a recursive function from inside of itself
(either directly of indirectly through some other function) results in
calling symbol__annotate2 multiple() times, and freeing the whole
disassembly when exiting from the innermost instance.

The first issue causes the function's disassembly to be duplicated, and
the latter a heap use-after-free (and crash) when trying to access the
disassembly again.

I reproduced the bug on perf 5.11.22 (Ubuntu 20.04.3 LTS) and 5.16.rc8
with the following testcase (compile with gcc recursive.c -o recursive).
To reproduce:

- perf record ./recursive
- perf report
- enter fibonacci and annotate it
- move the cursor on one of the "callq fibonacci" instructions and press enter
  - at this point there will be two copies of the function in the disassembly
- go back by pressing q, and perf will crash

  #include <stdio.h>

  int fibonacci(int n)
  {
      if(n <= 2) return 1;
      return fibonacci(n-1) + fibonacci(n-2);
  }

  int main()
  {
      printf("%d\n", fibonacci(40));
  }

This patch addresses the issue by annotating a function and freeing the
associated memory on exit only if no annotation is already present, so
that a recursive function is only annotated on entry.

Signed-off-by: Dario Petrillo <dario.pk1@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@kernel.org
Link: http://lore.kernel.org/lkml/20220109234441.325106-1-dario.pk1@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-20 09:13:15 +01:00
arch KVM: s390: Clarify SIGP orders versus STOP/RESTART 2022-01-20 09:13:14 +01:00
block iocost: Fix divide-by-zero on donation from low hweight cgroup 2021-12-22 09:32:48 +01:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: pcrypt - Delay write to padata->info 2021-11-18 19:16:44 +01:00
Documentation Input: i8042 - add deferred probe support 2022-01-05 12:42:32 +01:00
drivers firmware: qemu_fw_cfg: fix kobject leak in probe error path 2022-01-20 09:13:15 +01:00
fs 9p: only copy valid iattrs in 9P2000.L setattr implementation 2022-01-20 09:13:14 +01:00
include perf: Protect perf_guest_cbs with RCU 2022-01-20 09:13:14 +01:00
init init: make unknown command line param message clearer 2021-11-18 19:17:11 +01:00
ipc shm: extend forced shm destroy to support objects from several IPC nses 2021-11-25 09:48:42 +01:00
kernel perf: Protect perf_guest_cbs with RCU 2022-01-20 09:13:14 +01:00
lib siphash: use _unaligned version by default 2021-12-08 09:04:47 +01:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()' 2022-01-05 12:42:39 +01:00
net can: isotp: convert struct tpcon::{idx,len} to unsigned int 2022-01-16 09:12:44 +01:00
samples ftrace/samples: Add missing prototypes direct functions 2022-01-11 15:35:13 +01:00
scripts recordmcount.pl: fix typo in s390 mcount regex 2022-01-05 12:42:33 +01:00
security selinux: initialize proto variable in selinux_ip_postroute_compat() 2022-01-05 12:42:34 +01:00
sound ALSA: hda: intel-sdw-acpi: go through HDAS ACPI at max depth of 2 2022-01-05 12:42:33 +01:00
tools perf annotate: Avoid TUI crash when navigating in the annotation of recursive functions 2022-01-20 09:13:15 +01:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: downgrade two BUG_ONs to WARN_ON_ONCE 2021-12-22 09:32:34 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS drm fixes for 5.15 final 2021-10-28 12:17:01 -07:00
Makefile Linux 5.15.15 2022-01-16 09:12:45 +01:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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Please read the Documentation/process/changes.rst file, as it contains the
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