diff options
| author |   Jason Gunthorpe <jgg@nvidia.com> | 2020-08-18 15:05:20 +0300 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2020-08-27 08:38:15 -0300 |
| commit | 09e328e47a695b0d346598f5d6593ee598e64885 (patch) | |
| tree | 635c7de0cf2fb35f54c7661ef204ffd90dc99208 /drivers | |
| parent | RDMA/ucma: Do not use file->mut to lock destroying (diff) | |
| download | linux-dev-09e328e47a695b0d346598f5d6593ee598e64885.tar.xz linux-dev-09e328e47a695b0d346598f5d6593ee598e64885.zip | |
RDMA/ucma: Fix the locking of ctx->file
ctx->file is changed under the file->mut lock by ucma_migrate_id(), which
is impossible to lock correctly. Instead change ctx->file under the
handler_lock and ctx_table lock and revise all places touching ctx->file
to use this locking when reading ctx->file.
Link: https://lore.kernel.org/r/20200818120526.702120-9-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/infiniband/core/ucma.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index 18285941aec3..f7ec71225e87 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -547,6 +547,7 @@ static void ucma_cleanup_mc_events(struct ucma_multicast *mc) { struct ucma_event *uevent, *tmp; + rdma_lock_handler(mc->ctx->cm_id); mutex_lock(&mc->ctx->file->mut); list_for_each_entry_safe(uevent, tmp, &mc->ctx->file->event_list, list) { if (uevent->mc != mc) @@ -556,6 +557,7 @@ static void ucma_cleanup_mc_events(struct ucma_multicast *mc) kfree(uevent); } mutex_unlock(&mc->ctx->file->mut); + rdma_unlock_handler(mc->ctx->cm_id); } /* @@ -1600,7 +1602,7 @@ static ssize_t ucma_leave_multicast(struct ucma_file *file, mc = xa_load(&multicast_table, cmd.id); if (!mc) mc = ERR_PTR(-ENOENT); - else if (mc->ctx->file != file) + else if (READ_ONCE(mc->ctx->file) != file) mc = ERR_PTR(-EINVAL); else if (!refcount_inc_not_zero(&mc->ctx->ref)) mc = ERR_PTR(-ENXIO); @@ -1692,6 +1694,7 @@ static ssize_t ucma_migrate_id(struct ucma_file *new_file, goto file_put; } + rdma_lock_handler(ctx->cm_id); cur_file = ctx->file; if (cur_file == new_file) { resp.events_reported = ctx->events_reported; @@ -1718,6 +1721,7 @@ response: &resp, sizeof(resp))) ret = -EFAULT; + rdma_unlock_handler(ctx->cm_id); ucma_put_ctx(ctx); file_put: fdput(f); |