[PATCH 4/7] fs/binfmt_elf: use get_task_comm instead of open-coded string copy
From: Yafang Shao <hidden>
Date: 2021-11-08 08:39:55
Also in:
bpf, linux-fsdevel, linux-mm, lkml, netdev
Subsystem:
exec & binfmt api, elf, filesystems (vfs and infrastructure), the rest · Maintainers:
Kees Cook, Alexander Viro, Christian Brauner, Linus Torvalds
It is better to use get_task_comm() instead of the open coded string
copy as we do in other places.
struct elf_prpsinfo is used to dump the task information in userspace
coredump or kernel vmcore. Below is the verfication of vmcore,
crash> ps
PID PPID CPU TASK ST %MEM VSZ RSS COMM
0 0 0 ffffffff9d21a940 RU 0.0 0 0 [swapper/0] 0 0 1 ffffa09e40f85e80 RU 0.0 0 0 [swapper/1]
0 0 2 ffffa09e40f81f80 RU 0.0 0 0 [swapper/2]
0 0 3 ffffa09e40f83f00 RU 0.0 0 0 [swapper/3]
0 0 4 ffffa09e40f80000 RU 0.0 0 0 [swapper/4]
0 0 5 ffffa09e40f89f80 RU 0.0 0 0 [swapper/5]0 0 6 ffffa09e40f8bf00 RU 0.0 0 0 [swapper/6]
0 0 7 ffffa09e40f88000 RU 0.0 0 0 [swapper/7]
0 0 8 ffffa09e40f8de80 RU 0.0 0 0 [swapper/8]
0 0 9 ffffa09e40f95e80 RU 0.0 0 0 [swapper/9]
0 0 10 ffffa09e40f91f80 RU 0.0 0 0 [swapper/10]
0 0 11 ffffa09e40f93f00 RU 0.0 0 0 [swapper/11]
0 0 12 ffffa09e40f90000 RU 0.0 0 0 [swapper/12]
0 0 13 ffffa09e40f9bf00 RU 0.0 0 0 [swapper/13]
0 0 14 ffffa09e40f98000 RU 0.0 0 0 [swapper/14]
0 0 15 ffffa09e40f9de80 RU 0.0 0 0 [swapper/15]It works well as expected. Suggested-by: Kees Cook <redacted> Signed-off-by: Yafang Shao <redacted> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Arnaldo Carvalho de Melo <redacted> Cc: Andrii Nakryiko <redacted> Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Hildenbrand <redacted> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <redacted> Cc: Petr Mladek <pmladek@suse.com> --- fs/binfmt_elf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index a813b70f594e..138956fd4a88 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c@@ -1572,7 +1572,7 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p, SET_UID(psinfo->pr_uid, from_kuid_munged(cred->user_ns, cred->uid)); SET_GID(psinfo->pr_gid, from_kgid_munged(cred->user_ns, cred->gid)); rcu_read_unlock(); - strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname)); + get_task_comm(psinfo->pr_fname, p); return 0; }
--
2.17.1