public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: wuchi <wuchi.zero@gmail.com>
To: mhiramat@kernel.org, kafai@fb.com, songliubraving@fb.com,
	yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org
Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, bpf@vger.kernel.org
Subject: [PATCH] lib/error-inject: Traverse list with mutex
Date: Mon, 20 Jun 2022 18:02:44 +0800	[thread overview]
Message-ID: <20220620100244.82896-1-wuchi.zero@gmail.com> (raw)

Traversing list without mutex in get_injectable_error_type will
race with the following code:
    list_del_init(&ent->list)
    kfree(ent)
in module_unload_ei_list. So fix that.

Signed-off-by: wuchi <wuchi.zero@gmail.com>
---
 lib/error-inject.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/error-inject.c b/lib/error-inject.c
index 4a4f1278c419..1afca1b1cdea 100644
--- a/lib/error-inject.c
+++ b/lib/error-inject.c
@@ -40,12 +40,18 @@ bool within_error_injection_list(unsigned long addr)
 int get_injectable_error_type(unsigned long addr)
 {
 	struct ei_entry *ent;
+	int ei_type = EI_ETYPE_NONE;
 
+	mutex_lock(&ei_mutex);
 	list_for_each_entry(ent, &error_injection_list, list) {
-		if (addr >= ent->start_addr && addr < ent->end_addr)
-			return ent->etype;
+		if (addr >= ent->start_addr && addr < ent->end_addr) {
+			ei_type = ent->etype;
+			break;
+		}
 	}
-	return EI_ETYPE_NONE;
+	mutex_unlock(&ei_mutex);
+
+	return ei_type;
 }
 
 /*
-- 
2.20.1


                 reply	other threads:[~2022-06-20 10:03 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220620100244.82896-1-wuchi.zero@gmail.com \
    --to=wuchi.zero@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=bpf@vger.kernel.org \
    --cc=john.fastabend@gmail.com \
    --cc=kafai@fb.com \
    --cc=kpsingh@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mhiramat@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=songliubraving@fb.com \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox