commit: 10685681bafc ("net_sched: sch_sfq: don't allow 1 packet limit") fixes CVE-2024-57996 and commit: b3bf8f63e617 ("net_sched: sch_sfq: move the limit validation") fixes CVE-2025-37752.
Patches 3 and 5 are CVE fixes for above mentioned CVEs. Patch 1,2 and 4 are pulled in as stable-deps.
Testing performed on the patched 5.10.238 kernel with the above 5 patches: (Used latest upstream kselftests for tc-testing)
# uname -a Linux hamogala-vm-6 5.10.238+ #2 SMP Sun Jun 15 17:27:54 GMT 2025 x86_64 x86_64 x86_64 GNU/Linux # ./tdc.py -f tc-tests/qdiscs/sfq.json -- ns/SubPlugin.__init__ Test 7482: Create SFQ with default setting Test c186: Create SFQ with limit setting Test ae23: Create SFQ with perturb setting Test a430: Create SFQ with quantum setting Test 4539: Create SFQ with divisor setting Test b089: Create SFQ with flows setting Test 99a0: Create SFQ with depth setting Test 7389: Create SFQ with headdrop setting Test 6472: Create SFQ with redflowlimit setting Test 8929: Show SFQ class Test 4d6f: Check that limit of 1 is rejected Test 7f8f: Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1) Test 5168: Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
All test results:
1..13 ok 1 7482 - Create SFQ with default setting ok 2 c186 - Create SFQ with limit setting ok 3 ae23 - Create SFQ with perturb setting ok 4 a430 - Create SFQ with quantum setting ok 5 4539 - Create SFQ with divisor setting ok 6 b089 - Create SFQ with flows setting ok 7 99a0 - Create SFQ with depth setting ok 8 7389 - Create SFQ with headdrop setting ok 9 6472 - Create SFQ with redflowlimit setting ok 10 8929 - Show SFQ class ok 11 4d6f - Check that limit of 1 is rejected ok 12 7f8f - Check that a derived limit of 1 is rejected (limit 2 depth 1 flows 1) ok 13 5168 - Check that a derived limit of 1 is rejected (limit 2 depth 1 divisor 1)
Thanks, Harshit
Eric Dumazet (2): net_sched: sch_sfq: annotate data-races around q->perturb_period net_sched: sch_sfq: handle bigger packets
Octavian Purdila (3): net_sched: sch_sfq: don't allow 1 packet limit net_sched: sch_sfq: use a temporary work area for validating configuration net_sched: sch_sfq: move the limit validation
net/sched/sch_sfq.c | 112 ++++++++++++++++++++++++++++---------------- 1 file changed, 71 insertions(+), 41 deletions(-)
From: Eric Dumazet edumazet@google.com
[ Upstream commit a17ef9e6c2c1cf0fc6cd6ca6a9ce525c67d1da7f ]
sfq_perturbation() reads q->perturb_period locklessly. Add annotations to fix potential issues.
Signed-off-by: Eric Dumazet edumazet@google.com Reviewed-by: Simon Horman horms@kernel.org Link: https://lore.kernel.org/r/20240430180015.3111398-1-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org (cherry picked from commit a17ef9e6c2c1cf0fc6cd6ca6a9ce525c67d1da7f) [Harshit: Backport to 5.10.y, conflicts resolved due to missing commit: d636fc5dd692 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping") in 5.10.y] Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- net/sched/sch_sfq.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 066754a18569..4234ca7ac66a 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -608,6 +608,7 @@ static void sfq_perturbation(struct timer_list *t) struct Qdisc *sch = q->sch; spinlock_t *root_lock = qdisc_lock(qdisc_root_sleeping(sch)); siphash_key_t nkey; + int period;
get_random_bytes(&nkey, sizeof(nkey)); spin_lock(root_lock); @@ -616,8 +617,12 @@ static void sfq_perturbation(struct timer_list *t) sfq_rehash(sch); spin_unlock(root_lock);
- if (q->perturb_period) - mod_timer(&q->perturb_timer, jiffies + q->perturb_period); + /* q->perturb_period can change under us from + * sfq_change() and sfq_destroy(). + */ + period = READ_ONCE(q->perturb_period); + if (period) + mod_timer(&q->perturb_timer, jiffies + period); }
static int sfq_change(struct Qdisc *sch, struct nlattr *opt) @@ -659,7 +664,7 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt) q->quantum = ctl->quantum; q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum); } - q->perturb_period = ctl->perturb_period * HZ; + WRITE_ONCE(q->perturb_period, ctl->perturb_period * HZ); if (ctl->flows) q->maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS); if (ctl->divisor) { @@ -721,7 +726,7 @@ static void sfq_destroy(struct Qdisc *sch) struct sfq_sched_data *q = qdisc_priv(sch);
tcf_block_put(q->block); - q->perturb_period = 0; + WRITE_ONCE(q->perturb_period, 0); del_timer_sync(&q->perturb_timer); sfq_free(q->ht); sfq_free(q->slots);
From: Eric Dumazet edumazet@google.com
[ Upstream commit e4650d7ae4252f67e997a632adfae0dd74d3a99a ]
SFQ has an assumption on dealing with packets smaller than 64KB.
Even before BIG TCP, TCA_STAB can provide arbitrary big values in qdisc_pkt_len(skb)
It is time to switch (struct sfq_slot)->allot to a 32bit field.
sizeof(struct sfq_slot) is now 64 bytes, giving better cache locality.
Signed-off-by: Eric Dumazet edumazet@google.com Reviewed-by: Toke Høiland-Jørgensen toke@redhat.com Link: https://patch.msgid.link/20241008111603.653140-1-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org (cherry picked from commit e4650d7ae4252f67e997a632adfae0dd74d3a99a) Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- net/sched/sch_sfq.c | 39 +++++++++++++-------------------------- 1 file changed, 13 insertions(+), 26 deletions(-)
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 4234ca7ac66a..2fb2dcd0ae2a 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -77,12 +77,6 @@ #define SFQ_EMPTY_SLOT 0xffff #define SFQ_DEFAULT_HASH_DIVISOR 1024
-/* We use 16 bits to store allot, and want to handle packets up to 64K - * Scale allot by 8 (1<<3) so that no overflow occurs. - */ -#define SFQ_ALLOT_SHIFT 3 -#define SFQ_ALLOT_SIZE(X) DIV_ROUND_UP(X, 1 << SFQ_ALLOT_SHIFT) - /* This type should contain at least SFQ_MAX_DEPTH + 1 + SFQ_MAX_FLOWS values */ typedef u16 sfq_index;
@@ -104,7 +98,7 @@ struct sfq_slot { sfq_index next; /* next slot in sfq RR chain */ struct sfq_head dep; /* anchor in dep[] chains */ unsigned short hash; /* hash value (index in ht[]) */ - short allot; /* credit for this slot */ + int allot; /* credit for this slot */
unsigned int backlog; struct red_vars vars; @@ -120,7 +114,6 @@ struct sfq_sched_data { siphash_key_t perturbation; u8 cur_depth; /* depth of longest slot */ u8 flags; - unsigned short scaled_quantum; /* SFQ_ALLOT_SIZE(quantum) */ struct tcf_proto __rcu *filter_list; struct tcf_block *block; sfq_index *ht; /* Hash table ('divisor' slots) */ @@ -456,7 +449,7 @@ sfq_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) */ q->tail = slot; /* We could use a bigger initial quantum for new flows */ - slot->allot = q->scaled_quantum; + slot->allot = q->quantum; } if (++sch->q.qlen <= q->limit) return NET_XMIT_SUCCESS; @@ -493,7 +486,7 @@ sfq_dequeue(struct Qdisc *sch) slot = &q->slots[a]; if (slot->allot <= 0) { q->tail = slot; - slot->allot += q->scaled_quantum; + slot->allot += q->quantum; goto next_slot; } skb = slot_dequeue_head(slot); @@ -512,7 +505,7 @@ sfq_dequeue(struct Qdisc *sch) } q->tail->next = next_a; } else { - slot->allot -= SFQ_ALLOT_SIZE(qdisc_pkt_len(skb)); + slot->allot -= qdisc_pkt_len(skb); } return skb; } @@ -595,7 +588,7 @@ static void sfq_rehash(struct Qdisc *sch) q->tail->next = x; } q->tail = slot; - slot->allot = q->scaled_quantum; + slot->allot = q->quantum; } } sch->q.qlen -= dropped; @@ -625,7 +618,8 @@ static void sfq_perturbation(struct timer_list *t) mod_timer(&q->perturb_timer, jiffies + period); }
-static int sfq_change(struct Qdisc *sch, struct nlattr *opt) +static int sfq_change(struct Qdisc *sch, struct nlattr *opt, + struct netlink_ext_ack *extack) { struct sfq_sched_data *q = qdisc_priv(sch); struct tc_sfq_qopt *ctl = nla_data(opt); @@ -643,14 +637,10 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt) (!is_power_of_2(ctl->divisor) || ctl->divisor > 65536)) return -EINVAL;
- /* slot->allot is a short, make sure quantum is not too big. */ - if (ctl->quantum) { - unsigned int scaled = SFQ_ALLOT_SIZE(ctl->quantum); - - if (scaled <= 0 || scaled > SHRT_MAX) - return -EINVAL; + if ((int)ctl->quantum < 0) { + NL_SET_ERR_MSG_MOD(extack, "invalid quantum"); + return -EINVAL; } - if (ctl_v1 && !red_check_params(ctl_v1->qth_min, ctl_v1->qth_max, ctl_v1->Wlog, ctl_v1->Scell_log, NULL)) return -EINVAL; @@ -660,10 +650,8 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt) return -ENOMEM; } sch_tree_lock(sch); - if (ctl->quantum) { + if (ctl->quantum) q->quantum = ctl->quantum; - q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum); - } WRITE_ONCE(q->perturb_period, ctl->perturb_period * HZ); if (ctl->flows) q->maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS); @@ -759,12 +747,11 @@ static int sfq_init(struct Qdisc *sch, struct nlattr *opt, q->divisor = SFQ_DEFAULT_HASH_DIVISOR; q->maxflows = SFQ_DEFAULT_FLOWS; q->quantum = psched_mtu(qdisc_dev(sch)); - q->scaled_quantum = SFQ_ALLOT_SIZE(q->quantum); q->perturb_period = 0; get_random_bytes(&q->perturbation, sizeof(q->perturbation));
if (opt) { - int err = sfq_change(sch, opt); + int err = sfq_change(sch, opt, extack); if (err) return err; } @@ -875,7 +862,7 @@ static int sfq_dump_class_stats(struct Qdisc *sch, unsigned long cl, if (idx != SFQ_EMPTY_SLOT) { const struct sfq_slot *slot = &q->slots[idx];
- xstats.allot = slot->allot << SFQ_ALLOT_SHIFT; + xstats.allot = slot->allot; qs.qlen = slot->qlen; qs.backlog = slot->backlog; }
From: Octavian Purdila tavip@google.com
[ Upstream commit 10685681bafce6febb39770f3387621bf5d67d0b ]
The current implementation does not work correctly with a limit of 1. iproute2 actually checks for this and this patch adds the check in kernel as well.
This fixes the following syzkaller reported crash:
UBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:210:6 index 65535 is out of range for type 'struct sfq_head[128]' CPU: 0 PID: 2569 Comm: syz-executor101 Not tainted 5.10.0-smp-DEV #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x125/0x19f lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:148 [inline] __ubsan_handle_out_of_bounds+0xed/0x120 lib/ubsan.c:347 sfq_link net/sched/sch_sfq.c:210 [inline] sfq_dec+0x528/0x600 net/sched/sch_sfq.c:238 sfq_dequeue+0x39b/0x9d0 net/sched/sch_sfq.c:500 sfq_reset+0x13/0x50 net/sched/sch_sfq.c:525 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 tbf_reset+0x3d/0x100 net/sched/sch_tbf.c:319 qdisc_reset+0xfe/0x510 net/sched/sch_generic.c:1026 dev_reset_queue+0x8c/0x140 net/sched/sch_generic.c:1296 netdev_for_each_tx_queue include/linux/netdevice.h:2350 [inline] dev_deactivate_many+0x6dc/0xc20 net/sched/sch_generic.c:1362 __dev_close_many+0x214/0x350 net/core/dev.c:1468 dev_close_many+0x207/0x510 net/core/dev.c:1506 unregister_netdevice_many+0x40f/0x16b0 net/core/dev.c:10738 unregister_netdevice_queue+0x2be/0x310 net/core/dev.c:10695 unregister_netdevice include/linux/netdevice.h:2893 [inline] __tun_detach+0x6b6/0x1600 drivers/net/tun.c:689 tun_detach drivers/net/tun.c:705 [inline] tun_chr_close+0x104/0x1b0 drivers/net/tun.c:3640 __fput+0x203/0x840 fs/file_table.c:280 task_work_run+0x129/0x1b0 kernel/task_work.c:185 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x5ce/0x2200 kernel/exit.c:931 do_group_exit+0x144/0x310 kernel/exit.c:1046 __do_sys_exit_group kernel/exit.c:1057 [inline] __se_sys_exit_group kernel/exit.c:1055 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1055 do_syscall_64+0x6c/0xd0 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fe5e7b52479 Code: Unable to access opcode bytes at RIP 0x7fe5e7b5244f. RSP: 002b:00007ffd3c800398 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe5e7b52479 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007fe5e7bcd2d0 R08: ffffffffffffffb8 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5e7bcd2d0 R13: 0000000000000000 R14: 00007fe5e7bcdd20 R15: 00007fe5e7b24270
The crash can be also be reproduced with the following (with a tc recompiled to allow for sfq limits of 1):
tc qdisc add dev dummy0 handle 1: root tbf rate 1Kbit burst 100b lat 1s ../iproute2-6.9.0/tc/tc qdisc add dev dummy0 handle 2: parent 1:10 sfq limit 1 ifconfig dummy0 up ping -I dummy0 -f -c2 -W0.1 8.8.8.8 sleep 1
Scenario that triggers the crash:
* the first packet is sent and queued in TBF and SFQ; qdisc qlen is 1
* TBF dequeues: it peeks from SFQ which moves the packet to the gso_skb list and keeps qdisc qlen set to 1. TBF is out of tokens so it schedules itself for later.
* the second packet is sent and TBF tries to queues it to SFQ. qdisc qlen is now 2 and because the SFQ limit is 1 the packet is dropped by SFQ. At this point qlen is 1, and all of the SFQ slots are empty, however q->tail is not NULL.
At this point, assuming no more packets are queued, when sch_dequeue runs again it will decrement the qlen for the current empty slot causing an underflow and the subsequent out of bounds access.
Reported-by: syzbot syzkaller@googlegroups.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Octavian Purdila tavip@google.com Reviewed-by: Eric Dumazet edumazet@google.com Link: https://patch.msgid.link/20241204030520.2084663-2-tavip@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org (cherry picked from commit 10685681bafce6febb39770f3387621bf5d67d0b) Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- net/sched/sch_sfq.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 2fb2dcd0ae2a..16dd1d802e64 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -649,6 +649,10 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt, if (!p) return -ENOMEM; } + if (ctl->limit == 1) { + NL_SET_ERR_MSG_MOD(extack, "invalid limit"); + return -EINVAL; + } sch_tree_lock(sch); if (ctl->quantum) q->quantum = ctl->quantum;
From: Octavian Purdila tavip@google.com
[ Upstream commit 8c0cea59d40cf6dd13c2950437631dd614fbade6 ]
Many configuration parameters have influence on others (e.g. divisor -> flows -> limit, depth -> limit) and so it is difficult to correctly do all of the validation before applying the configuration. And if a validation error is detected late it is difficult to roll back a partially applied configuration.
To avoid these issues use a temporary work area to update and validate the configuration and only then apply the configuration to the internal state.
Signed-off-by: Octavian Purdila tavip@google.com Acked-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: David S. Miller davem@davemloft.net (cherry picked from commit 8c0cea59d40cf6dd13c2950437631dd614fbade6) Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- net/sched/sch_sfq.c | 56 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 44 insertions(+), 12 deletions(-)
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 16dd1d802e64..9a8c9138702a 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -628,6 +628,15 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt, struct red_parms *p = NULL; struct sk_buff *to_free = NULL; struct sk_buff *tail = NULL; + unsigned int maxflows; + unsigned int quantum; + unsigned int divisor; + int perturb_period; + u8 headdrop; + u8 maxdepth; + int limit; + u8 flags; +
if (opt->nla_len < nla_attr_size(sizeof(*ctl))) return -EINVAL; @@ -653,36 +662,59 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt, NL_SET_ERR_MSG_MOD(extack, "invalid limit"); return -EINVAL; } + sch_tree_lock(sch); + + limit = q->limit; + divisor = q->divisor; + headdrop = q->headdrop; + maxdepth = q->maxdepth; + maxflows = q->maxflows; + perturb_period = q->perturb_period; + quantum = q->quantum; + flags = q->flags; + + /* update and validate configuration */ if (ctl->quantum) - q->quantum = ctl->quantum; - WRITE_ONCE(q->perturb_period, ctl->perturb_period * HZ); + quantum = ctl->quantum; + perturb_period = ctl->perturb_period * HZ; if (ctl->flows) - q->maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS); + maxflows = min_t(u32, ctl->flows, SFQ_MAX_FLOWS); if (ctl->divisor) { - q->divisor = ctl->divisor; - q->maxflows = min_t(u32, q->maxflows, q->divisor); + divisor = ctl->divisor; + maxflows = min_t(u32, maxflows, divisor); } if (ctl_v1) { if (ctl_v1->depth) - q->maxdepth = min_t(u32, ctl_v1->depth, SFQ_MAX_DEPTH); + maxdepth = min_t(u32, ctl_v1->depth, SFQ_MAX_DEPTH); if (p) { - swap(q->red_parms, p); - red_set_parms(q->red_parms, + red_set_parms(p, ctl_v1->qth_min, ctl_v1->qth_max, ctl_v1->Wlog, ctl_v1->Plog, ctl_v1->Scell_log, NULL, ctl_v1->max_P); } - q->flags = ctl_v1->flags; - q->headdrop = ctl_v1->headdrop; + flags = ctl_v1->flags; + headdrop = ctl_v1->headdrop; } if (ctl->limit) { - q->limit = min_t(u32, ctl->limit, q->maxdepth * q->maxflows); - q->maxflows = min_t(u32, q->maxflows, q->limit); + limit = min_t(u32, ctl->limit, maxdepth * maxflows); + maxflows = min_t(u32, maxflows, limit); }
+ /* commit configuration */ + q->limit = limit; + q->divisor = divisor; + q->headdrop = headdrop; + q->maxdepth = maxdepth; + q->maxflows = maxflows; + WRITE_ONCE(q->perturb_period, perturb_period); + q->quantum = quantum; + q->flags = flags; + if (p) + swap(q->red_parms, p); + qlen = sch->q.qlen; while (sch->q.qlen > q->limit) { dropped += sfq_drop(sch, &to_free);
From: Octavian Purdila tavip@google.com
[ Upstream commit b3bf8f63e6179076b57c9de660c9f80b5abefe70 ]
It is not sufficient to directly validate the limit on the data that the user passes as it can be updated based on how the other parameters are changed.
Move the check at the end of the configuration update process to also catch scenarios where the limit is indirectly updated, for example with the following configurations:
tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 depth 1 tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 divisor 1
This fixes the following syzkaller reported crash:
------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in net/sched/sch_sfq.c:203:6 index 65535 is out of range for type 'struct sfq_head[128]' CPU: 1 UID: 0 PID: 3037 Comm: syz.2.16 Not tainted 6.14.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x201/0x300 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_out_of_bounds+0xf5/0x120 lib/ubsan.c:429 sfq_link net/sched/sch_sfq.c:203 [inline] sfq_dec+0x53c/0x610 net/sched/sch_sfq.c:231 sfq_dequeue+0x34e/0x8c0 net/sched/sch_sfq.c:493 sfq_reset+0x17/0x60 net/sched/sch_sfq.c:518 qdisc_reset+0x12e/0x600 net/sched/sch_generic.c:1035 tbf_reset+0x41/0x110 net/sched/sch_tbf.c:339 qdisc_reset+0x12e/0x600 net/sched/sch_generic.c:1035 dev_reset_queue+0x100/0x1b0 net/sched/sch_generic.c:1311 netdev_for_each_tx_queue include/linux/netdevice.h:2590 [inline] dev_deactivate_many+0x7e5/0xe70 net/sched/sch_generic.c:1375
Reported-by: syzbot syzkaller@googlegroups.com Fixes: 10685681bafc ("net_sched: sch_sfq: don't allow 1 packet limit") Signed-off-by: Octavian Purdila tavip@google.com Acked-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: David S. Miller davem@davemloft.net (cherry picked from commit b3bf8f63e6179076b57c9de660c9f80b5abefe70) Signed-off-by: Harshit Mogalapalli harshit.m.mogalapalli@oracle.com --- net/sched/sch_sfq.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 9a8c9138702a..ce7d658b7ecb 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -658,10 +658,6 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt, if (!p) return -ENOMEM; } - if (ctl->limit == 1) { - NL_SET_ERR_MSG_MOD(extack, "invalid limit"); - return -EINVAL; - }
sch_tree_lock(sch);
@@ -702,6 +698,12 @@ static int sfq_change(struct Qdisc *sch, struct nlattr *opt, limit = min_t(u32, ctl->limit, maxdepth * maxflows); maxflows = min_t(u32, maxflows, limit); } + if (limit == 1) { + sch_tree_unlock(sch); + kfree(p); + NL_SET_ERR_MSG_MOD(extack, "invalid limit"); + return -EINVAL; + }
/* commit configuration */ q->limit = limit;
linux-stable-mirror@lists.linaro.org
-
Harshit Mogalapalli