10:47 a.m.
Hi Kees,
[FYI, it's a private test report for your RFC patch.]
[auto build test ERROR on tip/sched/core]
[also build test ERROR on kees/for-next/pstore linus/master v5.9-rc4]
[cannot apply to security/next-testing next-20200911]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url:
https://github.com/0day-ci/linux/commits/Kees-Cook/Fork-brute-force-attac...
base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
848785df48835eefebe0c4eb5da7690690b0a8b7
config: microblaze-randconfig-r033-20200911 (attached as .config)
compiler: microblaze-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=microblaze
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All errors (new ones prefixed by >>):
microblaze-linux-ld: security/fbfam/fbfam.o: in function `fbfam_handle_attack':
> security/fbfam/fbfam.c:206: undefined reference to
`__udivdi3'
# https://github.com/0day-ci/linux/commit/2a9c0b8f7327cdab5ef73c9a9a4447d25...
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review
Kees-Cook/Fork-brute-force-attack-mitigation-fbfam/20200911-042512
git checkout 2a9c0b8f7327cdab5ef73c9a9a4447d25c084bca
vim +206 security/fbfam/fbfam.c
176
177 /**
178 * fbfam_handle_attack() - Fork brute force attack detection.
179 * @signal: Signal number that causes the core dump.
180 *
181 * The crashing rate of an application is computed in milliseconds per fault in
182 * each crash. So, if this rate goes under a certain threshold there is a clear
183 * signal that the application is crashing quickly. At this moment, a fork brute
184 * force attack is happening.
185 *
186 * Return: -EFAULT if the current task doesn't have statistical data. Zero
187 * otherwise.
188 */
189 int fbfam_handle_attack(int signal)
190 {
191 struct fbfam_stats *stats = current->fbfam_stats;
192 u64 delta_jiffies, delta_time;
193 u64 crashing_rate;
194
195 if (!stats)
196 return -EFAULT;
197
198 if (!(signal == SIGILL || signal == SIGBUS || signal == SIGKILL ||
199 signal == SIGSEGV || signal == SIGSYS))
200 return 0;
201
202 stats->faults += 1;
203
204 delta_jiffies = get_jiffies_64() - stats->jiffies;
205 delta_time = jiffies64_to_msecs(delta_jiffies);
206 crashing_rate = delta_time / (u64)stats->faults;
207
208 if (crashing_rate < (u64)sysctl_crashing_rate_threshold)
209 pr_warn("fbfam: Fork brute force attack detected\n");
210
211 return 0;
212 }
213
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org