| Message ID | 20221018063201.306474-3-shaozhengchao@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f5ffa3b1197395501b72c10b35518bf58ef24475 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | fix null pointer access issue in qdisc | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Clearly marked for net |
| netdev/fixes_present | success | Fixes tag present in non-next series |
| netdev/subject_prefix | success | Link |
| netdev/cover_letter | success | Series has a cover letter |
| netdev/patch_count | success | Link |
| netdev/header_inline | success | No static functions without inline keyword in header files |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/cc_maintainers | success | CCed 8 of 8 maintainers |
| netdev/build_clang | success | Errors and warnings before: 0 this patch: 0 |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Signed-off-by tag matches author and committer |
| netdev/check_selftest | success | No net selftest shell script |
| netdev/verify_fixes | success | No Fixes tag |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 47 lines checked |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/source_inline | success | Was 0 now: 0 |
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c index 99d318b60568..8c4fee063436 100644 --- a/net/sched/sch_fq_codel.c +++ b/net/sched/sch_fq_codel.c @@ -478,24 +478,26 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt, if (opt) { err = fq_codel_change(sch, opt, extack); if (err) - return err; + goto init_failure; } err = tcf_block_get(&q->block, &q->filter_list, sch, extack); if (err) - return err; + goto init_failure; if (!q->flows) { q->flows = kvcalloc(q->flows_cnt, sizeof(struct fq_codel_flow), GFP_KERNEL); - if (!q->flows) - return -ENOMEM; - + if (!q->flows) { + err = -ENOMEM; + goto init_failure; + } q->backlogs = kvcalloc(q->flows_cnt, sizeof(u32), GFP_KERNEL); - if (!q->backlogs) - return -ENOMEM; - + if (!q->backlogs) { + err = -ENOMEM; + goto alloc_failure; + } for (i = 0; i < q->flows_cnt; i++) { struct fq_codel_flow *flow = q->flows + i; @@ -508,6 +510,13 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt, else sch->flags &= ~TCQ_F_CAN_BYPASS; return 0; + +alloc_failure: + kvfree(q->flows); + q->flows = NULL; +init_failure: + q->flows_cnt = 0; + return err; } static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
This reverts commit 494f5063b86cd6e972cb41a27e083c9a3664319d. When the default qdisc is fq_codel, if the qdisc of dev_queue fails to be inited during mqprio_init(), fq_codel_reset() is invoked to clear resources. In this case, the flow is NULL, and it will cause gpf issue. The process is as follows: qdisc_create_dflt() fq_codel_init() ... q->flows_cnt = 1024; ... q->flows = kvcalloc(...) --->failed, q->flows is NULL ... qdisc_put() ... fq_codel_reset() ... flow = q->flows + i --->q->flows is NULL The following is the Call Trace information: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] RIP: 0010:fq_codel_reset+0x14d/0x350 Call Trace: <TASK> qdisc_reset+0xed/0x6f0 qdisc_destroy+0x82/0x4c0 qdisc_put+0x9e/0xb0 qdisc_create_dflt+0x2c3/0x4a0 mqprio_init+0xa71/0x1760 qdisc_create+0x3eb/0x1000 tc_modify_qdisc+0x408/0x1720 rtnetlink_rcv_msg+0x38e/0xac0 netlink_rcv_skb+0x12d/0x3a0 netlink_unicast+0x4a2/0x740 netlink_sendmsg+0x826/0xcc0 sock_sendmsg+0xc5/0x100 ____sys_sendmsg+0x583/0x690 ___sys_sendmsg+0xe8/0x160 __sys_sendmsg+0xbf/0x160 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fd272b22d04 </TASK> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> --- net/sched/sch_fq_codel.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)