2019-08-02 02:58:29

by syzbot

[permalink] [raw]
Subject: memory leak in tipc_group_create_member

Hello,

syzbot found the following crash on:

HEAD commit: a9815a4f Merge branch 'x86-urgent-for-linus' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a6dbf0600000
kernel config: https://syzkaller.appspot.com/x/.config?x=37c48fb52e3789e6
dashboard link: https://syzkaller.appspot.com/bug?extid=f95d90c454864b3b5bc9
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13be3ecc600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11c992b4600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]

executing program
BUG: memory leak
unreferenced object 0xffff888122bca200 (size 128):
comm "syz-executor232", pid 7065, jiffies 4294943817 (age 8.880s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 18 a2 bc 22 81 88 ff ff ..........."....
backtrace:
[<000000005bada299>] kmemleak_alloc_recursive
include/linux/kmemleak.h:43 [inline]
[<000000005bada299>] slab_post_alloc_hook mm/slab.h:522 [inline]
[<000000005bada299>] slab_alloc mm/slab.c:3319 [inline]
[<000000005bada299>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
[<00000000e7bcdc9f>] kmalloc include/linux/slab.h:552 [inline]
[<00000000e7bcdc9f>] kzalloc include/linux/slab.h:748 [inline]
[<00000000e7bcdc9f>] tipc_group_create_member+0x3c/0x190
net/tipc/group.c:306
[<0000000005f56f40>] tipc_group_add_member+0x34/0x40
net/tipc/group.c:327
[<0000000044406683>] tipc_nametbl_build_group+0x9b/0xf0
net/tipc/name_table.c:600
[<000000009f71e803>] tipc_sk_join net/tipc/socket.c:2901 [inline]
[<000000009f71e803>] tipc_setsockopt+0x170/0x490 net/tipc/socket.c:3006
[<000000007f61cbc2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084
[<00000000cc630372>] __do_sys_setsockopt net/socket.c:2100 [inline]
[<00000000cc630372>] __se_sys_setsockopt net/socket.c:2097 [inline]
[<00000000cc630372>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097
[<00000000ec30be33>] do_syscall_64+0x76/0x1a0
arch/x86/entry/common.c:296
[<00000000271be3e6>] entry_SYSCALL_64_after_hwframe+0x44/0xa9



---
This bug 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 [email protected].

syzbot will keep track of this bug report. See:
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syzbot can test patches for this bug, for details see:
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2019-08-03 04:28:14

by Ying Xue

[permalink] [raw]
Subject: Re: memory leak in tipc_group_create_member

On 8/2/19 3:44 PM, Hillf Danton wrote:
>
> On Thu, 01 Aug 2019 19:38:06 -0700
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit: a9815a4f Merge branch 'x86-urgent-for-linus' of git://git...
>> git tree: upstream
>> console output: https://syzkaller.appspot.com/x/log.txt?x=12a6dbf0600000
>> kernel config: https://syzkaller.appspot.com/x/.config?x=37c48fb52e3789e6
>> dashboard link: https://syzkaller.appspot.com/bug?extid=f95d90c454864b3b5bc9
>> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13be3ecc600000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11c992b4600000
>>
>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>> Reported-by: [email protected]
>>
>> executing program
>> BUG: memory leak
>> unreferenced object 0xffff888122bca200 (size 128):
>> comm "syz-executor232", pid 7065, jiffies 4294943817 (age 8.880s)
>> hex dump (first 32 bytes):
>> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>> 00 00 00 00 00 00 00 00 18 a2 bc 22 81 88 ff ff ..........."....
>> backtrace:
>> [<000000005bada299>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
>> [<000000005bada299>] slab_post_alloc_hook mm/slab.h:522 [inline]
>> [<000000005bada299>] slab_alloc mm/slab.c:3319 [inline]
>> [<000000005bada299>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548
>> [<00000000e7bcdc9f>] kmalloc include/linux/slab.h:552 [inline]
>> [<00000000e7bcdc9f>] kzalloc include/linux/slab.h:748 [inline]
>> [<00000000e7bcdc9f>] tipc_group_create_member+0x3c/0x190 net/tipc/group.c:306
>> [<0000000005f56f40>] tipc_group_add_member+0x34/0x40 net/tipc/group.c:327
>> [<0000000044406683>] tipc_nametbl_build_group+0x9b/0xf0 net/tipc/name_table.c:600
>> [<000000009f71e803>] tipc_sk_join net/tipc/socket.c:2901 [inline]
>> [<000000009f71e803>] tipc_setsockopt+0x170/0x490 net/tipc/socket.c:3006
>> [<000000007f61cbc2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084
>> [<00000000cc630372>] __do_sys_setsockopt net/socket.c:2100 [inline]
>> [<00000000cc630372>] __se_sys_setsockopt net/socket.c:2097 [inline]
>> [<00000000cc630372>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097
>> [<00000000ec30be33>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296
>> [<00000000271be3e6>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
>>

Acked-by: Ying Xue <[email protected]>

>
> --- a/net/tipc/group.c
> +++ b/net/tipc/group.c
> @@ -273,7 +273,7 @@ static struct tipc_member *tipc_group_fi
> return NULL;
> }
>
> -static void tipc_group_add_to_tree(struct tipc_group *grp,
> +static struct tipc_member *tipc_group_add_to_tree(struct tipc_group *grp,
> struct tipc_member *m)
> {
> u64 nkey, key = (u64)m->node << 32 | m->port;
> @@ -282,7 +282,6 @@ static void tipc_group_add_to_tree(struc
>
> n = &grp->members.rb_node;
> while (*n) {
> - tmp = container_of(*n, struct tipc_member, tree_node);
> parent = *n;
> tmp = container_of(parent, struct tipc_member, tree_node);
> nkey = (u64)tmp->node << 32 | tmp->port;
> @@ -291,17 +290,18 @@ static void tipc_group_add_to_tree(struc
> else if (key > nkey)
> n = &(*n)->rb_right;
> else
> - return;
> + return tmp;
> }
> rb_link_node(&m->tree_node, parent, n);
> rb_insert_color(&m->tree_node, &grp->members);
> + return m;
> }
>
> static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
> u32 node, u32 port,
> u32 instance, int state)
> {
> - struct tipc_member *m;
> + struct tipc_member *m, *n;
>
> m = kzalloc(sizeof(*m), GFP_ATOMIC);
> if (!m)
> @@ -315,10 +315,14 @@ static struct tipc_member *tipc_group_cr
> m->instance = instance;
> m->bc_acked = grp->bc_snd_nxt - 1;
> grp->member_cnt++;
> - tipc_group_add_to_tree(grp, m);
> - tipc_nlist_add(&grp->dests, m->node);
> - m->state = state;
> - return m;
> + n = tipc_group_add_to_tree(grp, m);
> + if (n == m) {
> + tipc_nlist_add(&grp->dests, m->node);
> + m->state = state;
> + } else {
> + kfree(m);
> + }
> + return n;
> }
>
> void tipc_group_add_member(struct tipc_group *grp, u32 node,
> --
>
>

2020-09-12 10:27:19

by Peilin Ye

[permalink] [raw]
Subject: [Linux-kernel-mentees] [PATCH net] tipc: Fix memory leak in tipc_group_create_member()

tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an
existing node, causing tipc_group_create_member() to leak memory. Let
tipc_group_add_to_tree() return an error in such a case, so that
tipc_group_create_member() can handle it properly.

Fixes: 75da2163dbb6 ("tipc: introduce communication groups")
Reported-and-tested-by: [email protected]
Cc: Hillf Danton <[email protected]>
Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13aff
Signed-off-by: Peilin Ye <[email protected]>
---
Decoded syzbot reproducer in pseudo-C:

fd0 = socket(AF_TIPC, SOCK_DGRAM, 0);

sockaddr_tipc.family = AF_TIPC;
sockaddr_tipc.addrtype = TIPC_ADDR_NAMESEQ;
sockaddr_tipc.scope = 0;
sockaddr_tipc.addr.namesq.type = TIPC_RESERVED_TYPES + 1;
bind(fd0, &sockaddr_tipc, sizeof(sockaddr_tipc));

tipc_group_req0.type = TIPC_RESERVED_TYPES + 1;
setsockopt(fd0, SOL_TIPC, TIPC_GROUP_JOIN, &tipc_group_req0, sizeof(tipc_group_req0));

fd1 = socket(AF_TIPC, SOCK_STREAM, 0);

tipc_group_req1.type = TIPC_RESERVED_TYPES + 1;
tipc_group_req1.scope = TIPC_CLUSTER_SCOPE;
setsockopt(fd1, SOL_TIPC, TIPC_GROUP_JOIN, &tipc_group_req1, sizeof(tipc_group_req1));

net/tipc/group.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/tipc/group.c b/net/tipc/group.c
index 588c2d2b0c69..553cf08b4d76 100644
--- a/net/tipc/group.c
+++ b/net/tipc/group.c
@@ -273,8 +273,8 @@ static struct tipc_member *tipc_group_find_node(struct tipc_group *grp,
return NULL;
}

-static void tipc_group_add_to_tree(struct tipc_group *grp,
- struct tipc_member *m)
+static int tipc_group_add_to_tree(struct tipc_group *grp,
+ struct tipc_member *m)
{
u64 nkey, key = (u64)m->node << 32 | m->port;
struct rb_node **n, *parent = NULL;
@@ -291,10 +291,11 @@ static void tipc_group_add_to_tree(struct tipc_group *grp,
else if (key > nkey)
n = &(*n)->rb_right;
else
- return;
+ return -1;
}
rb_link_node(&m->tree_node, parent, n);
rb_insert_color(&m->tree_node, &grp->members);
+ return 0;
}

static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
@@ -302,6 +303,7 @@ static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
u32 instance, int state)
{
struct tipc_member *m;
+ int ret;

m = kzalloc(sizeof(*m), GFP_ATOMIC);
if (!m)
@@ -314,8 +316,12 @@ static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
m->port = port;
m->instance = instance;
m->bc_acked = grp->bc_snd_nxt - 1;
+ ret = tipc_group_add_to_tree(grp, m);
+ if (ret < 0) {
+ kfree(m);
+ return NULL;
+ }
grp->member_cnt++;
- tipc_group_add_to_tree(grp, m);
tipc_nlist_add(&grp->dests, m->node);
m->state = state;
return m;
--
2.25.1

2020-09-13 01:27:19

by David Miller

[permalink] [raw]
Subject: Re: [Linux-kernel-mentees] [PATCH net] tipc: Fix memory leak in tipc_group_create_member()

From: Peilin Ye <[email protected]>
Date: Sat, 12 Sep 2020 06:22:30 -0400

> @@ -291,10 +291,11 @@ static void tipc_group_add_to_tree(struct tipc_group *grp,
> else if (key > nkey)
> n = &(*n)->rb_right;
> else
> - return;
> + return -1;

Use a real error code like "-EEXIST", thank you.

2020-09-13 07:51:36

by Peilin Ye

[permalink] [raw]
Subject: Re: [Linux-kernel-mentees] [PATCH net] tipc: Fix memory leak in tipc_group_create_member()

On Sat, Sep 12, 2020 at 06:23:36PM -0700, David Miller wrote:
> From: Peilin Ye <[email protected]>
> Date: Sat, 12 Sep 2020 06:22:30 -0400
>
> > @@ -291,10 +291,11 @@ static void tipc_group_add_to_tree(struct tipc_group *grp,
> > else if (key > nkey)
> > n = &(*n)->rb_right;
> > else
> > - return;
> > + return -1;
>
> Use a real error code like "-EEXIST", thank you.

Ah, I'll fix it in v2 soon, sorry about that. I saw another function in
this file returning -1.

Peilin Ye

2020-09-13 08:11:42

by Peilin Ye

[permalink] [raw]
Subject: [Linux-kernel-mentees] [PATCH net v2] tipc: Fix memory leak in tipc_group_create_member()

tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an
existing node, causing tipc_group_create_member() to leak memory. Let
tipc_group_add_to_tree() return an error in such a case, so that
tipc_group_create_member() can handle it properly.

Fixes: 75da2163dbb6 ("tipc: introduce communication groups")
Reported-and-tested-by: [email protected]
Cc: Hillf Danton <[email protected]>
Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13aff
Signed-off-by: Peilin Ye <[email protected]>
---
Change in v2:
- let tipc_group_add_to_tree() return a real error code instead of -1.
(Suggested by David Miller <[email protected]>)

net/tipc/group.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/tipc/group.c b/net/tipc/group.c
index 588c2d2b0c69..b1fcd2ad5ecf 100644
--- a/net/tipc/group.c
+++ b/net/tipc/group.c
@@ -273,8 +273,8 @@ static struct tipc_member *tipc_group_find_node(struct tipc_group *grp,
return NULL;
}

-static void tipc_group_add_to_tree(struct tipc_group *grp,
- struct tipc_member *m)
+static int tipc_group_add_to_tree(struct tipc_group *grp,
+ struct tipc_member *m)
{
u64 nkey, key = (u64)m->node << 32 | m->port;
struct rb_node **n, *parent = NULL;
@@ -291,10 +291,11 @@ static void tipc_group_add_to_tree(struct tipc_group *grp,
else if (key > nkey)
n = &(*n)->rb_right;
else
- return;
+ return -EEXIST;
}
rb_link_node(&m->tree_node, parent, n);
rb_insert_color(&m->tree_node, &grp->members);
+ return 0;
}

static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
@@ -302,6 +303,7 @@ static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
u32 instance, int state)
{
struct tipc_member *m;
+ int ret;

m = kzalloc(sizeof(*m), GFP_ATOMIC);
if (!m)
@@ -314,8 +316,12 @@ static struct tipc_member *tipc_group_create_member(struct tipc_group *grp,
m->port = port;
m->instance = instance;
m->bc_acked = grp->bc_snd_nxt - 1;
+ ret = tipc_group_add_to_tree(grp, m);
+ if (ret < 0) {
+ kfree(m);
+ return NULL;
+ }
grp->member_cnt++;
- tipc_group_add_to_tree(grp, m);
tipc_nlist_add(&grp->dests, m->node);
m->state = state;
return m;
--
2.25.1

2020-09-14 23:38:18

by David Miller

[permalink] [raw]
Subject: Re: [Linux-kernel-mentees] [PATCH net v2] tipc: Fix memory leak in tipc_group_create_member()

From: Peilin Ye <[email protected]>
Date: Sun, 13 Sep 2020 04:06:05 -0400

> tipc_group_add_to_tree() returns silently if `key` matches `nkey` of an
> existing node, causing tipc_group_create_member() to leak memory. Let
> tipc_group_add_to_tree() return an error in such a case, so that
> tipc_group_create_member() can handle it properly.
>
> Fixes: 75da2163dbb6 ("tipc: introduce communication groups")
> Reported-and-tested-by: [email protected]
> Cc: Hillf Danton <[email protected]>
> Link: https://syzkaller.appspot.com/bug?id=048390604fe1b60df34150265479202f10e13aff
> Signed-off-by: Peilin Ye <[email protected]>
> ---
> Change in v2:
> - let tipc_group_add_to_tree() return a real error code instead of -1.
> (Suggested by David Miller <[email protected]>)

Applied and queued up for -stable, thank you.