kernel/git/stable/linux.git/net/x25, branch linux-3.16.y

net/x25: fix a race in x25_bind()

2019-05-02T20:41:59+00:00

commit 797a22bd5298c2674d927893f46cadf619dad11d upstream. syzbot was able to trigger another soft lockup [1] I first thought it was the O(N^2) issue I mentioned in my prior fix (f657d22ee1f "net/x25: do not hold the cpu too long in x25_new_lci()"), but I eventually found that x25_bind() was not checking SOCK_ZAPPED state under socket lock protection. This means that multiple threads can end up calling x25_insert_socket() for the same socket, and corrupt x25_list [1] watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz-executor.2:10492] Modules linked in: irq event stamp: 27515 hardirqs last enabled at (27514): [] trace_hardirqs_on_thunk+0x1a/0x1c hardirqs last disabled at (27515): [] trace_hardirqs_off_thunk+0x1a/0x1c softirqs last enabled at (32): [] x25_get_neigh+0xa3/0xd0 net/x25/x25_link.c:336 softirqs last disabled at (34): [] x25_find_socket+0x23/0x140 net/x25/af_x25.c:341 CPU: 0 PID: 10492 Comm: syz-executor.2 Not tainted 5.0.0-rc7+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x50 kernel/kcov.c:97 Code: f4 ff ff ff e8 11 9f ea ff 48 c7 05 12 fb e5 08 00 00 00 00 e9 c8 e9 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 <48> 8b 75 08 65 48 8b 04 25 40 ee 01 00 65 8b 15 38 0c 92 7e 81 e2 RSP: 0018:ffff88806e94fc48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffff1100d84dac5 RBX: 0000000000000001 RCX: ffffc90006197000 RDX: 0000000000040000 RSI: ffffffff86324bf3 RDI: ffff88806c26d628 RBP: ffff88806e94fc48 R08: ffff88806c1c6500 R09: fffffbfff1282561 R10: fffffbfff1282560 R11: ffffffff89412b03 R12: ffff88806c26d628 R13: ffff888090455200 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f3a107e4700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3a107e3db8 CR3: 00000000a5544000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __x25_find_socket net/x25/af_x25.c:327 [inline] x25_find_socket+0x7d/0x140 net/x25/af_x25.c:342 x25_new_lci net/x25/af_x25.c:355 [inline] x25_connect+0x380/0xde0 net/x25/af_x25.c:784 __sys_connect+0x266/0x330 net/socket.c:1662 __do_sys_connect net/socket.c:1673 [inline] __se_sys_connect net/socket.c:1670 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1670 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457e29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3a107e3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457e29 RDX: 0000000000000012 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3a107e46d4 R13: 00000000004be362 R14: 00000000004ceb98 R15: 00000000ffffffff Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10493 Comm: syz-executor.3 Not tainted 5.0.0-rc7+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline] RIP: 0010:queued_write_lock_slowpath+0x143/0x290 kernel/locking/qrwlock.c:86 Code: 4c 8d 2c 01 41 83 c7 03 41 0f b6 45 00 41 38 c7 7c 08 84 c0 0f 85 0c 01 00 00 8b 03 3d 00 01 00 00 74 1a f3 90 41 0f b6 55 00 <41> 38 d7 7c eb 84 d2 74 e7 48 89 df e8 cc aa 4e 00 eb dd be 04 00 RSP: 0018:ffff888085c47bd8 EFLAGS: 00000206 RAX: 0000000000000300 RBX: ffffffff89412b00 RCX: 1ffffffff1282560 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff89412b00 RBP: ffff888085c47c70 R08: 1ffffffff1282560 R09: fffffbfff1282561 R10: fffffbfff1282560 R11: ffffffff89412b03 R12: 00000000000000ff R13: fffffbfff1282560 R14: 1ffff11010b88f7d R15: 0000000000000003 FS: 00007fdd04086700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdd04064db8 CR3: 0000000090be0000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: queued_write_lock include/asm-generic/qrwlock.h:104 [inline] do_raw_write_lock+0x1d6/0x290 kernel/locking/spinlock_debug.c:203 __raw_write_lock_bh include/linux/rwlock_api_smp.h:204 [inline] _raw_write_lock_bh+0x3b/0x50 kernel/locking/spinlock.c:312 x25_insert_socket+0x21/0xe0 net/x25/af_x25.c:267 x25_bind+0x273/0x340 net/x25/af_x25.c:703 __sys_bind+0x23f/0x290 net/socket.c:1481 __do_sys_bind net/socket.c:1492 [inline] __se_sys_bind net/socket.c:1490 [inline] __x64_sys_bind+0x73/0xb0 net/socket.c:1490 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457e29 Fixes: 90c27297a9bf ("X.25 remove bkl in bind") Signed-off-by: Eric Dumazet Cc: andrew hendry Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings

net: fix a kernel infoleak in x25 module

2016-06-15T20:29:34+00:00

commit 79e48650320e6fba48369fccf13fd045315b19b8 upstream. Stack object "dte_facilities" is allocated in x25_rx_call_request(), which is supposed to be initialized in x25_negotiate_facilities. However, 5 fields (8 bytes in total) are not initialized. This object is then copied to userland via copy_to_user, thus infoleak occurs. Signed-off-by: Kangjie Lu Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings

net: Fix use after free by removing length arg from sk_data_ready callbacks.

2014-04-11T20:15:36+00:00

Several spots in the kernel perform a sequence like: skb_queue_tail(&sk->s_receive_queue, skb); sk->sk_data_ready(sk, skb->len); But at the moment we place the SKB onto the socket receive queue it can be consumed and freed up. So this skb->len access is potentially to freed up memory. Furthermore, the skb->len can be modified by the consumer so it is possible that the value isn't accurate. And finally, no actual implementation of this callback actually uses the length argument. And since nobody actually cared about it's value, lots of call sites pass arbitrary values in such as '0' and even '1'. So just remove the length argument from the callback, that way there is no confusion whatsoever and all of these use-after-free cases get fixed as a side effect. Based upon a patch by Eric Dumazet and his suggestion to audit this issue tree-wide. Signed-off-by: David S. Miller

net: add build-time checks for msg->msg_name size

2014-01-19T07:04:16+00:00

This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg handler msg_name and msg_namelen logic"). DECLARE_SOCKADDR validates that the structure we use for writing the name information to is not larger than the buffer which is reserved for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR consistently in sendmsg code paths. Signed-off-by: Steffen Hurrle Suggested-by: Hannes Frederic Sowa Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

x25: convert printks to pr_

2013-12-10T01:24:18+00:00

use pr_ instead of printk(LEVEL) Suggested-by: Joe Perches Signed-off-by: Wang Weidong Signed-off-by: David S. Miller

net: rework recvmsg handler msg_name and msg_namelen logic

2013-11-21T02:52:30+00:00

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must set msg_namelen to the proper size <= sizeof(struct sockaddr_storage) to return msg_name to the user. This prevents numerous uninitialized memory leaks we had in the recvmsg handlers and makes it harder for new code to accidentally leak uninitialized memory. Optimize for the case recvfrom is called with NULL as address. We don't need to copy the address at all, so set it to NULL before invoking the recvmsg handler. We can do so, because all the recvmsg handlers must cope with the case a plain read() is called on them. read() also sets msg_name to NULL. Also document these changes in include/linux/net.h as suggested by David Miller. Changes since RFC: Set msg->msg_name = NULL if user specified a NULL in msg_name but had a non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't affect sendto as it would bail out earlier while trying to copy-in the address. It also more naturally reflects the logic by the callers of verify_iovec. With this change in place I could remove " if (!uaddr || msg_sys->msg_namelen == 0) msg->msg_name = NULL ". This change does not alter the user visible error logic as we ignore msg_namelen as long as msg_name is NULL. Also remove two unnecessary curly brackets in ___sys_recvmsg and change comments to netdev style. Cc: David Miller Suggested-by: Eric Dumazet Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

net: x25: Fix dead URLs in Kconfig

2013-10-29T21:35:17+00:00

Update the URLs in the Kconfig file to the new pages at sangoma.com and cisco.com Signed-off-by: Michael Drüing Signed-off-by: David S. Miller

x25: add a sanity check parsing X.25 facilities

2013-09-04T04:27:27+00:00

This was found with a manual audit and I don't have a reproducer. We limit ->calling_len and ->called_len when we get them from copy_from_user() in x25_ioctl() so when they come from skb->data then we should cap them there as well. Signed-off-by: Dan Carpenter Signed-off-by: David S. Miller

x25: Fix broken locking in ioctl error paths.

2013-07-02T01:15:25+00:00

Two of the x25 ioctl cases have error paths that break out of the function without unlocking the socket, leading to this warning: ================================================ [ BUG: lock held when returning to user space! ] 3.10.0-rc7+ #36 Not tainted ------------------------------------------------ trinity-child2/31407 is leaving the kernel with locks still held! 1 lock held by trinity-child2/31407: #0: (sk_lock-AF_X25){+.+.+.}, at: [] x25_ioctl+0x8a/0x740 [x25] Signed-off-by: Dave Jones Signed-off-by: David S. Miller

net: pass info struct via netdevice notifier

2013-05-28T20:11:01+00:00

So far, only net_device * could be passed along with netdevice notifier event. This patch provides a possibility to pass custom structure able to provide info that event listener needs to know. Signed-off-by: Jiri Pirko v2->v3: fix typo on simeth shortened dev_getter shortened notifier_info struct name v1->v2: fix notifier_call parameter in call_netdevice_notifier() Signed-off-by: David S. Miller