diff options
| author | Zheng Yejian <zhengyejian1@huawei.com> | 2022-11-14 18:46:32 +0800 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2022-11-17 20:41:01 -0500 |
| commit | 067df9e0ad48a97382ab2179bbe773a13a846028 (patch) | |
| tree | 698dee80b7f9beedcfdd3a77d3e824489cb31b04 /scripts/bpf_doc.py | |
| parent | b8752064e30697e3982418f4274cc63cfc6f3027 (diff) | |
tracing: Fix potential null-pointer-access of entry in list 'tr->err_log'
Entries in list 'tr->err_log' will be reused after entry number
exceed TRACING_LOG_ERRS_MAX.
The cmd string of the to be reused entry will be freed first then
allocated a new one. If the allocation failed, then the entry will
still be in list 'tr->err_log' but its 'cmd' field is set to be NULL,
later access of 'cmd' is risky.
Currently above problem can cause the loss of 'cmd' information of first
entry in 'tr->err_log'. When execute `cat /sys/kernel/tracing/error_log`,
reproduce logs like:
[ 37.495100] trace_kprobe: error: Maxactive is not for kprobe(null) ^
[ 38.412517] trace_kprobe: error: Maxactive is not for kprobe
Command: p4:myprobe2 do_sys_openat2
^
Link: https://lore.kernel.org/linux-trace-kernel/20221114104632.3547266-1-zhengyejian1@huawei.com
Fixes: 1581a884b7ca ("tracing: Remove size restriction on tracing_log_err cmd strings")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Diffstat (limited to 'scripts/bpf_doc.py')
0 files changed, 0 insertions, 0 deletions