linux-dev/net/llc, branch master

net: rename reference+tracking helpers

2022-06-10T04:52:55Z

Netdev reference helpers have a dev_ prefix for historic reasons. Renaming the old helpers would be too much churn but we can rename the tracking ones which are relatively recent and should be the default for new code. Rename: dev_hold_track() -> netdev_hold() dev_put_track() -> netdev_put() dev_replace_track() -> netdev_ref_replace() Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

llc: only change llc->dev when bind() succeeds

2022-03-25T23:55:41Z

My latest patch, attempting to fix the refcount leak in a minimal way turned out to add a new bug. Whenever the bind operation fails before we attempt to grab a reference count on a device, we might release the device refcount of a prior successful bind() operation. syzbot was not happy about this [1]. Note to stable teams: Make sure commit b37a46683739 ("netdevice: add the case if dev is NULL") is already present in your trees. [1] general protection fault, probably for non-canonical address 0xdffffc0000000070: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000380-0x0000000000000387] CPU: 1 PID: 3590 Comm: syz-executor361 Tainted: G W 5.17.0-syzkaller-04796-g169e77764adc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:llc_ui_connect+0x400/0xcb0 net/llc/af_llc.c:500 Code: 80 3c 02 00 0f 85 fc 07 00 00 4c 8b a5 38 05 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 80 03 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a9 07 00 00 49 8b b4 24 80 03 00 00 4c 89 f2 48 RSP: 0018:ffffc900038cfcc0 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff8880756eb600 RCX: 0000000000000000 RDX: 0000000000000070 RSI: ffffc900038cfe3e RDI: 0000000000000380 RBP: ffff888015ee5000 R08: 0000000000000001 R09: ffff888015ee5535 R10: ffffed1002bdcaa6 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc900038cfe37 R14: ffffc900038cfe38 R15: ffff888015ee5012 FS: 0000555555acd300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000280 CR3: 0000000077db6000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __sys_connect_file+0x155/0x1a0 net/socket.c:1900 __sys_connect+0x161/0x190 net/socket.c:1917 __do_sys_connect net/socket.c:1927 [inline] __se_sys_connect net/socket.c:1924 [inline] __x64_sys_connect+0x6f/0xb0 net/socket.c:1924 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f016acb90b9 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd417947f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f016acb90b9 RDX: 0000000000000010 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00007f016ac7d0a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f016ac7d130 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:llc_ui_connect+0x400/0xcb0 net/llc/af_llc.c:500 Fixes: 764f4eb6846f ("llc: fix netdevice reference leaks in llc_ui_bind()") Signed-off-by: Eric Dumazet Reported-by: syzbot Cc: 赵子轩 Cc: Stoyan Manolov Link: https://lore.kernel.org/r/20220325035827.360418-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

llc: fix netdevice reference leaks in llc_ui_bind()

2022-03-23T17:48:00Z

Whenever llc_ui_bind() and/or llc_ui_autobind() took a reference on a netdevice but subsequently fail, they must properly release their reference or risk the infamous message from unregister_netdevice() at device dismantle. unregister_netdevice: waiting for eth0 to become free. Usage count = 3 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: 赵子轩 Reported-by: Stoyan Manolov Link: https://lore.kernel.org/r/20220323004147.1990845-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski

sock: Use sock_owned_by_user_nocheck() instead of sk_lock.owned.

2021-12-11T03:43:00Z

This patch moves sock_release_ownership() down in include/net/sock.h and replaces some sk_lock.owned tests with sock_owned_by_user_nocheck(). Signed-off-by: Kuniyuki Iwashima Link: https://lore.kernel.org/r/20211208062158.54132-1-kuniyu@amazon.co.jp Signed-off-by: Jakub Kicinski

llc: add net device refcount tracker

2021-12-08T04:44:59Z

Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

llc/snap: constify dev_addr passing

2021-10-13T16:40:46Z

In preparation for netdev->dev_addr being constant make all relevant arguments in LLC and SNAP constant. Signed-off-by: Jakub Kicinski

net: Remove redundant if statements

2021-08-05T12:27:50Z

The 'if (dev)' statement already move into dev_{put , hold}, so remove redundant if statements. Signed-off-by: Yajun Deng Signed-off-by: David S. Miller

net: llc: fix skb_over_panic

2021-07-27T12:05:56Z

Syzbot reported skb_over_panic() in llc_pdu_init_as_xid_cmd(). The problem was in wrong LCC header manipulations. Syzbot's reproducer tries to send XID packet. llc_ui_sendmsg() is doing following steps: 1. skb allocation with size = len + header size len is passed from userpace and header size is 3 since addr->sllc_xid is set. 2. skb_reserve() for header_len = 3 3. filling all other space with memcpy_from_msg() Ok, at this moment we have fully loaded skb, only headers needs to be filled. Then code comes to llc_sap_action_send_xid_c(). This function pushes 3 bytes for LLC PDU header and initializes it. Then comes llc_pdu_init_as_xid_cmd(). It initalizes next 3 bytes *AFTER* LLC PDU header and call skb_push(skb, 3). This looks wrong for 2 reasons: 1. Bytes rigth after LLC header are user data, so this function was overwriting payload. 2. skb_push(skb, 3) call can cause skb_over_panic() since all free space was filled in llc_ui_sendmsg(). (This can happen is user passed 686 len: 686 + 14 (eth header) + 3 (LLC header) = 703. SKB_DATA_ALIGN(703) = 704) So, in this patch I added 2 new private constansts: LLC_PDU_TYPE_U_XID and LLC_PDU_LEN_U_XID. LLC_PDU_LEN_U_XID is used to correctly reserve header size to handle LLC + XID case. LLC_PDU_TYPE_U_XID is used by llc_pdu_header_init() function to push 6 bytes instead of 3. And finally I removed skb_push() call from llc_pdu_init_as_xid_cmd(). This changes should not affect other parts of LLC, since after all steps we just transmit buffer. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-and-tested-by: syzbot+5e5a981ad7cc54c4b2b4@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Signed-off-by: David S. Miller

llc2: Remove redundant assignment to rc

2021-04-27T21:16:14Z

Variable rc is set to zero but this value is never read as it is overwritten with a new value later on, hence it is a redundant assignment and can be removed. Cleans up the following clang-analyzer warning: net/llc/llc_station.c:86:2: warning: Value stored to 'rc' is never read [clang-analyzer-deadcode.DeadStores]. Reported-by: Abaci Robot Signed-off-by: Jiapeng Chong Signed-off-by: David S. Miller

llc: llc_core.c: COuple of typo fixes

2021-03-29T00:31:13Z

s/searchs/searches/ ....two different places. Signed-off-by: Bhaskar Chowdhury Signed-off-by: David S. Miller