linux-stable.git/net/sched, branch v3.2.95 Linux kernel stable tree pkt_sched: Fix warning false positives. 2017-11-11T13:34:44+00:00 David S. Miller davem@davemloft.net 2012-09-27T22:35:47+00:00 a01e2a853c9aa6ca4e5c5f734e151b5cae9efd9b commit f54ba7798848ce1385a71b36a2c997422c82220a upstream. GCC refuses to recognize that all error control flows do in fact set err to something. Add an explicit initialization to shut it up. net/sched/sch_drr.c: In function ‘drr_enqueue’: net/sched/sch_drr.c:359:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized] net/sched/sch_qfq.c: In function ‘qfq_enqueue’: net/sched/sch_qfq.c:885:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized] Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit f54ba7798848ce1385a71b36a2c997422c82220a upstream.

GCC refuses to recognize that all error control flows do in fact
set err to something.

Add an explicit initialization to shut it up.

net/sched/sch_drr.c: In function ‘drr_enqueue’:
net/sched/sch_drr.c:359:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized]
net/sched/sch_qfq.c: In function ‘qfq_enqueue’:
net/sched/sch_qfq.c:885:11: warning: ‘err’ may be used uninitialized in this function [-Wmaybe-uninitialized]

Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_tbf: fix two null pointer dereferences on init failure 2017-11-11T13:34:37+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:49:05+00:00 cc6db6b3a840a4914ba34e4507ac8fcfcca85500 commit c2d6511e6a4f1f3673d711569c00c3849549e9b0 upstream. sch_tbf calls qdisc_watchdog_cancel() in both its ->reset and ->destroy callbacks but it may fail before the timer is initialized due to missing options (either not supplied by user-space or set as a default qdisc), also q->qdisc is used by ->reset and ->destroy so we need it initialized. Reproduce: $ sysctl net.core.default_qdisc=tbf $ ip l set ethX up Crash log: [ 959.160172] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 959.160323] IP: qdisc_reset+0xa/0x5c [ 959.160400] PGD 59cdb067 [ 959.160401] P4D 59cdb067 [ 959.160466] PUD 59ccb067 [ 959.160532] PMD 0 [ 959.160597] [ 959.160706] Oops: 0000 [#1] SMP [ 959.160778] Modules linked in: sch_tbf sch_sfb sch_prio sch_netem [ 959.160891] CPU: 2 PID: 1562 Comm: ip Not tainted 4.13.0-rc6+ #62 [ 959.160998] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 959.161157] task: ffff880059c9a700 task.stack: ffff8800376d0000 [ 959.161263] RIP: 0010:qdisc_reset+0xa/0x5c [ 959.161347] RSP: 0018:ffff8800376d3610 EFLAGS: 00010286 [ 959.161531] RAX: ffffffffa001b1dd RBX: ffff8800373a2800 RCX: 0000000000000000 [ 959.161733] RDX: ffffffff8215f160 RSI: ffffffff8215f160 RDI: 0000000000000000 [ 959.161939] RBP: ffff8800376d3618 R08: 00000000014080c0 R09: 00000000ffffffff [ 959.162141] R10: ffff8800376d3578 R11: 0000000000000020 R12: ffffffffa001d2c0 [ 959.162343] R13: ffff880037538000 R14: 00000000ffffffff R15: 0000000000000001 [ 959.162546] FS: 00007fcc5126b740(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000 [ 959.162844] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 959.163030] CR2: 0000000000000018 CR3: 000000005abc4000 CR4: 00000000000406e0 [ 959.163233] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 959.163436] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 959.163638] Call Trace: [ 959.163788] tbf_reset+0x19/0x64 [sch_tbf] [ 959.163957] qdisc_destroy+0x8b/0xe5 [ 959.164119] qdisc_create_dflt+0x86/0x94 [ 959.164284] ? dev_activate+0x129/0x129 [ 959.164449] attach_one_default_qdisc+0x36/0x63 [ 959.164623] netdev_for_each_tx_queue+0x3d/0x48 [ 959.164795] dev_activate+0x4b/0x129 [ 959.164957] __dev_open+0xe7/0x104 [ 959.165118] __dev_change_flags+0xc6/0x15c [ 959.165287] dev_change_flags+0x25/0x59 [ 959.165451] do_setlink+0x30c/0xb3f [ 959.165613] ? check_chain_key+0xb0/0xfd [ 959.165782] rtnl_newlink+0x3a4/0x729 [ 959.165947] ? rtnl_newlink+0x117/0x729 [ 959.166121] ? ns_capable_common+0xd/0xb1 [ 959.166288] ? ns_capable+0x13/0x15 [ 959.166450] rtnetlink_rcv_msg+0x188/0x197 [ 959.166617] ? rcu_read_unlock+0x3e/0x5f [ 959.166783] ? rtnl_newlink+0x729/0x729 [ 959.166948] netlink_rcv_skb+0x6c/0xce [ 959.167113] rtnetlink_rcv+0x23/0x2a [ 959.167273] netlink_unicast+0x103/0x181 [ 959.167439] netlink_sendmsg+0x326/0x337 [ 959.167607] sock_sendmsg_nosec+0x14/0x3f [ 959.167772] sock_sendmsg+0x29/0x2e [ 959.167932] ___sys_sendmsg+0x209/0x28b [ 959.168098] ? do_raw_spin_unlock+0xcd/0xf8 [ 959.168267] ? _raw_spin_unlock+0x27/0x31 [ 959.168432] ? __handle_mm_fault+0x651/0xdb1 [ 959.168602] ? check_chain_key+0xb0/0xfd [ 959.168773] __sys_sendmsg+0x45/0x63 [ 959.168934] ? __sys_sendmsg+0x45/0x63 [ 959.169100] SyS_sendmsg+0x19/0x1b [ 959.169260] entry_SYSCALL_64_fastpath+0x23/0xc2 [ 959.169432] RIP: 0033:0x7fcc5097e690 [ 959.169592] RSP: 002b:00007ffd0d5c7b48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 959.169887] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007fcc5097e690 [ 959.170089] RDX: 0000000000000000 RSI: 00007ffd0d5c7b90 RDI: 0000000000000003 [ 959.170292] RBP: ffff8800376d3f98 R08: 0000000000000001 R09: 0000000000000003 [ 959.170494] R10: 00007ffd0d5c7910 R11: 0000000000000246 R12: 0000000000000006 [ 959.170697] R13: 000000000066f1a0 R14: 00007ffd0d5cfc40 R15: 0000000000000000 [ 959.170900] ? trace_hardirqs_off_caller+0xa7/0xcf [ 959.171076] Code: 00 41 c7 84 24 14 01 00 00 00 00 00 00 41 c7 84 24 98 00 00 00 00 00 00 00 41 5c 41 5d 41 5e 5d c3 66 66 66 66 90 55 48 89 e5 53 <48> 8b 47 18 48 89 fb 48 8b 40 48 48 85 c0 74 02 ff d0 48 8b bb [ 959.171637] RIP: qdisc_reset+0xa/0x5c RSP: ffff8800376d3610 [ 959.171821] CR2: 0000000000000018 Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit c2d6511e6a4f1f3673d711569c00c3849549e9b0 upstream.

sch_tbf calls qdisc_watchdog_cancel() in both its ->reset and ->destroy
callbacks but it may fail before the timer is initialized due to missing
options (either not supplied by user-space or set as a default qdisc),
also q->qdisc is used by ->reset and ->destroy so we need it initialized.

Reproduce:
$ sysctl net.core.default_qdisc=tbf
$ ip l set ethX up

Crash log:
[  959.160172] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[  959.160323] IP: qdisc_reset+0xa/0x5c
[  959.160400] PGD 59cdb067
[  959.160401] P4D 59cdb067
[  959.160466] PUD 59ccb067
[  959.160532] PMD 0
[  959.160597]
[  959.160706] Oops: 0000 [#1] SMP
[  959.160778] Modules linked in: sch_tbf sch_sfb sch_prio sch_netem
[  959.160891] CPU: 2 PID: 1562 Comm: ip Not tainted 4.13.0-rc6+ #62
[  959.160998] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[  959.161157] task: ffff880059c9a700 task.stack: ffff8800376d0000
[  959.161263] RIP: 0010:qdisc_reset+0xa/0x5c
[  959.161347] RSP: 0018:ffff8800376d3610 EFLAGS: 00010286
[  959.161531] RAX: ffffffffa001b1dd RBX: ffff8800373a2800 RCX: 0000000000000000
[  959.161733] RDX: ffffffff8215f160 RSI: ffffffff8215f160 RDI: 0000000000000000
[  959.161939] RBP: ffff8800376d3618 R08: 00000000014080c0 R09: 00000000ffffffff
[  959.162141] R10: ffff8800376d3578 R11: 0000000000000020 R12: ffffffffa001d2c0
[  959.162343] R13: ffff880037538000 R14: 00000000ffffffff R15: 0000000000000001
[  959.162546] FS:  00007fcc5126b740(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000
[  959.162844] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  959.163030] CR2: 0000000000000018 CR3: 000000005abc4000 CR4: 00000000000406e0
[  959.163233] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  959.163436] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  959.163638] Call Trace:
[  959.163788]  tbf_reset+0x19/0x64 [sch_tbf]
[  959.163957]  qdisc_destroy+0x8b/0xe5
[  959.164119]  qdisc_create_dflt+0x86/0x94
[  959.164284]  ? dev_activate+0x129/0x129
[  959.164449]  attach_one_default_qdisc+0x36/0x63
[  959.164623]  netdev_for_each_tx_queue+0x3d/0x48
[  959.164795]  dev_activate+0x4b/0x129
[  959.164957]  __dev_open+0xe7/0x104
[  959.165118]  __dev_change_flags+0xc6/0x15c
[  959.165287]  dev_change_flags+0x25/0x59
[  959.165451]  do_setlink+0x30c/0xb3f
[  959.165613]  ? check_chain_key+0xb0/0xfd
[  959.165782]  rtnl_newlink+0x3a4/0x729
[  959.165947]  ? rtnl_newlink+0x117/0x729
[  959.166121]  ? ns_capable_common+0xd/0xb1
[  959.166288]  ? ns_capable+0x13/0x15
[  959.166450]  rtnetlink_rcv_msg+0x188/0x197
[  959.166617]  ? rcu_read_unlock+0x3e/0x5f
[  959.166783]  ? rtnl_newlink+0x729/0x729
[  959.166948]  netlink_rcv_skb+0x6c/0xce
[  959.167113]  rtnetlink_rcv+0x23/0x2a
[  959.167273]  netlink_unicast+0x103/0x181
[  959.167439]  netlink_sendmsg+0x326/0x337
[  959.167607]  sock_sendmsg_nosec+0x14/0x3f
[  959.167772]  sock_sendmsg+0x29/0x2e
[  959.167932]  ___sys_sendmsg+0x209/0x28b
[  959.168098]  ? do_raw_spin_unlock+0xcd/0xf8
[  959.168267]  ? _raw_spin_unlock+0x27/0x31
[  959.168432]  ? __handle_mm_fault+0x651/0xdb1
[  959.168602]  ? check_chain_key+0xb0/0xfd
[  959.168773]  __sys_sendmsg+0x45/0x63
[  959.168934]  ? __sys_sendmsg+0x45/0x63
[  959.169100]  SyS_sendmsg+0x19/0x1b
[  959.169260]  entry_SYSCALL_64_fastpath+0x23/0xc2
[  959.169432] RIP: 0033:0x7fcc5097e690
[  959.169592] RSP: 002b:00007ffd0d5c7b48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  959.169887] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007fcc5097e690
[  959.170089] RDX: 0000000000000000 RSI: 00007ffd0d5c7b90 RDI: 0000000000000003
[  959.170292] RBP: ffff8800376d3f98 R08: 0000000000000001 R09: 0000000000000003
[  959.170494] R10: 00007ffd0d5c7910 R11: 0000000000000246 R12: 0000000000000006
[  959.170697] R13: 000000000066f1a0 R14: 00007ffd0d5cfc40 R15: 0000000000000000
[  959.170900]  ? trace_hardirqs_off_caller+0xa7/0xcf
[  959.171076] Code: 00 41 c7 84 24 14 01 00 00 00 00 00 00 41 c7 84 24
98 00 00 00 00 00 00 00 41 5c 41 5d 41 5e 5d c3 66 66 66 66 90 55 48 89
e5 53 <48> 8b 47 18 48 89 fb 48 8b 40 48 48 85 c0 74 02 ff d0 48 8b bb
[  959.171637] RIP: qdisc_reset+0xa/0x5c RSP: ffff8800376d3610
[  959.171821] CR2: 0000000000000018

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_netem: avoid null pointer deref on init failure 2017-11-11T13:34:37+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:49:03+00:00 d1e4c9f184408fb9282a9c17a976cb8fe1fb49d8 commit 634576a1844dba15bc5e6fc61d72f37e13a21615 upstream. netem can fail in ->init due to missing options (either not supplied by user-space or used as a default qdisc) causing a timer->base null pointer deref in its ->destroy() and ->reset() callbacks. Reproduce: $ sysctl net.core.default_qdisc=netem $ ip l set ethX up Crash log: [ 1814.846943] BUG: unable to handle kernel NULL pointer dereference at (null) [ 1814.847181] IP: hrtimer_active+0x17/0x8a [ 1814.847270] PGD 59c34067 [ 1814.847271] P4D 59c34067 [ 1814.847337] PUD 37374067 [ 1814.847403] PMD 0 [ 1814.847468] [ 1814.847582] Oops: 0000 [#1] SMP [ 1814.847655] Modules linked in: sch_netem(O) sch_fq_codel(O) [ 1814.847761] CPU: 3 PID: 1573 Comm: ip Tainted: G O 4.13.0-rc6+ #62 [ 1814.847884] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 1814.848043] task: ffff88003723a700 task.stack: ffff88005adc8000 [ 1814.848235] RIP: 0010:hrtimer_active+0x17/0x8a [ 1814.848407] RSP: 0018:ffff88005adcb590 EFLAGS: 00010246 [ 1814.848590] RAX: 0000000000000000 RBX: ffff880058e359d8 RCX: 0000000000000000 [ 1814.848793] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880058e359d8 [ 1814.848998] RBP: ffff88005adcb5b0 R08: 00000000014080c0 R09: 00000000ffffffff [ 1814.849204] R10: ffff88005adcb660 R11: 0000000000000020 R12: 0000000000000000 [ 1814.849410] R13: ffff880058e359d8 R14: 00000000ffffffff R15: 0000000000000001 [ 1814.849616] FS: 00007f733bbca740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000 [ 1814.849919] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1814.850107] CR2: 0000000000000000 CR3: 0000000059f0d000 CR4: 00000000000406e0 [ 1814.850313] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1814.850518] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1814.850723] Call Trace: [ 1814.850875] hrtimer_try_to_cancel+0x1a/0x93 [ 1814.851047] hrtimer_cancel+0x15/0x20 [ 1814.851211] qdisc_watchdog_cancel+0x12/0x14 [ 1814.851383] netem_reset+0xe6/0xed [sch_netem] [ 1814.851561] qdisc_destroy+0x8b/0xe5 [ 1814.851723] qdisc_create_dflt+0x86/0x94 [ 1814.851890] ? dev_activate+0x129/0x129 [ 1814.852057] attach_one_default_qdisc+0x36/0x63 [ 1814.852232] netdev_for_each_tx_queue+0x3d/0x48 [ 1814.852406] dev_activate+0x4b/0x129 [ 1814.852569] __dev_open+0xe7/0x104 [ 1814.852730] __dev_change_flags+0xc6/0x15c [ 1814.852899] dev_change_flags+0x25/0x59 [ 1814.853064] do_setlink+0x30c/0xb3f [ 1814.853228] ? check_chain_key+0xb0/0xfd [ 1814.853396] ? check_chain_key+0xb0/0xfd [ 1814.853565] rtnl_newlink+0x3a4/0x729 [ 1814.853728] ? rtnl_newlink+0x117/0x729 [ 1814.853905] ? ns_capable_common+0xd/0xb1 [ 1814.854072] ? ns_capable+0x13/0x15 [ 1814.854234] rtnetlink_rcv_msg+0x188/0x197 [ 1814.854404] ? rcu_read_unlock+0x3e/0x5f [ 1814.854572] ? rtnl_newlink+0x729/0x729 [ 1814.854737] netlink_rcv_skb+0x6c/0xce [ 1814.854902] rtnetlink_rcv+0x23/0x2a [ 1814.855064] netlink_unicast+0x103/0x181 [ 1814.855230] netlink_sendmsg+0x326/0x337 [ 1814.855398] sock_sendmsg_nosec+0x14/0x3f [ 1814.855584] sock_sendmsg+0x29/0x2e [ 1814.855747] ___sys_sendmsg+0x209/0x28b [ 1814.855912] ? do_raw_spin_unlock+0xcd/0xf8 [ 1814.856082] ? _raw_spin_unlock+0x27/0x31 [ 1814.856251] ? __handle_mm_fault+0x651/0xdb1 [ 1814.856421] ? check_chain_key+0xb0/0xfd [ 1814.856592] __sys_sendmsg+0x45/0x63 [ 1814.856755] ? __sys_sendmsg+0x45/0x63 [ 1814.856923] SyS_sendmsg+0x19/0x1b [ 1814.857083] entry_SYSCALL_64_fastpath+0x23/0xc2 [ 1814.857256] RIP: 0033:0x7f733b2dd690 [ 1814.857419] RSP: 002b:00007ffe1d3387d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 1814.858238] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f733b2dd690 [ 1814.858445] RDX: 0000000000000000 RSI: 00007ffe1d338820 RDI: 0000000000000003 [ 1814.858651] RBP: ffff88005adcbf98 R08: 0000000000000001 R09: 0000000000000003 [ 1814.858856] R10: 00007ffe1d3385a0 R11: 0000000000000246 R12: 0000000000000002 [ 1814.859060] R13: 000000000066f1a0 R14: 00007ffe1d3408d0 R15: 0000000000000000 [ 1814.859267] ? trace_hardirqs_off_caller+0xa7/0xcf [ 1814.859446] Code: 10 55 48 89 c7 48 89 e5 e8 45 a1 fb ff 31 c0 5d c3 31 c0 c3 66 66 66 66 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd 49 8b 45 30 <4c> 8b 20 41 8b 5c 24 38 31 c9 31 d2 48 c7 c7 50 8e 1d 82 41 89 [ 1814.860022] RIP: hrtimer_active+0x17/0x8a RSP: ffff88005adcb590 [ 1814.860214] CR2: 0000000000000000 Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 634576a1844dba15bc5e6fc61d72f37e13a21615 upstream.

netem can fail in ->init due to missing options (either not supplied by
user-space or used as a default qdisc) causing a timer->base null
pointer deref in its ->destroy() and ->reset() callbacks.

Reproduce:
$ sysctl net.core.default_qdisc=netem
$ ip l set ethX up

Crash log:
[ 1814.846943] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1814.847181] IP: hrtimer_active+0x17/0x8a
[ 1814.847270] PGD 59c34067
[ 1814.847271] P4D 59c34067
[ 1814.847337] PUD 37374067
[ 1814.847403] PMD 0
[ 1814.847468]
[ 1814.847582] Oops: 0000 [#1] SMP
[ 1814.847655] Modules linked in: sch_netem(O) sch_fq_codel(O)
[ 1814.847761] CPU: 3 PID: 1573 Comm: ip Tainted: G           O 4.13.0-rc6+ #62
[ 1814.847884] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 1814.848043] task: ffff88003723a700 task.stack: ffff88005adc8000
[ 1814.848235] RIP: 0010:hrtimer_active+0x17/0x8a
[ 1814.848407] RSP: 0018:ffff88005adcb590 EFLAGS: 00010246
[ 1814.848590] RAX: 0000000000000000 RBX: ffff880058e359d8 RCX: 0000000000000000
[ 1814.848793] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880058e359d8
[ 1814.848998] RBP: ffff88005adcb5b0 R08: 00000000014080c0 R09: 00000000ffffffff
[ 1814.849204] R10: ffff88005adcb660 R11: 0000000000000020 R12: 0000000000000000
[ 1814.849410] R13: ffff880058e359d8 R14: 00000000ffffffff R15: 0000000000000001
[ 1814.849616] FS:  00007f733bbca740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 1814.849919] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1814.850107] CR2: 0000000000000000 CR3: 0000000059f0d000 CR4: 00000000000406e0
[ 1814.850313] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1814.850518] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1814.850723] Call Trace:
[ 1814.850875]  hrtimer_try_to_cancel+0x1a/0x93
[ 1814.851047]  hrtimer_cancel+0x15/0x20
[ 1814.851211]  qdisc_watchdog_cancel+0x12/0x14
[ 1814.851383]  netem_reset+0xe6/0xed [sch_netem]
[ 1814.851561]  qdisc_destroy+0x8b/0xe5
[ 1814.851723]  qdisc_create_dflt+0x86/0x94
[ 1814.851890]  ? dev_activate+0x129/0x129
[ 1814.852057]  attach_one_default_qdisc+0x36/0x63
[ 1814.852232]  netdev_for_each_tx_queue+0x3d/0x48
[ 1814.852406]  dev_activate+0x4b/0x129
[ 1814.852569]  __dev_open+0xe7/0x104
[ 1814.852730]  __dev_change_flags+0xc6/0x15c
[ 1814.852899]  dev_change_flags+0x25/0x59
[ 1814.853064]  do_setlink+0x30c/0xb3f
[ 1814.853228]  ? check_chain_key+0xb0/0xfd
[ 1814.853396]  ? check_chain_key+0xb0/0xfd
[ 1814.853565]  rtnl_newlink+0x3a4/0x729
[ 1814.853728]  ? rtnl_newlink+0x117/0x729
[ 1814.853905]  ? ns_capable_common+0xd/0xb1
[ 1814.854072]  ? ns_capable+0x13/0x15
[ 1814.854234]  rtnetlink_rcv_msg+0x188/0x197
[ 1814.854404]  ? rcu_read_unlock+0x3e/0x5f
[ 1814.854572]  ? rtnl_newlink+0x729/0x729
[ 1814.854737]  netlink_rcv_skb+0x6c/0xce
[ 1814.854902]  rtnetlink_rcv+0x23/0x2a
[ 1814.855064]  netlink_unicast+0x103/0x181
[ 1814.855230]  netlink_sendmsg+0x326/0x337
[ 1814.855398]  sock_sendmsg_nosec+0x14/0x3f
[ 1814.855584]  sock_sendmsg+0x29/0x2e
[ 1814.855747]  ___sys_sendmsg+0x209/0x28b
[ 1814.855912]  ? do_raw_spin_unlock+0xcd/0xf8
[ 1814.856082]  ? _raw_spin_unlock+0x27/0x31
[ 1814.856251]  ? __handle_mm_fault+0x651/0xdb1
[ 1814.856421]  ? check_chain_key+0xb0/0xfd
[ 1814.856592]  __sys_sendmsg+0x45/0x63
[ 1814.856755]  ? __sys_sendmsg+0x45/0x63
[ 1814.856923]  SyS_sendmsg+0x19/0x1b
[ 1814.857083]  entry_SYSCALL_64_fastpath+0x23/0xc2
[ 1814.857256] RIP: 0033:0x7f733b2dd690
[ 1814.857419] RSP: 002b:00007ffe1d3387d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 1814.858238] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f733b2dd690
[ 1814.858445] RDX: 0000000000000000 RSI: 00007ffe1d338820 RDI: 0000000000000003
[ 1814.858651] RBP: ffff88005adcbf98 R08: 0000000000000001 R09: 0000000000000003
[ 1814.858856] R10: 00007ffe1d3385a0 R11: 0000000000000246 R12: 0000000000000002
[ 1814.859060] R13: 000000000066f1a0 R14: 00007ffe1d3408d0 R15: 0000000000000000
[ 1814.859267]  ? trace_hardirqs_off_caller+0xa7/0xcf
[ 1814.859446] Code: 10 55 48 89 c7 48 89 e5 e8 45 a1 fb ff 31 c0 5d c3
31 c0 c3 66 66 66 66 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd 49 8b
45 30 <4c> 8b 20 41 8b 5c 24 38 31 c9 31 d2 48 c7 c7 50 8e 1d 82 41 89
[ 1814.860022] RIP: hrtimer_active+0x17/0x8a RSP: ffff88005adcb590
[ 1814.860214] CR2: 0000000000000000

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_cbq: fix null pointer dereferences on init failure 2017-11-11T13:34:37+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:49:01+00:00 bab76fa57b0a989367a247dc415ced410367444a commit 3501d059921246ff617b43e86250a719c140bd97 upstream. CBQ can fail on ->init by wrong nl attributes or simply for missing any, f.e. if it's set as a default qdisc then TCA_OPTIONS (opt) will be NULL when it is activated. The first thing init does is parse opt but it will dereference a null pointer if used as a default qdisc, also since init failure at default qdisc invokes ->reset() which cancels all timers then we'll also dereference two more null pointers (timer->base) as they were never initialized. To reproduce: $ sysctl net.core.default_qdisc=cbq $ ip l set ethX up Crash log of the first null ptr deref: [44727.907454] BUG: unable to handle kernel NULL pointer dereference at (null) [44727.907600] IP: cbq_init+0x27/0x205 [44727.907676] PGD 59ff4067 [44727.907677] P4D 59ff4067 [44727.907742] PUD 59c70067 [44727.907807] PMD 0 [44727.907873] [44727.907982] Oops: 0000 [#1] SMP [44727.908054] Modules linked in: [44727.908126] CPU: 1 PID: 21312 Comm: ip Not tainted 4.13.0-rc6+ #60 [44727.908235] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [44727.908477] task: ffff88005ad42700 task.stack: ffff880037214000 [44727.908672] RIP: 0010:cbq_init+0x27/0x205 [44727.908838] RSP: 0018:ffff8800372175f0 EFLAGS: 00010286 [44727.909018] RAX: ffffffff816c3852 RBX: ffff880058c53800 RCX: 0000000000000000 [44727.909222] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff8800372175f8 [44727.909427] RBP: ffff880037217650 R08: ffffffff81b0f380 R09: 0000000000000000 [44727.909631] R10: ffff880037217660 R11: 0000000000000020 R12: ffffffff822a44c0 [44727.909835] R13: ffff880058b92000 R14: 00000000ffffffff R15: 0000000000000001 [44727.910040] FS: 00007ff8bc583740(0000) GS:ffff88005d880000(0000) knlGS:0000000000000000 [44727.910339] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [44727.910525] CR2: 0000000000000000 CR3: 00000000371e5000 CR4: 00000000000406e0 [44727.910731] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [44727.910936] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [44727.911141] Call Trace: [44727.911291] ? lockdep_init_map+0xb6/0x1ba [44727.911461] ? qdisc_alloc+0x14e/0x187 [44727.911626] qdisc_create_dflt+0x7a/0x94 [44727.911794] ? dev_activate+0x129/0x129 [44727.911959] attach_one_default_qdisc+0x36/0x63 [44727.912132] netdev_for_each_tx_queue+0x3d/0x48 [44727.912305] dev_activate+0x4b/0x129 [44727.912468] __dev_open+0xe7/0x104 [44727.912631] __dev_change_flags+0xc6/0x15c [44727.912799] dev_change_flags+0x25/0x59 [44727.912966] do_setlink+0x30c/0xb3f [44727.913129] ? check_chain_key+0xb0/0xfd [44727.913294] ? check_chain_key+0xb0/0xfd [44727.913463] rtnl_newlink+0x3a4/0x729 [44727.913626] ? rtnl_newlink+0x117/0x729 [44727.913801] ? ns_capable_common+0xd/0xb1 [44727.913968] ? ns_capable+0x13/0x15 [44727.914131] rtnetlink_rcv_msg+0x188/0x197 [44727.914300] ? rcu_read_unlock+0x3e/0x5f [44727.914465] ? rtnl_newlink+0x729/0x729 [44727.914630] netlink_rcv_skb+0x6c/0xce [44727.914796] rtnetlink_rcv+0x23/0x2a [44727.914956] netlink_unicast+0x103/0x181 [44727.915122] netlink_sendmsg+0x326/0x337 [44727.915291] sock_sendmsg_nosec+0x14/0x3f [44727.915459] sock_sendmsg+0x29/0x2e [44727.915619] ___sys_sendmsg+0x209/0x28b [44727.915784] ? do_raw_spin_unlock+0xcd/0xf8 [44727.915954] ? _raw_spin_unlock+0x27/0x31 [44727.916121] ? __handle_mm_fault+0x651/0xdb1 [44727.916290] ? check_chain_key+0xb0/0xfd [44727.916461] __sys_sendmsg+0x45/0x63 [44727.916626] ? __sys_sendmsg+0x45/0x63 [44727.916792] SyS_sendmsg+0x19/0x1b [44727.916950] entry_SYSCALL_64_fastpath+0x23/0xc2 [44727.917125] RIP: 0033:0x7ff8bbc96690 [44727.917286] RSP: 002b:00007ffc360991e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [44727.917579] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007ff8bbc96690 [44727.917783] RDX: 0000000000000000 RSI: 00007ffc36099230 RDI: 0000000000000003 [44727.917987] RBP: ffff880037217f98 R08: 0000000000000001 R09: 0000000000000003 [44727.918190] R10: 00007ffc36098fb0 R11: 0000000000000246 R12: 0000000000000006 [44727.918393] R13: 000000000066f1a0 R14: 00007ffc360a12e0 R15: 0000000000000000 [44727.918597] ? trace_hardirqs_off_caller+0xa7/0xcf [44727.918774] Code: 41 5f 5d c3 66 66 66 66 90 55 48 8d 56 04 45 31 c9 49 c7 c0 80 f3 b0 81 48 89 e5 41 55 41 54 53 48 89 fb 48 8d 7d a8 48 83 ec 48 <0f> b7 0e be 07 00 00 00 83 e9 04 e8 e6 f7 d8 ff 85 c0 0f 88 bb [44727.919332] RIP: cbq_init+0x27/0x205 RSP: ffff8800372175f0 [44727.919516] CR2: 0000000000000000 Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: - Keep using HRTIMER_MODE_ABS - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 3501d059921246ff617b43e86250a719c140bd97 upstream.

CBQ can fail on ->init by wrong nl attributes or simply for missing any,
f.e. if it's set as a default qdisc then TCA_OPTIONS (opt) will be NULL
when it is activated. The first thing init does is parse opt but it will
dereference a null pointer if used as a default qdisc, also since init
failure at default qdisc invokes ->reset() which cancels all timers then
we'll also dereference two more null pointers (timer->base) as they were
never initialized.

To reproduce:
$ sysctl net.core.default_qdisc=cbq
$ ip l set ethX up

Crash log of the first null ptr deref:
[44727.907454] BUG: unable to handle kernel NULL pointer dereference at (null)
[44727.907600] IP: cbq_init+0x27/0x205
[44727.907676] PGD 59ff4067
[44727.907677] P4D 59ff4067
[44727.907742] PUD 59c70067
[44727.907807] PMD 0
[44727.907873]
[44727.907982] Oops: 0000 [#1] SMP
[44727.908054] Modules linked in:
[44727.908126] CPU: 1 PID: 21312 Comm: ip Not tainted 4.13.0-rc6+ #60
[44727.908235] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[44727.908477] task: ffff88005ad42700 task.stack: ffff880037214000
[44727.908672] RIP: 0010:cbq_init+0x27/0x205
[44727.908838] RSP: 0018:ffff8800372175f0 EFLAGS: 00010286
[44727.909018] RAX: ffffffff816c3852 RBX: ffff880058c53800 RCX: 0000000000000000
[44727.909222] RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffff8800372175f8
[44727.909427] RBP: ffff880037217650 R08: ffffffff81b0f380 R09: 0000000000000000
[44727.909631] R10: ffff880037217660 R11: 0000000000000020 R12: ffffffff822a44c0
[44727.909835] R13: ffff880058b92000 R14: 00000000ffffffff R15: 0000000000000001
[44727.910040] FS:  00007ff8bc583740(0000) GS:ffff88005d880000(0000) knlGS:0000000000000000
[44727.910339] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[44727.910525] CR2: 0000000000000000 CR3: 00000000371e5000 CR4: 00000000000406e0
[44727.910731] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[44727.910936] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[44727.911141] Call Trace:
[44727.911291]  ? lockdep_init_map+0xb6/0x1ba
[44727.911461]  ? qdisc_alloc+0x14e/0x187
[44727.911626]  qdisc_create_dflt+0x7a/0x94
[44727.911794]  ? dev_activate+0x129/0x129
[44727.911959]  attach_one_default_qdisc+0x36/0x63
[44727.912132]  netdev_for_each_tx_queue+0x3d/0x48
[44727.912305]  dev_activate+0x4b/0x129
[44727.912468]  __dev_open+0xe7/0x104
[44727.912631]  __dev_change_flags+0xc6/0x15c
[44727.912799]  dev_change_flags+0x25/0x59
[44727.912966]  do_setlink+0x30c/0xb3f
[44727.913129]  ? check_chain_key+0xb0/0xfd
[44727.913294]  ? check_chain_key+0xb0/0xfd
[44727.913463]  rtnl_newlink+0x3a4/0x729
[44727.913626]  ? rtnl_newlink+0x117/0x729
[44727.913801]  ? ns_capable_common+0xd/0xb1
[44727.913968]  ? ns_capable+0x13/0x15
[44727.914131]  rtnetlink_rcv_msg+0x188/0x197
[44727.914300]  ? rcu_read_unlock+0x3e/0x5f
[44727.914465]  ? rtnl_newlink+0x729/0x729
[44727.914630]  netlink_rcv_skb+0x6c/0xce
[44727.914796]  rtnetlink_rcv+0x23/0x2a
[44727.914956]  netlink_unicast+0x103/0x181
[44727.915122]  netlink_sendmsg+0x326/0x337
[44727.915291]  sock_sendmsg_nosec+0x14/0x3f
[44727.915459]  sock_sendmsg+0x29/0x2e
[44727.915619]  ___sys_sendmsg+0x209/0x28b
[44727.915784]  ? do_raw_spin_unlock+0xcd/0xf8
[44727.915954]  ? _raw_spin_unlock+0x27/0x31
[44727.916121]  ? __handle_mm_fault+0x651/0xdb1
[44727.916290]  ? check_chain_key+0xb0/0xfd
[44727.916461]  __sys_sendmsg+0x45/0x63
[44727.916626]  ? __sys_sendmsg+0x45/0x63
[44727.916792]  SyS_sendmsg+0x19/0x1b
[44727.916950]  entry_SYSCALL_64_fastpath+0x23/0xc2
[44727.917125] RIP: 0033:0x7ff8bbc96690
[44727.917286] RSP: 002b:00007ffc360991e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[44727.917579] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007ff8bbc96690
[44727.917783] RDX: 0000000000000000 RSI: 00007ffc36099230 RDI: 0000000000000003
[44727.917987] RBP: ffff880037217f98 R08: 0000000000000001 R09: 0000000000000003
[44727.918190] R10: 00007ffc36098fb0 R11: 0000000000000246 R12: 0000000000000006
[44727.918393] R13: 000000000066f1a0 R14: 00007ffc360a12e0 R15: 0000000000000000
[44727.918597]  ? trace_hardirqs_off_caller+0xa7/0xcf
[44727.918774] Code: 41 5f 5d c3 66 66 66 66 90 55 48 8d 56 04 45 31 c9
49 c7 c0 80 f3 b0 81 48 89 e5 41 55 41 54 53 48 89 fb 48 8d 7d a8 48 83
ec 48 <0f> b7 0e be 07 00 00 00 83 e9 04 e8 e6 f7 d8 ff 85 c0 0f 88 bb
[44727.919332] RIP: cbq_init+0x27/0x205 RSP: ffff8800372175f0
[44727.919516] CR2: 0000000000000000

Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2:
 - Keep using HRTIMER_MODE_ABS
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_hfsc: fix null pointer deref and double free on init failure 2017-11-11T13:34:36+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:49:00+00:00 c80cb643423d8ea1748f57c51480742f554830ec commit 3bdac362a2f89ed3e148fa6f38c5f5d858f50b1a upstream. Depending on where ->init fails we can get a null pointer deref due to uninitialized hires timer (watchdog) or a double free of the qdisc hash because it is already freed by ->destroy(). Fixes: 8d5537387505 ("net/sched/hfsc: allocate tcf block for hfsc root class") Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: sch_hfsc doesn't use a tcf block] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 3bdac362a2f89ed3e148fa6f38c5f5d858f50b1a upstream.

Depending on where ->init fails we can get a null pointer deref due to
uninitialized hires timer (watchdog) or a double free of the qdisc hash
because it is already freed by ->destroy().

Fixes: 8d5537387505 ("net/sched/hfsc: allocate tcf block for hfsc root class")
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: sch_hfsc doesn't use a tcf block]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_multiq: fix double free on init failure 2017-11-11T13:34:36+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:48:58+00:00 1c2197aa2ed034eb01faf94aa0b4e3a972216244 commit e89d469e3be3ed3d7124a803211a463ff83d0964 upstream. The below commit added a call to ->destroy() on init failure, but multiq still frees ->queues on error in init, but ->queues is also freed by ->destroy() thus we get double free and corrupted memory. Very easy to reproduce (eth0 not multiqueue): $ tc qdisc add dev eth0 root multiq RTNETLINK answers: Operation not supported $ ip l add dumdum type dummy (crash) Trace log: [ 3929.467747] general protection fault: 0000 [#1] SMP [ 3929.468083] Modules linked in: [ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ #56 [ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000 [ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be [ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246 [ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX: 00000000000002df [ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff821f7020 [ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09: 0000000000000000 [ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12: ff006d75646d7564 [ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15: ffff88005b403c00 [ 3929.471869] FS: 00007f0b70480740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000 [ 3929.472286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4: 00000000000406e0 [ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3929.474873] Call Trace: [ 3929.475337] ? kstrdup_const+0x23/0x25 [ 3929.475863] kstrdup+0x2e/0x4b [ 3929.476338] kstrdup_const+0x23/0x25 [ 3929.478084] __kernfs_new_node+0x28/0xbc [ 3929.478478] kernfs_new_node+0x35/0x55 [ 3929.478929] kernfs_create_link+0x23/0x76 [ 3929.479478] sysfs_do_create_link_sd.isra.2+0x85/0xd7 [ 3929.480096] sysfs_create_link+0x33/0x35 [ 3929.480649] device_add+0x200/0x589 [ 3929.481184] netdev_register_kobject+0x7c/0x12f [ 3929.481711] register_netdevice+0x373/0x471 [ 3929.482174] rtnl_newlink+0x614/0x729 [ 3929.482610] ? rtnl_newlink+0x17f/0x729 [ 3929.483080] rtnetlink_rcv_msg+0x188/0x197 [ 3929.483533] ? rcu_read_unlock+0x3e/0x5f [ 3929.483984] ? rtnl_newlink+0x729/0x729 [ 3929.484420] netlink_rcv_skb+0x6c/0xce [ 3929.484858] rtnetlink_rcv+0x23/0x2a [ 3929.485291] netlink_unicast+0x103/0x181 [ 3929.485735] netlink_sendmsg+0x326/0x337 [ 3929.486181] sock_sendmsg_nosec+0x14/0x3f [ 3929.486614] sock_sendmsg+0x29/0x2e [ 3929.486973] ___sys_sendmsg+0x209/0x28b [ 3929.487340] ? do_raw_spin_unlock+0xcd/0xf8 [ 3929.487719] ? _raw_spin_unlock+0x27/0x31 [ 3929.488092] ? __handle_mm_fault+0x651/0xdb1 [ 3929.488471] ? check_chain_key+0xb0/0xfd [ 3929.488847] __sys_sendmsg+0x45/0x63 [ 3929.489206] ? __sys_sendmsg+0x45/0x63 [ 3929.489576] SyS_sendmsg+0x19/0x1b [ 3929.489901] entry_SYSCALL_64_fastpath+0x23/0xc2 [ 3929.490172] RIP: 0033:0x7f0b6fb93690 [ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f0b6fb93690 [ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI: 0000000000000003 [ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09: 0000000000000000 [ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12: 0000000000000002 [ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15: 0000000000000000 [ 3929.492352] ? trace_hardirqs_off_caller+0xa7/0xcf [ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44 89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d 8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01 [ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP: ffff88005872f6a0 Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Fixes: f07d1501292b ("multiq: Further multiqueue cleanup") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: delete now-unused 'err' variable] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit e89d469e3be3ed3d7124a803211a463ff83d0964 upstream.

The below commit added a call to ->destroy() on init failure, but multiq
still frees ->queues on error in init, but ->queues is also freed by
->destroy() thus we get double free and corrupted memory.

Very easy to reproduce (eth0 not multiqueue):
$ tc qdisc add dev eth0 root multiq
RTNETLINK answers: Operation not supported
$ ip l add dumdum type dummy
(crash)

Trace log:
[ 3929.467747] general protection fault: 0000 [#1] SMP
[ 3929.468083] Modules linked in:
[ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ #56
[ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000
[ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be
[ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246
[ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX: 00000000000002df
[ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff821f7020
[ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09: 0000000000000000
[ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12: ff006d75646d7564
[ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15: ffff88005b403c00
[ 3929.471869] FS:  00007f0b70480740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 3929.472286] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4: 00000000000406e0
[ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 3929.474873] Call Trace:
[ 3929.475337]  ? kstrdup_const+0x23/0x25
[ 3929.475863]  kstrdup+0x2e/0x4b
[ 3929.476338]  kstrdup_const+0x23/0x25
[ 3929.478084]  __kernfs_new_node+0x28/0xbc
[ 3929.478478]  kernfs_new_node+0x35/0x55
[ 3929.478929]  kernfs_create_link+0x23/0x76
[ 3929.479478]  sysfs_do_create_link_sd.isra.2+0x85/0xd7
[ 3929.480096]  sysfs_create_link+0x33/0x35
[ 3929.480649]  device_add+0x200/0x589
[ 3929.481184]  netdev_register_kobject+0x7c/0x12f
[ 3929.481711]  register_netdevice+0x373/0x471
[ 3929.482174]  rtnl_newlink+0x614/0x729
[ 3929.482610]  ? rtnl_newlink+0x17f/0x729
[ 3929.483080]  rtnetlink_rcv_msg+0x188/0x197
[ 3929.483533]  ? rcu_read_unlock+0x3e/0x5f
[ 3929.483984]  ? rtnl_newlink+0x729/0x729
[ 3929.484420]  netlink_rcv_skb+0x6c/0xce
[ 3929.484858]  rtnetlink_rcv+0x23/0x2a
[ 3929.485291]  netlink_unicast+0x103/0x181
[ 3929.485735]  netlink_sendmsg+0x326/0x337
[ 3929.486181]  sock_sendmsg_nosec+0x14/0x3f
[ 3929.486614]  sock_sendmsg+0x29/0x2e
[ 3929.486973]  ___sys_sendmsg+0x209/0x28b
[ 3929.487340]  ? do_raw_spin_unlock+0xcd/0xf8
[ 3929.487719]  ? _raw_spin_unlock+0x27/0x31
[ 3929.488092]  ? __handle_mm_fault+0x651/0xdb1
[ 3929.488471]  ? check_chain_key+0xb0/0xfd
[ 3929.488847]  __sys_sendmsg+0x45/0x63
[ 3929.489206]  ? __sys_sendmsg+0x45/0x63
[ 3929.489576]  SyS_sendmsg+0x19/0x1b
[ 3929.489901]  entry_SYSCALL_64_fastpath+0x23/0xc2
[ 3929.490172] RIP: 0033:0x7f0b6fb93690
[ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f0b6fb93690
[ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI: 0000000000000003
[ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09: 0000000000000000
[ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12: 0000000000000002
[ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15: 0000000000000000
[ 3929.492352]  ? trace_hardirqs_off_caller+0xa7/0xcf
[ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44
89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d
8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01
[ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP: ffff88005872f6a0

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: f07d1501292b ("multiq: Further multiqueue cleanup")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: delete now-unused 'err' variable]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_htb: fix crash on init failure 2017-11-11T13:34:36+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2017-08-30T09:48:57+00:00 dba1fd9993877e4a8ea0f2e8059d4140c7dcc0b6 commit 88c2ace69dbef696edba77712882af03879abc9c upstream. The commit below added a call to the ->destroy() callback for all qdiscs which failed in their ->init(), but some were not prepared for such change and can't handle partially initialized qdisc. HTB is one of them and if any error occurs before the qdisc watchdog timer and qdisc work are initialized then we can hit either a null ptr deref (timer->base) when canceling in ->destroy or lockdep error info about trying to register a non-static key and a stack dump. So to fix these two move the watchdog timer and workqueue init before anything that can err out. To reproduce userspace needs to send broken htb qdisc create request, tested with a modified tc (q_htb.c). Trace log: [ 2710.897602] BUG: unable to handle kernel NULL pointer dereference at (null) [ 2710.897977] IP: hrtimer_active+0x17/0x8a [ 2710.898174] PGD 58fab067 [ 2710.898175] P4D 58fab067 [ 2710.898353] PUD 586c0067 [ 2710.898531] PMD 0 [ 2710.898710] [ 2710.899045] Oops: 0000 [#1] SMP [ 2710.899232] Modules linked in: [ 2710.899419] CPU: 1 PID: 950 Comm: tc Not tainted 4.13.0-rc6+ #54 [ 2710.899646] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 2710.900035] task: ffff880059ed2700 task.stack: ffff88005ad4c000 [ 2710.900262] RIP: 0010:hrtimer_active+0x17/0x8a [ 2710.900467] RSP: 0018:ffff88005ad4f960 EFLAGS: 00010246 [ 2710.900684] RAX: 0000000000000000 RBX: ffff88003701e298 RCX: 0000000000000000 [ 2710.900933] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003701e298 [ 2710.901177] RBP: ffff88005ad4f980 R08: 0000000000000001 R09: 0000000000000001 [ 2710.901419] R10: ffff88005ad4f800 R11: 0000000000000400 R12: 0000000000000000 [ 2710.901663] R13: ffff88003701e298 R14: ffffffff822a4540 R15: ffff88005ad4fac0 [ 2710.901907] FS: 00007f2f5e90f740(0000) GS:ffff88005d880000(0000) knlGS:0000000000000000 [ 2710.902277] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2710.902500] CR2: 0000000000000000 CR3: 0000000058ca3000 CR4: 00000000000406e0 [ 2710.902744] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2710.902977] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2710.903180] Call Trace: [ 2710.903332] hrtimer_try_to_cancel+0x1a/0x93 [ 2710.903504] hrtimer_cancel+0x15/0x20 [ 2710.903667] qdisc_watchdog_cancel+0x12/0x14 [ 2710.903866] htb_destroy+0x2e/0xf7 [ 2710.904097] qdisc_create+0x377/0x3fd [ 2710.904330] tc_modify_qdisc+0x4d2/0x4fd [ 2710.904511] rtnetlink_rcv_msg+0x188/0x197 [ 2710.904682] ? rcu_read_unlock+0x3e/0x5f [ 2710.904849] ? rtnl_newlink+0x729/0x729 [ 2710.905017] netlink_rcv_skb+0x6c/0xce [ 2710.905183] rtnetlink_rcv+0x23/0x2a [ 2710.905345] netlink_unicast+0x103/0x181 [ 2710.905511] netlink_sendmsg+0x326/0x337 [ 2710.905679] sock_sendmsg_nosec+0x14/0x3f [ 2710.905847] sock_sendmsg+0x29/0x2e [ 2710.906010] ___sys_sendmsg+0x209/0x28b [ 2710.906176] ? do_raw_spin_unlock+0xcd/0xf8 [ 2710.906346] ? _raw_spin_unlock+0x27/0x31 [ 2710.906514] ? __handle_mm_fault+0x651/0xdb1 [ 2710.906685] ? check_chain_key+0xb0/0xfd [ 2710.906855] __sys_sendmsg+0x45/0x63 [ 2710.907018] ? __sys_sendmsg+0x45/0x63 [ 2710.907185] SyS_sendmsg+0x19/0x1b [ 2710.907344] entry_SYSCALL_64_fastpath+0x23/0xc2 Note that probably this bug goes further back because the default qdisc handling always calls ->destroy on init failure too. Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation") Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 88c2ace69dbef696edba77712882af03879abc9c upstream.

The commit below added a call to the ->destroy() callback for all qdiscs
which failed in their ->init(), but some were not prepared for such
change and can't handle partially initialized qdisc. HTB is one of them
and if any error occurs before the qdisc watchdog timer and qdisc work are
initialized then we can hit either a null ptr deref (timer->base) when
canceling in ->destroy or lockdep error info about trying to register
a non-static key and a stack dump. So to fix these two move the watchdog
timer and workqueue init before anything that can err out.
To reproduce userspace needs to send broken htb qdisc create request,
tested with a modified tc (q_htb.c).

Trace log:
[ 2710.897602] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 2710.897977] IP: hrtimer_active+0x17/0x8a
[ 2710.898174] PGD 58fab067
[ 2710.898175] P4D 58fab067
[ 2710.898353] PUD 586c0067
[ 2710.898531] PMD 0
[ 2710.898710]
[ 2710.899045] Oops: 0000 [#1] SMP
[ 2710.899232] Modules linked in:
[ 2710.899419] CPU: 1 PID: 950 Comm: tc Not tainted 4.13.0-rc6+ #54
[ 2710.899646] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 2710.900035] task: ffff880059ed2700 task.stack: ffff88005ad4c000
[ 2710.900262] RIP: 0010:hrtimer_active+0x17/0x8a
[ 2710.900467] RSP: 0018:ffff88005ad4f960 EFLAGS: 00010246
[ 2710.900684] RAX: 0000000000000000 RBX: ffff88003701e298 RCX: 0000000000000000
[ 2710.900933] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003701e298
[ 2710.901177] RBP: ffff88005ad4f980 R08: 0000000000000001 R09: 0000000000000001
[ 2710.901419] R10: ffff88005ad4f800 R11: 0000000000000400 R12: 0000000000000000
[ 2710.901663] R13: ffff88003701e298 R14: ffffffff822a4540 R15: ffff88005ad4fac0
[ 2710.901907] FS:  00007f2f5e90f740(0000) GS:ffff88005d880000(0000) knlGS:0000000000000000
[ 2710.902277] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2710.902500] CR2: 0000000000000000 CR3: 0000000058ca3000 CR4: 00000000000406e0
[ 2710.902744] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2710.902977] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2710.903180] Call Trace:
[ 2710.903332]  hrtimer_try_to_cancel+0x1a/0x93
[ 2710.903504]  hrtimer_cancel+0x15/0x20
[ 2710.903667]  qdisc_watchdog_cancel+0x12/0x14
[ 2710.903866]  htb_destroy+0x2e/0xf7
[ 2710.904097]  qdisc_create+0x377/0x3fd
[ 2710.904330]  tc_modify_qdisc+0x4d2/0x4fd
[ 2710.904511]  rtnetlink_rcv_msg+0x188/0x197
[ 2710.904682]  ? rcu_read_unlock+0x3e/0x5f
[ 2710.904849]  ? rtnl_newlink+0x729/0x729
[ 2710.905017]  netlink_rcv_skb+0x6c/0xce
[ 2710.905183]  rtnetlink_rcv+0x23/0x2a
[ 2710.905345]  netlink_unicast+0x103/0x181
[ 2710.905511]  netlink_sendmsg+0x326/0x337
[ 2710.905679]  sock_sendmsg_nosec+0x14/0x3f
[ 2710.905847]  sock_sendmsg+0x29/0x2e
[ 2710.906010]  ___sys_sendmsg+0x209/0x28b
[ 2710.906176]  ? do_raw_spin_unlock+0xcd/0xf8
[ 2710.906346]  ? _raw_spin_unlock+0x27/0x31
[ 2710.906514]  ? __handle_mm_fault+0x651/0xdb1
[ 2710.906685]  ? check_chain_key+0xb0/0xfd
[ 2710.906855]  __sys_sendmsg+0x45/0x63
[ 2710.907018]  ? __sys_sendmsg+0x45/0x63
[ 2710.907185]  SyS_sendmsg+0x19/0x1b
[ 2710.907344]  entry_SYSCALL_64_fastpath+0x23/0xc2

Note that probably this bug goes further back because the default qdisc
handling always calls ->destroy on init failure too.

Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net_sched: fix error recovery at qdisc creation 2017-11-11T13:34:36+00:00 Eric Dumazet edumazet@google.com 2017-02-10T18:31:49+00:00 7df9c70f74dcb511381c65334f785fc84c39e5a7 commit 87b60cfacf9f17cf71933c6e33b66e68160af71d upstream. Dmitry reported uses after free in qdisc code [1] The problem here is that ops->init() can return an error. qdisc_create_dflt() then call ops->destroy(), while qdisc_create() does _not_ call it. Four qdisc chose to call their own ops->destroy(), assuming their caller would not. This patch makes sure qdisc_create() calls ops->destroy() and fixes the four qdisc to avoid double free. [1] BUG: KASAN: use-after-free in mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 at addr ffff8801d415d440 Read of size 8 by task syz-executor2/5030 CPU: 0 PID: 5030 Comm: syz-executor2 Not tainted 4.3.5-smp-DEV #119 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000046 ffff8801b435b870 ffffffff81bbbed4 ffff8801db000400 ffff8801d415d440 ffff8801d415dc40 ffff8801c4988510 ffff8801b435b898 ffffffff816682b1 ffff8801b435b928 ffff8801d415d440 ffff8801c49880c0 Call Trace: [<ffffffff81bbbed4>] __dump_stack lib/dump_stack.c:15 [inline] [<ffffffff81bbbed4>] dump_stack+0x6c/0x98 lib/dump_stack.c:51 [<ffffffff816682b1>] kasan_object_err+0x21/0x70 mm/kasan/report.c:158 [<ffffffff81668524>] print_address_description mm/kasan/report.c:196 [inline] [<ffffffff81668524>] kasan_report_error+0x1b4/0x4b0 mm/kasan/report.c:285 [<ffffffff81668953>] kasan_report mm/kasan/report.c:305 [inline] [<ffffffff81668953>] __asan_report_load8_noabort+0x43/0x50 mm/kasan/report.c:326 [<ffffffff82527b02>] mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 [<ffffffff82524bdd>] qdisc_destroy+0x12d/0x290 net/sched/sch_generic.c:953 [<ffffffff82524e30>] qdisc_create_dflt+0xf0/0x120 net/sched/sch_generic.c:848 [<ffffffff8252550d>] attach_default_qdiscs net/sched/sch_generic.c:1029 [inline] [<ffffffff8252550d>] dev_activate+0x6ad/0x880 net/sched/sch_generic.c:1064 [<ffffffff824b1db1>] __dev_open+0x221/0x320 net/core/dev.c:1403 [<ffffffff824b24ce>] __dev_change_flags+0x15e/0x3e0 net/core/dev.c:6858 [<ffffffff824b27de>] dev_change_flags+0x8e/0x140 net/core/dev.c:6926 [<ffffffff824f5bf6>] dev_ifsioc+0x446/0x890 net/core/dev_ioctl.c:260 [<ffffffff824f61fa>] dev_ioctl+0x1ba/0xb80 net/core/dev_ioctl.c:546 [<ffffffff82430509>] sock_do_ioctl+0x99/0xb0 net/socket.c:879 [<ffffffff82430d30>] sock_ioctl+0x2a0/0x390 net/socket.c:958 [<ffffffff816f3b68>] vfs_ioctl fs/ioctl.c:44 [inline] [<ffffffff816f3b68>] do_vfs_ioctl+0x8a8/0xe50 fs/ioctl.c:611 [<ffffffff816f41a4>] SYSC_ioctl fs/ioctl.c:626 [inline] [<ffffffff816f41a4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:617 [<ffffffff8123e357>] entry_SYSCALL_64_fastpath+0x12/0x17 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: - Drop changes to sch_hhf (doesn't exist) and sch_sfq (doesn't have this bug) - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 87b60cfacf9f17cf71933c6e33b66e68160af71d upstream.

Dmitry reported uses after free in qdisc code [1]

The problem here is that ops->init() can return an error.

qdisc_create_dflt() then call ops->destroy(),
while qdisc_create() does _not_ call it.

Four qdisc chose to call their own ops->destroy(), assuming their caller
would not.

This patch makes sure qdisc_create() calls ops->destroy()
and fixes the four qdisc to avoid double free.

[1]
BUG: KASAN: use-after-free in mq_destroy+0x242/0x290 net/sched/sch_mq.c:33 at addr ffff8801d415d440
Read of size 8 by task syz-executor2/5030
CPU: 0 PID: 5030 Comm: syz-executor2 Not tainted 4.3.5-smp-DEV #119
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000046 ffff8801b435b870 ffffffff81bbbed4 ffff8801db000400
 ffff8801d415d440 ffff8801d415dc40 ffff8801c4988510 ffff8801b435b898
 ffffffff816682b1 ffff8801b435b928 ffff8801d415d440 ffff8801c49880c0
Call Trace:
 [<ffffffff81bbbed4>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81bbbed4>] dump_stack+0x6c/0x98 lib/dump_stack.c:51
 [<ffffffff816682b1>] kasan_object_err+0x21/0x70 mm/kasan/report.c:158
 [<ffffffff81668524>] print_address_description mm/kasan/report.c:196 [inline]
 [<ffffffff81668524>] kasan_report_error+0x1b4/0x4b0 mm/kasan/report.c:285
 [<ffffffff81668953>] kasan_report mm/kasan/report.c:305 [inline]
 [<ffffffff81668953>] __asan_report_load8_noabort+0x43/0x50 mm/kasan/report.c:326
 [<ffffffff82527b02>] mq_destroy+0x242/0x290 net/sched/sch_mq.c:33
 [<ffffffff82524bdd>] qdisc_destroy+0x12d/0x290 net/sched/sch_generic.c:953
 [<ffffffff82524e30>] qdisc_create_dflt+0xf0/0x120 net/sched/sch_generic.c:848
 [<ffffffff8252550d>] attach_default_qdiscs net/sched/sch_generic.c:1029 [inline]
 [<ffffffff8252550d>] dev_activate+0x6ad/0x880 net/sched/sch_generic.c:1064
 [<ffffffff824b1db1>] __dev_open+0x221/0x320 net/core/dev.c:1403
 [<ffffffff824b24ce>] __dev_change_flags+0x15e/0x3e0 net/core/dev.c:6858
 [<ffffffff824b27de>] dev_change_flags+0x8e/0x140 net/core/dev.c:6926
 [<ffffffff824f5bf6>] dev_ifsioc+0x446/0x890 net/core/dev_ioctl.c:260
 [<ffffffff824f61fa>] dev_ioctl+0x1ba/0xb80 net/core/dev_ioctl.c:546
 [<ffffffff82430509>] sock_do_ioctl+0x99/0xb0 net/socket.c:879
 [<ffffffff82430d30>] sock_ioctl+0x2a0/0x390 net/socket.c:958
 [<ffffffff816f3b68>] vfs_ioctl fs/ioctl.c:44 [inline]
 [<ffffffff816f3b68>] do_vfs_ioctl+0x8a8/0xe50 fs/ioctl.c:611
 [<ffffffff816f41a4>] SYSC_ioctl fs/ioctl.c:626 [inline]
 [<ffffffff816f41a4>] SyS_ioctl+0x94/0xc0 fs/ioctl.c:617
 [<ffffffff8123e357>] entry_SYSCALL_64_fastpath+0x12/0x17

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2:
 - Drop changes to sch_hhf (doesn't exist) and sch_sfq (doesn't have this bug)
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net sched filters: fix notification of filter delete with proper handle 2017-10-12T14:27:21+00:00 Jamal Hadi Salim jhs@mojatatu.com 2016-10-25T00:18:27+00:00 7b73b4b97fc6d0c37c76baee966ea9b9a6323a72 [ Upstream commit 9ee7837449b3d6f0fcf9132c6b5e5aaa58cc67d4 ] Daniel says: While trying out [1][2], I noticed that tc monitor doesn't show the correct handle on delete: $ tc monitor qdisc clsact ffff: dev eno1 parent ffff:fff1 filter dev eno1 ingress protocol all pref 49152 bpf handle 0x2a [...] deleted filter dev eno1 ingress protocol all pref 49152 bpf handle 0xf3be0c80 some context to explain the above: The user identity of any tc filter is represented by a 32-bit identifier encoded in tcm->tcm_handle. Example 0x2a in the bpf filter above. A user wishing to delete, get or even modify a specific filter uses this handle to reference it. Every classifier is free to provide its own semantics for the 32 bit handle. Example: classifiers like u32 use schemes like 800:1:801 to describe the semantics of their filters represented as hash table, bucket and node ids etc. Classifiers also have internal per-filter representation which is different from this externally visible identity. Most classifiers set this internal representation to be a pointer address (which allows fast retrieval of said filters in their implementations). This internal representation is referenced with the "fh" variable in the kernel control code. When a user successfuly deletes a specific filter, by specifying the correct tcm->tcm_handle, an event is generated to user space which indicates which specific filter was deleted. Before this patch, the "fh" value was sent to user space as the identity. As an example what is shown in the sample bpf filter delete event above is 0xf3be0c80. This is infact a 32-bit truncation of 0xffff8807f3be0c80 which happens to be a 64-bit memory address of the internal filter representation (address of the corresponding filter's struct cls_bpf_prog); After this patch the appropriate user identifiable handle as encoded in the originating request tcm->tcm_handle is generated in the event. One of the cardinal rules of netlink rules is to be able to take an event (such as a delete in this case) and reflect it back to the kernel and successfully delete the filter. This patch achieves that. Note, this issue has existed since the original TC action infrastructure code patch back in 2004 as found in: https://git.kernel.org/cgit/linux/kernel/git/history/history.git/commit/ [1] http://patchwork.ozlabs.org/patch/682828/ [2] http://patchwork.ozlabs.org/patch/682829/ Fixes: 4e54c4816bfe ("[NET]: Add tc extensions infrastructure.") Reported-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
[ Upstream commit 9ee7837449b3d6f0fcf9132c6b5e5aaa58cc67d4 ]

Daniel says:

While trying out [1][2], I noticed that tc monitor doesn't show the
correct handle on delete:

$ tc monitor
qdisc clsact ffff: dev eno1 parent ffff:fff1
filter dev eno1 ingress protocol all pref 49152 bpf handle 0x2a [...]
deleted filter dev eno1 ingress protocol all pref 49152 bpf handle 0xf3be0c80

some context to explain the above:
The user identity of any tc filter is represented by a 32-bit
identifier encoded in tcm->tcm_handle. Example 0x2a in the bpf filter
above. A user wishing to delete, get or even modify a specific filter
uses this handle to reference it.
Every classifier is free to provide its own semantics for the 32 bit handle.
Example: classifiers like u32 use schemes like 800:1:801 to describe
the semantics of their filters represented as hash table, bucket and
node ids etc.
Classifiers also have internal per-filter representation which is different
from this externally visible identity. Most classifiers set this
internal representation to be a pointer address (which allows fast retrieval
of said filters in their implementations). This internal representation
is referenced with the "fh" variable in the kernel control code.

When a user successfuly deletes a specific filter, by specifying the correct
tcm->tcm_handle, an event is generated to user space which indicates
which specific filter was deleted.

Before this patch, the "fh" value was sent to user space as the identity.
As an example what is shown in the sample bpf filter delete event above
is 0xf3be0c80. This is infact a 32-bit truncation of 0xffff8807f3be0c80
which happens to be a 64-bit memory address of the internal filter
representation (address of the corresponding filter's struct cls_bpf_prog);

After this patch the appropriate user identifiable handle as encoded
in the originating request tcm->tcm_handle is generated in the event.
One of the cardinal rules of netlink rules is to be able to take an
event (such as a delete in this case) and reflect it back to the
kernel and successfully delete the filter. This patch achieves that.

Note, this issue has existed since the original TC action
infrastructure code patch back in 2004 as found in:
https://git.kernel.org/cgit/linux/kernel/git/history/history.git/commit/

[1] http://patchwork.ozlabs.org/patch/682828/
[2] http://patchwork.ozlabs.org/patch/682829/

Fixes: 4e54c4816bfe ("[NET]: Add tc extensions infrastructure.")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sch_dsmark: fix invalid skb_cow() usage 2017-07-18T17:38:36+00:00 Eric Dumazet edumazet@google.com 2017-03-17T15:05:28+00:00 d940902921d277f53338dddd5068840893e9b372 commit aea92fb2e09e29653b023d4254ac9fbf94221538 upstream. skb_cow(skb, sizeof(ip header)) is not very helpful in this context. First we need to use pskb_may_pull() to make sure the ip header is in skb linear part, then use skb_try_make_writable() to address clones issues. Fixes: 4c30719f4f55 ("[PKT_SCHED] dsmark: handle cloned and non-linear skb's") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit aea92fb2e09e29653b023d4254ac9fbf94221538 upstream.

skb_cow(skb, sizeof(ip header)) is not very helpful in this context.

First we need to use pskb_may_pull() to make sure the ip header
is in skb linear part, then use skb_try_make_writable() to
address clones issues.

Fixes: 4c30719f4f55 ("[PKT_SCHED] dsmark: handle cloned and non-linear skb's")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>