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| author | Rafael Mendonca <rafaelmendsr@gmail.com> | 2022-10-20 04:47:09 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-10-20 15:48:59 +0300 |
| commit | 996d3efeb091c503afd3ee6b5e20eabf446fd955 (patch) | |
| tree | 187f45814eade85a8548fb61e20eda6652344bf1 | |
| parent | 16bbdfe5fb0e78e0acb13e45fc127e9a296913f2 (diff) | |
| download | linux-996d3efeb091c503afd3ee6b5e20eabf446fd955.tar.xz | |
io-wq: Fix memory leak in worker creation
If the CPU mask allocation for a node fails, then the memory allocated for
the 'io_wqe' struct of the current node doesn't get freed on the error
handling path, since it has not yet been added to the 'wqes' array.
This was spotted when fuzzing v6.1-rc1 with Syzkaller:
BUG: memory leak
unreferenced object 0xffff8880093d5000 (size 1024):
comm "syz-executor.2", pid 7701, jiffies 4295048595 (age 13.900s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000cb463369>] __kmem_cache_alloc_node+0x18e/0x720
[<00000000147a3f9c>] kmalloc_node_trace+0x2a/0x130
[<000000004e107011>] io_wq_create+0x7b9/0xdc0
[<00000000c38b2018>] io_uring_alloc_task_context+0x31e/0x59d
[<00000000867399da>] __io_uring_add_tctx_node.cold+0x19/0x1ba
[<000000007e0e7a79>] io_uring_setup.cold+0x1b80/0x1dce
[<00000000b545e9f6>] __x64_sys_io_uring_setup+0x5d/0x80
[<000000008a8a7508>] do_syscall_64+0x5d/0x90
[<000000004ac08bec>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: 0e03496d1967 ("io-wq: use private CPU mask")
Cc: stable@vger.kernel.org
Signed-off-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Link: https://lore.kernel.org/r/20221020014710.902201-1-rafaelmendsr@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | io_uring/io-wq.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c index c6536d4b2da0..6f1d0e5df23a 100644 --- a/io_uring/io-wq.c +++ b/io_uring/io-wq.c @@ -1164,10 +1164,10 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node); if (!wqe) goto err; + wq->wqes[node] = wqe; if (!alloc_cpumask_var(&wqe->cpu_mask, GFP_KERNEL)) goto err; cpumask_copy(wqe->cpu_mask, cpumask_of_node(node)); - wq->wqes[node] = wqe; wqe->node = alloc_node; wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded; wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = |