| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20240904174339.7790-1-kuniyu@amazon.com>
Date: Wed, 4 Sep 2024 10:43:39 -0700
From: Kuniyuki Iwashima <kuniyu@...zon.com>
To: <syzbot+0532ac7a06fb1a03187e@...kaller.appspotmail.com>
CC: <davem@...emloft.net>, <edumazet@...gle.com>, <horms@...nel.org>,
<kuba@...nel.org>, <kuniyu@...zon.com>, <linux-can@...r.kernel.org>,
<linux-kernel@...r.kernel.org>, <mkl@...gutronix.de>,
<netdev@...r.kernel.org>, <pabeni@...hat.com>, <socketcan@...tkopp.net>,
<syzkaller-bugs@...glegroups.com>
Subject: Re: [syzbot] [can?] WARNING in remove_proc_entry (6)
From: syzbot <syzbot+0532ac7a06fb1a03187e@...kaller.appspotmail.com>
Date: Wed, 04 Sep 2024 06:56:23 -0700
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 5517ae241919 Merge tag 'for-net-2024-08-30' of git://git.k..
> git tree: net
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=111adcfb980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=996585887acdadb3
> dashboard link: https://syzkaller.appspot.com/bug?extid=0532ac7a06fb1a03187e
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=138d43db980000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11fe3d43980000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/ddded5c54678/disk-5517ae24.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/ce0dfe9dbb55/vmlinux-5517ae24.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/ca81d6e3361d/bzImage-5517ae24.xz
>
> The issue was bisected to:
>
> commit 76fe372ccb81b0c89b6cd2fec26e2f38c958be85
> Author: Kuniyuki Iwashima <kuniyu@...zon.com>
> Date: Mon Jul 22 19:28:42 2024 +0000
>
> can: bcm: Remove proc entry when dev is unregistered.
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=116f8e8f980000
> final oops: https://syzkaller.appspot.com/x/report.txt?x=136f8e8f980000
> console output: https://syzkaller.appspot.com/x/log.txt?x=156f8e8f980000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+0532ac7a06fb1a03187e@...kaller.appspotmail.com
> Fixes: 76fe372ccb81 ("can: bcm: Remove proc entry when dev is unregistered.")
>
> ------------[ cut here ]------------
> name '4986'
> WARNING: CPU: 0 PID: 5234 at fs/proc/generic.c:711 remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
> Modules linked in:
> CPU: 0 UID: 0 PID: 5234 Comm: syz-executor606 Not tainted 6.11.0-rc5-syzkaller-00178-g5517ae241919 #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
> RIP: 0010:remove_proc_entry+0x2e7/0x5d0 fs/proc/generic.c:711
> Code: ff eb 05 e8 cb 1e 5e ff 48 8b 5c 24 10 48 c7 c7 e0 f7 aa 8e e8 2a 38 8e 09 90 48 c7 c7 60 3a 1b 8c 48 89 de e8 da 42 20 ff 90 <0f> 0b 90 90 48 8b 44 24 18 48 c7 44 24 40 0e 36 e0 45 49 c7 04 07
> RSP: 0018:ffffc9000345fa20 EFLAGS: 00010246
> RAX: 2a2d0aee2eb64600 RBX: ffff888032f1f548 RCX: ffff888029431e00
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> RBP: ffffc9000345fb08 R08: ffffffff8155b2f2 R09: 1ffff1101710519a
> R10: dffffc0000000000 R11: ffffed101710519b R12: ffff888011d38640
> R13: 0000000000000004 R14: 0000000000000000 R15: dffffc0000000000
> FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007fcfb52722f0 CR3: 000000000e734000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> bcm_release+0x250/0x880 net/can/bcm.c:1578
> __sock_release net/socket.c:659 [inline]
> sock_close+0xbc/0x240 net/socket.c:1421
> __fput+0x24a/0x8a0 fs/file_table.c:422
> task_work_run+0x24f/0x310 kernel/task_work.c:228
> exit_task_work include/linux/task_work.h:40 [inline]
> do_exit+0xa2f/0x27f0 kernel/exit.c:882
> do_group_exit+0x207/0x2c0 kernel/exit.c:1031
> __do_sys_exit_group kernel/exit.c:1042 [inline]
> __se_sys_exit_group kernel/exit.c:1040 [inline]
> __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040
> x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7fcfb51ee969
> Code: Unable to access opcode bytes at 0x7fcfb51ee93f.
> RSP: 002b:00007ffce0109ca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
> RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fcfb51ee969
> RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
> RBP: 00007fcfb526f3b0 R08: ffffffffffffffb8 R09: 0000555500000000
> R10: 0000555500000000 R11: 0000000000000246 R12: 00007fcfb526f3b0
> R13: 0000000000000000 R14: 00007fcfb5271ee0 R15: 00007fcfb51bf160
> </TASK>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@...glegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
Ugh, I forgot to clear bo->bcm_proc_read.
#syz test git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git HEAD
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 46d3ec3aa44b..217049fa496e 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -1471,8 +1471,10 @@ static void bcm_notify(struct bcm_sock *bo, unsigned long msg,
/* remove device reference, if this is our bound device */
if (bo->bound && bo->ifindex == dev->ifindex) {
#if IS_ENABLED(CONFIG_PROC_FS)
- if (sock_net(sk)->can.bcmproc_dir && bo->bcm_proc_read)
+ if (sock_net(sk)->can.bcmproc_dir && bo->bcm_proc_read) {
remove_proc_entry(bo->procname, sock_net(sk)->can.bcmproc_dir);
+ bo->bcm_proc_read = NULL;
+ }
#endif
bo->bound = 0;
bo->ifindex = 0;
Powered by blists - more mailing lists