The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
Possible dependencies:
4313e5a61304 ("tracing: Free buffers when a used dynamic event is removed")
5448d44c3855 ("tracing: Add unified dynamic event framework")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4313e5a613049dfc1819a6dfb5f94cf2caff9452 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Google)" <rostedt(a)goodmis.org>
Date: Wed, 23 Nov 2022 17:14:34 -0500
Subject: [PATCH] tracing: Free buffers when a used dynamic event is removed
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
After 65536 dynamic events have been added and removed, the "type" field
of the event then uses the first type number that is available (not
currently used by other events). A type number is the identifier of the
binary blobs in the tracing ring buffer (known as events) to map them to
logic that can parse the binary blob.
The issue is that if a dynamic event (like a kprobe event) is traced and
is in the ring buffer, and then that event is removed (because it is
dynamic, which means it can be created and destroyed), if another dynamic
event is created that has the same number that new event's logic on
parsing the binary blob will be used.
To show how this can be an issue, the following can crash the kernel:
# cd /sys/kernel/tracing
# for i in `seq 65536`; do
echo 'p:kprobes/foo do_sys_openat2 $arg1:u32' > kprobe_events
# done
For every iteration of the above, the writing to the kprobe_events will
remove the old event and create a new one (with the same format) and
increase the type number to the next available on until the type number
reaches over 65535 which is the max number for the 16 bit type. After it
reaches that number, the logic to allocate a new number simply looks for
the next available number. When an dynamic event is removed, that number
is then available to be reused by the next dynamic event created. That is,
once the above reaches the max number, the number assigned to the event in
that loop will remain the same.
Now that means deleting one dynamic event and created another will reuse
the previous events type number. This is where bad things can happen.
After the above loop finishes, the kprobes/foo event which reads the
do_sys_openat2 function call's first parameter as an integer.
# echo 1 > kprobes/foo/enable
# cat /etc/passwd > /dev/null
# cat trace
cat-2211 [005] .... 2007.849603: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
cat-2211 [005] .... 2007.849620: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
cat-2211 [005] .... 2007.849838: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
cat-2211 [005] .... 2007.849880: foo: (do_sys_openat2+0x0/0x130) arg1=4294967196
# echo 0 > kprobes/foo/enable
Now if we delete the kprobe and create a new one that reads a string:
# echo 'p:kprobes/foo do_sys_openat2 +0($arg2):string' > kprobe_events
And now we can the trace:
# cat trace
sendmail-1942 [002] ..... 530.136320: foo: (do_sys_openat2+0x0/0x240) arg1= cat-2046 [004] ..... 530.930817: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
cat-2046 [004] ..... 530.930961: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
cat-2046 [004] ..... 530.934278: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
cat-2046 [004] ..... 530.934563: foo: (do_sys_openat2+0x0/0x240) arg1="������������������������������������������������������������������������������������������������"
bash-1515 [007] ..... 534.299093: foo: (do_sys_openat2+0x0/0x240) arg1="kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk���������@��4Z����;Y�����U
And dmesg has:
==================================================================
BUG: KASAN: use-after-free in string+0xd4/0x1c0
Read of size 1 at addr ffff88805fdbbfa0 by task cat/2049
CPU: 0 PID: 2049 Comm: cat Not tainted 6.1.0-rc6-test+ #641
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
Call Trace:
<TASK>
dump_stack_lvl+0x5b/0x77
print_report+0x17f/0x47b
kasan_report+0xad/0x130
string+0xd4/0x1c0
vsnprintf+0x500/0x840
seq_buf_vprintf+0x62/0xc0
trace_seq_printf+0x10e/0x1e0
print_type_string+0x90/0xa0
print_kprobe_event+0x16b/0x290
print_trace_line+0x451/0x8e0
s_show+0x72/0x1f0
seq_read_iter+0x58e/0x750
seq_read+0x115/0x160
vfs_read+0x11d/0x460
ksys_read+0xa9/0x130
do_syscall_64+0x3a/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fc2e972ade2
Code: c0 e9 b2 fe ff ff 50 48 8d 3d b2 3f 0a 00 e8 05 f0 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24
RSP: 002b:00007ffc64e687c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007fc2e972ade2
RDX: 0000000000020000 RSI: 00007fc2e980d000 RDI: 0000000000000003
RBP: 00007fc2e980d000 R08: 00007fc2e980c010 R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000020f00
R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
</TASK>
The buggy address belongs to the physical page:
page:ffffea00017f6ec0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5fdbb
flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc0000000 0000000000000000 ffffea00017f6ec8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88805fdbbe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88805fdbbf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88805fdbbf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88805fdbc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88805fdbc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
This was found when Zheng Yejian sent a patch to convert the event type
number assignment to use IDA, which gives the next available number, and
this bug showed up in the fuzz testing by Yujie Liu and the kernel test
robot. But after further analysis, I found that this behavior is the same
as when the event type numbers go past the 16bit max (and the above shows
that).
As modules have a similar issue, but is dealt with by setting a
"WAS_ENABLED" flag when a module event is enabled, and when the module is
freed, if any of its events were enabled, the ring buffer that holds that
event is also cleared, to prevent reading stale events. The same can be
done for dynamic events.
If any dynamic event that is being removed was enabled, then make sure the
buffers they were enabled in are now cleared.
Link: https://lkml.kernel.org/r/20221123171434.545706e3@gandalf.local.home
Link: https://lore.kernel.org/all/20221110020319.1259291-1-zhengyejian1@huawei.co…
Cc: stable(a)vger.kernel.org
Cc: Andrew Morton <akpm(a)linux-foundation.org>
Depends-on: e18eb8783ec49 ("tracing: Add tracing_reset_all_online_cpus_unlocked() function")
Depends-on: 5448d44c38557 ("tracing: Add unified dynamic event framework")
Depends-on: 6212dd29683ee ("tracing/kprobes: Use dyn_event framework for kprobe events")
Depends-on: 065e63f951432 ("tracing: Only have rmmod clear buffers that its events were active in")
Depends-on: 575380da8b469 ("tracing: Only clear trace buffer on module unload if event was traced")
Fixes: 77b44d1b7c283 ("tracing/kprobes: Rename Kprobe-tracer to kprobe-event")
Reported-by: Zheng Yejian <zhengyejian1(a)huawei.com>
Reported-by: Yujie Liu <yujie.liu(a)intel.com>
Reported-by: kernel test robot <yujie.liu(a)intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat(a)kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org>
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index 154996684fb5..4376887e0d8a 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -118,6 +118,7 @@ int dyn_event_release(const char *raw_command, struct dyn_event_operations *type
if (ret)
break;
}
+ tracing_reset_all_online_cpus();
mutex_unlock(&event_mutex);
out:
argv_free(argv);
@@ -214,6 +215,7 @@ int dyn_events_release_all(struct dyn_event_operations *type)
break;
}
out:
+ tracing_reset_all_online_cpus();
mutex_unlock(&event_mutex);
return ret;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 78cd19e31dba..f71ea6e79b3c 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2880,7 +2880,10 @@ static int probe_remove_event_call(struct trace_event_call *call)
* TRACE_REG_UNREGISTER.
*/
if (file->flags & EVENT_FILE_FL_ENABLED)
- return -EBUSY;
+ goto busy;
+
+ if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+ tr->clear_trace = true;
/*
* The do_for_each_event_file_safe() is
* a double loop. After finding the call for this
@@ -2893,6 +2896,12 @@ static int probe_remove_event_call(struct trace_event_call *call)
__trace_remove_event_call(call);
return 0;
+ busy:
+ /* No need to clear the trace now */
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ tr->clear_trace = false;
+ }
+ return -EBUSY;
}
/* Remove an event_call */
Patch 1 fixes a possible deadlock in subflow_error_report() reported by
lockdep. The report was in fact a false positive but the modification
makes sense and silences lockdep to allow syzkaller to find real issues.
The regression has been introduced in v5.12.
Patch 2 is a refactoring needed to be able to fix the two next issues.
It improves the situation and can be backported up to v6.0.
Patches 3 and 4 fix UaF reported by KASAN. It fixes issues potentially
visible since v5.7 and v5.19 but only reproducible until recently
(v6.0). These two patches depend on patch 2/7.
Patch 5 fixes the order of the printed values: expected vs seen values.
The regression has been introduced recently: v6.3-rc1.
Patch 6 adds missing ro_after_init flags. A previous patch added them
for other functions but these two have been missed. This previous patch
has been backported to stable versions (up to v5.12) so probably better
to do the same here.
Patch 7 fixes tcp_set_state() being called twice in a row since v5.10.
Patch 8 fixes another lockdep false positive issue but this time in
MPTCP PM code. Same here, some modifications in the code has been made
to silence this issue and help finding real ones later. This issue can
be seen since v6.2.
Note that checkpatch.pl is now complaining about the "Closes" tag but
discussions are ongoing to add an exception:
https://lore.kernel.org/all/a27480c5-c3d4-b302-285e-323df0349b8f@tessares.n…
Signed-off-by: Matthieu Baerts <matthieu.baerts(a)tessares.net>
---
Changes in v2:
- Patches 3 and 4 have been modified to fix the issue reported on netdev
- Patch 8 has been added
- Rebased
- Link to v1: https://lore.kernel.org/r/20230227-upstream-net-20230227-mptcp-fixes-v1-0-0…
---
Geliang Tang (1):
mptcp: add ro_after_init for tcp{,v6}_prot_override
Matthieu Baerts (2):
selftests: mptcp: userspace pm: fix printed values
mptcp: avoid setting TCP_CLOSE state twice
Paolo Abeni (5):
mptcp: fix possible deadlock in subflow_error_report
mptcp: refactor passive socket initialization
mptcp: use the workqueue to destroy unaccepted sockets
mptcp: fix UaF in listener shutdown
mptcp: fix lockdep false positive in mptcp_pm_nl_create_listen_socket()
net/mptcp/pm_netlink.c | 16 +++
net/mptcp/protocol.c | 64 +++++------
net/mptcp/protocol.h | 6 +-
net/mptcp/subflow.c | 128 +++++++---------------
tools/testing/selftests/net/mptcp/userspace_pm.sh | 2 +-
5 files changed, 95 insertions(+), 121 deletions(-)
---
base-commit: 67eeadf2f95326f6344adacb70c880bf2ccff57b
change-id: 20230227-upstream-net-20230227-mptcp-fixes-cc78f3a2f5b2
Best regards,
--
Matthieu Baerts <matthieu.baerts(a)tessares.net>
According to the TJA1103 user manual, the bit for the reversed role in MII
or RMII modes is bit 4.
Cc: <stable(a)vger.kernel.org> # 5.15+
Signed-off-by: Radu Pirea (OSS) <radu-nicolae.pirea(a)oss.nxp.com>
---
drivers/net/phy/nxp-c45-tja11xx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/phy/nxp-c45-tja11xx.c b/drivers/net/phy/nxp-c45-tja11xx.c
index 047c581457e3..5813b07242ce 100644
--- a/drivers/net/phy/nxp-c45-tja11xx.c
+++ b/drivers/net/phy/nxp-c45-tja11xx.c
@@ -79,7 +79,7 @@
#define SGMII_ABILITY BIT(0)
#define VEND1_MII_BASIC_CONFIG 0xAFC6
-#define MII_BASIC_CONFIG_REV BIT(8)
+#define MII_BASIC_CONFIG_REV BIT(4)
#define MII_BASIC_CONFIG_SGMII 0x9
#define MII_BASIC_CONFIG_RGMII 0x7
#define MII_BASIC_CONFIG_RMII 0x5
--
2.34.1