Revision 14d6d86c210aea1a83c19a8f6391ecabcbefed94 authored by Alexei Starovoitov on 19 November 2020, 18:45:55 UTC, committed by Alexei Starovoitov on 19 November 2020, 19:58:15 UTC
Daniel Xu says:
====================
6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user,
kernel}_str helpers") introduced a subtle bug where
bpf_probe_read_user_str() would potentially copy a few extra bytes after
the NUL terminator.
This issue is particularly nefarious when strings are used as map keys,
as seemingly identical strings can occupy multiple entries in a map.
This patchset fixes the issue and introduces a selftest to prevent
future regressions.
v6 -> v7:
* Add comments
v5 -> v6:
* zero-pad up to sizeof(unsigned long) after NUL
v4 -> v5:
* don't read potentially uninitialized memory
v3 -> v4:
* directly pass userspace pointer to prog
* test more strings of different length
v2 -> v3:
* set pid filter before attaching prog in selftest
* use long instead of int as bpf_probe_read_user_str() retval
* style changes
v1 -> v2:
* add Fixes: tag
* add selftest
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| File | Mode | Size |
|---|---|---|
| bpf | ||
| cgroup | ||
| configs | ||
| debug | ||
| dma | ||
| entry | ||
| events | ||
| gcov | ||
| irq | ||
| kcsan | ||
| livepatch | ||
| locking | ||
| power | ||
| printk | ||
| rcu | ||
| sched | ||
| time | ||
| trace | ||
| .gitignore | -rw-r--r-- | 71 bytes |
| Kconfig.freezer | -rw-r--r-- | 92 bytes |
| Kconfig.hz | -rw-r--r-- | 1.7 KB |
| Kconfig.locks | -rw-r--r-- | 4.9 KB |
| Kconfig.preempt | -rw-r--r-- | 3.0 KB |
| Makefile | -rw-r--r-- | 4.8 KB |
| acct.c | -rw-r--r-- | 15.5 KB |
| async.c | -rw-r--r-- | 10.2 KB |
| audit.c | -rw-r--r-- | 63.4 KB |
| audit.h | -rw-r--r-- | 10.3 KB |
| audit_fsnotify.c | -rw-r--r-- | 5.2 KB |
| audit_tree.c | -rw-r--r-- | 25.6 KB |
| audit_watch.c | -rw-r--r-- | 13.7 KB |
| auditfilter.c | -rw-r--r-- | 34.1 KB |
| auditsc.c | -rw-r--r-- | 71.9 KB |
| backtracetest.c | -rw-r--r-- | 1.9 KB |
| bounds.c | -rw-r--r-- | 751 bytes |
| capability.c | -rw-r--r-- | 14.6 KB |
| compat.c | -rw-r--r-- | 7.3 KB |
| configs.c | -rw-r--r-- | 2.0 KB |
| context_tracking.c | -rw-r--r-- | 6.4 KB |
| cpu.c | -rw-r--r-- | 60.8 KB |
| cpu_pm.c | -rw-r--r-- | 5.4 KB |
| crash_core.c | -rw-r--r-- | 12.8 KB |
| crash_dump.c | -rw-r--r-- | 1.1 KB |
| cred.c | -rw-r--r-- | 23.3 KB |
| delayacct.c | -rw-r--r-- | 4.7 KB |
| dma.c | -rw-r--r-- | 3.3 KB |
| elfcore.c | -rw-r--r-- | 459 bytes |
| exec_domain.c | -rw-r--r-- | 1.1 KB |
| exit.c | -rw-r--r-- | 43.0 KB |
| extable.c | -rw-r--r-- | 4.4 KB |
| fail_function.c | -rw-r--r-- | 6.9 KB |
| fork.c | -rw-r--r-- | 74.1 KB |
| freezer.c | -rw-r--r-- | 4.4 KB |
| futex.c | -rw-r--r-- | 109.1 KB |
| gen_kheaders.sh | -rwxr-xr-x | 3.2 KB |
| groups.c | -rw-r--r-- | 4.9 KB |
| hung_task.c | -rw-r--r-- | 7.5 KB |
| iomem.c | -rw-r--r-- | 4.7 KB |
| irq_work.c | -rw-r--r-- | 4.8 KB |
| jump_label.c | -rw-r--r-- | 20.9 KB |
| kallsyms.c | -rw-r--r-- | 18.6 KB |
| kcmp.c | -rw-r--r-- | 5.7 KB |
| kcov.c | -rw-r--r-- | 27.7 KB |
| kexec.c | -rw-r--r-- | 8.0 KB |
| kexec_core.c | -rw-r--r-- | 31.2 KB |
| kexec_elf.c | -rw-r--r-- | 11.4 KB |
| kexec_file.c | -rw-r--r-- | 33.3 KB |
| kexec_internal.h | -rw-r--r-- | 976 bytes |
| kheaders.c | -rw-r--r-- | 1.6 KB |
| kmod.c | -rw-r--r-- | 5.0 KB |
| kprobes.c | -rw-r--r-- | 71.2 KB |
| ksysfs.c | -rw-r--r-- | 6.3 KB |
| kthread.c | -rw-r--r-- | 36.4 KB |
| latencytop.c | -rw-r--r-- | 7.2 KB |
| module-internal.h | -rw-r--r-- | 782 bytes |
| module.c | -rw-r--r-- | 117.8 KB |
| module_signature.c | -rw-r--r-- | 1.1 KB |
| module_signing.c | -rw-r--r-- | 1.1 KB |
| notifier.c | -rw-r--r-- | 16.3 KB |
| nsproxy.c | -rw-r--r-- | 12.9 KB |
| padata.c | -rw-r--r-- | 28.0 KB |
| panic.c | -rw-r--r-- | 18.3 KB |
| params.c | -rw-r--r-- | 22.8 KB |
| pid.c | -rw-r--r-- | 17.0 KB |
| pid_namespace.c | -rw-r--r-- | 11.3 KB |
| profile.c | -rw-r--r-- | 14.8 KB |
| ptrace.c | -rw-r--r-- | 36.5 KB |
| range.c | -rw-r--r-- | 3.0 KB |
| reboot.c | -rw-r--r-- | 14.1 KB |
| regset.c | -rw-r--r-- | 1.9 KB |
| relay.c | -rw-r--r-- | 32.1 KB |
| resource.c | -rw-r--r-- | 45.4 KB |
| rseq.c | -rw-r--r-- | 9.8 KB |
| scftorture.c | -rw-r--r-- | 16.9 KB |
| scs.c | -rw-r--r-- | 1.9 KB |
| seccomp.c | -rw-r--r-- | 54.2 KB |
| signal.c | -rw-r--r-- | 118.8 KB |
| smp.c | -rw-r--r-- | 26.7 KB |
| smpboot.c | -rw-r--r-- | 11.7 KB |
| smpboot.h | -rw-r--r-- | 640 bytes |
| softirq.c | -rw-r--r-- | 18.1 KB |
| stackleak.c | -rw-r--r-- | 3.6 KB |
| stacktrace.c | -rw-r--r-- | 9.6 KB |
| static_call.c | -rw-r--r-- | 10.6 KB |
| stop_machine.c | -rw-r--r-- | 17.2 KB |
| sys.c | -rw-r--r-- | 62.9 KB |
| sys_ni.c | -rw-r--r-- | 9.9 KB |
| sysctl-test.c | -rw-r--r-- | 10.8 KB |
| sysctl.c | -rw-r--r-- | 80.2 KB |
| task_work.c | -rw-r--r-- | 4.3 KB |
| taskstats.c | -rw-r--r-- | 15.2 KB |
| test_kprobes.c | -rw-r--r-- | 5.9 KB |
| torture.c | -rw-r--r-- | 21.7 KB |
| tracepoint.c | -rw-r--r-- | 15.6 KB |
| tsacct.c | -rw-r--r-- | 4.7 KB |
| ucount.c | -rw-r--r-- | 5.6 KB |
| uid16.c | -rw-r--r-- | 5.1 KB |
| uid16.h | -rw-r--r-- | 442 bytes |
| umh.c | -rw-r--r-- | 15.0 KB |
| up.c | -rw-r--r-- | 2.3 KB |
| user-return-notifier.c | -rw-r--r-- | 1.3 KB |
| user.c | -rw-r--r-- | 5.5 KB |
| user_namespace.c | -rw-r--r-- | 33.2 KB |
| usermode_driver.c | -rw-r--r-- | 4.1 KB |
| utsname.c | -rw-r--r-- | 3.8 KB |
| utsname_sysctl.c | -rw-r--r-- | 3.2 KB |
| watch_queue.c | -rw-r--r-- | 16.4 KB |
| watchdog.c | -rw-r--r-- | 20.1 KB |
| watchdog_hld.c | -rw-r--r-- | 7.7 KB |
| workqueue.c | -rw-r--r-- | 165.8 KB |
| workqueue_internal.h | -rw-r--r-- | 2.4 KB |
Computing file changes ...
