From: "J. Bruce Fields" <bfields@fieldses.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Jane Chu <jane.chu@oracle.com>,
CHUCK_LEVER <chuck.lever@oracle.com>,
linux-nfs@vger.kernel.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: kernel panic in 5.3-rc5, nfsd_reply_cache_stats_show+0x11
Date: Wed, 21 Aug 2019 10:12:28 -0400 [thread overview]
Message-ID: <20190821141228.GA22104@fieldses.org> (raw)
In-Reply-To: <CAPcyv4iPuTpk9bifyX5yQxO8gT0fRhYXPrwk-obazWA=Dou3iQ@mail.gmail.com>
Probably just needs the following.
I've been slow to get some bugfixes upstream, sorry--I'll go send a pull
request now....
--b.
commit 78e70e780b28
Author: He Zhe <zhe.he@windriver.com>
Date: Tue Aug 6 17:41:04 2019 +0800
nfsd4: Fix kernel crash when reading proc file reply_cache_stats
reply_cache_stats uses wrong parameter as seq file private structure and
thus causes the following kernel crash when users read
/proc/fs/nfsd/reply_cache_stats
BUG: kernel NULL pointer dereference, address: 00000000000001f9
PGD 0 P4D 0
Oops: 0000 [#3] SMP PTI
CPU: 6 PID: 1502 Comm: cat Tainted: G D 5.3.0-rc3+ #1
Hardware name: Intel Corporation Broadwell Client platform/Basking Ridge, BIOS BDW-E2R1.86C.0118.R01.1503110618 03/11/2015
RIP: 0010:nfsd_reply_cache_stats_show+0x3b/0x2d0
Code: 41 54 49 89 f4 48 89 fe 48 c7 c7 b3 10 33 88 53 bb e8 03 00 00 e8 88 82 d1 ff bf 58 89 41 00 e8 eb c5 85 00 48 83 eb 01 75 f0 <41> 8b 94 24 f8 01 00 00 48 c7 c6 be 10 33 88 4c 89 ef bb e8 03 00
RSP: 0018:ffffaa520106fe08 EFLAGS: 00010246
RAX: 000000cfe1a77123 RBX: 0000000000000000 RCX: 0000000000291b46
RDX: 000000cf00000000 RSI: 0000000000000006 RDI: 0000000000291b28
RBP: ffffaa520106fe20 R08: 0000000000000006 R09: 000000cfe17e55dd
R10: ffffa424e47c0000 R11: 000000000000030b R12: 0000000000000001
R13: ffffa424e5697000 R14: 0000000000000001 R15: ffffa424e5697000
FS: 00007f805735f580(0000) GS:ffffa424f8f80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001f9 CR3: 00000000655ce005 CR4: 00000000003606e0
Call Trace:
seq_read+0x194/0x3e0
__vfs_read+0x1b/0x40
vfs_read+0x95/0x140
ksys_read+0x61/0xe0
__x64_sys_read+0x1a/0x20
do_syscall_64+0x4d/0x120
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f805728b861
Code: fe ff ff 50 48 8d 3d 86 b4 09 00 e8 79 e0 01 00 66 0f 1f 84 00 00 00 00 00 48 8d 05 d9 19 0d 00 8b 00 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 c3 66 0f 1f 44 00 00 48 83 ec 28 48 89 54
RSP: 002b:00007ffea1ce3c38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f805728b861
RDX: 0000000000020000 RSI: 00007f8057183000 RDI: 0000000000000003
RBP: 00007f8057183000 R08: 00007f8057182010 R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 0000559a60e8ff10
R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
Modules linked in:
CR2: 00000000000001f9
---[ end trace 01613595153f0cba ]---
RIP: 0010:nfsd_reply_cache_stats_show+0x3b/0x2d0
Code: 41 54 49 89 f4 48 89 fe 48 c7 c7 b3 10 33 88 53 bb e8 03 00 00 e8 88 82 d1 ff bf 58 89 41 00 e8 eb c5 85 00 48 83 eb 01 75 f0 <41> 8b 94 24 f8 01 00 00 48 c7 c6 be 10 33 88 4c 89 ef bb e8 03 00
RSP: 0018:ffffaa52004b3e08 EFLAGS: 00010246
RAX: 0000002bab45a7c6 RBX: 0000000000000000 RCX: 0000000000291b4c
RDX: 0000002b00000000 RSI: 0000000000000004 RDI: 0000000000291b28
RBP: ffffaa52004b3e20 R08: 0000000000000004 R09: 0000002bab1c8c7a
R10: ffffa424e5500000 R11: 00000000000002a9 R12: 0000000000000001
R13: ffffa424e4475000 R14: 0000000000000001 R15: ffffa424e4475000
FS: 00007f805735f580(0000) GS:ffffa424f8f80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001f9 CR3: 00000000655ce005 CR4: 00000000003606e0
Killed
Fixes: 3ba75830ce17 ("nfsd4: drc containerization")
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 26ad75ae2be0..96352ab7bd81 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -571,7 +571,7 @@ nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *data)
*/
static int nfsd_reply_cache_stats_show(struct seq_file *m, void *v)
{
- struct nfsd_net *nn = v;
+ struct nfsd_net *nn = m->private;
seq_printf(m, "max entries: %u\n", nn->max_drc_entries);
seq_printf(m, "num entries: %u\n",
next prev parent reply other threads:[~2019-08-21 14:12 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-21 1:39 kernel panic in 5.3-rc5, nfsd_reply_cache_stats_show+0x11 jane.chu
2019-08-21 3:48 ` Dan Williams
2019-08-21 14:12 ` J. Bruce Fields [this message]
2019-08-21 21:28 ` jane.chu
2019-08-21 18:11 ` jane.chu
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=20190821141228.GA22104@fieldses.org \
--to=bfields@fieldses.org \
--cc=chuck.lever@oracle.com \
--cc=dan.j.williams@intel.com \
--cc=jane.chu@oracle.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nfs@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).