diff options
| author | Xin Long <lucien.xin@gmail.com> | 2023-02-22 20:07:21 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-11 18:44:11 +0300 |
| commit | cec326443f01283ef68ea00c06ea073b1835a562 (patch) | |
| tree | d01dba7b69c7aa7a9ae9cc2220b20039b650c6f4 /include/net | |
| parent | aba298b35619213ca787d08d472049627d8cd012 (diff) | |
| download | linux-cec326443f01283ef68ea00c06ea073b1835a562.tar.xz | |
sctp: add a refcnt in sctp_stream_priorities to avoid a nested loop
[ Upstream commit 68ba44639537de6f91fe32783766322d41848127 ]
With this refcnt added in sctp_stream_priorities, we don't need to
traverse all streams to check if the prio is used by other streams
when freeing one stream's prio in sctp_sched_prio_free_sid(). This
can avoid a nested loop (up to 65535 * 65535), which may cause a
stuck as Ying reported:
watchdog: BUG: soft lockup - CPU#23 stuck for 26s! [ksoftirqd/23:136]
Call Trace:
<TASK>
sctp_sched_prio_free_sid+0xab/0x100 [sctp]
sctp_stream_free_ext+0x64/0xa0 [sctp]
sctp_stream_free+0x31/0x50 [sctp]
sctp_association_free+0xa5/0x200 [sctp]
Note that it doesn't need to use refcount_t type for this counter,
as its accessing is always protected under the sock lock.
v1->v2:
- add a check in sctp_sched_prio_set to avoid the possible prio_head
refcnt overflow.
Fixes: 9ed7bfc79542 ("sctp: fix memory leak in sctp_stream_outq_migrate()")
Reported-by: Ying Xu <yinxu@redhat.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/825eb0c905cb864991eba335f4a2b780e543f06b.1677085641.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/sctp/structs.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index cb05e503c9cd..48cbf3352042 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -1400,6 +1400,7 @@ struct sctp_stream_priorities { /* The next stream stream in line */ struct sctp_stream_out_ext *next; __u16 prio; + __u16 users; }; struct sctp_stream_out_ext { |