Re: [PATCH] io_uring: fix file leak on creating io ctx

[Jens Axboe]

On 12/7/20 1:15 AM, Hillf Danton wrote:
> Put file as part of error handling when setting up io ctx to fix
> memory leak like the following one.
> 
>    BUG: memory leak
>    unreferenced object 0xffff888101ea2200 (size 256):
>      comm "syz-executor355", pid 8470, jiffies 4294953658 (age 32.400s)
>      hex dump (first 32 bytes):
>        00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>        20 59 03 01 81 88 ff ff 80 87 a8 10 81 88 ff ff   Y..............
>      backtrace:
>        [<000000002e0a7c5f>] kmem_cache_zalloc include/linux/slab.h:654 [inline]
>        [<000000002e0a7c5f>] __alloc_file+0x1f/0x130 fs/file_table.c:101
>        [<000000001a55b73a>] alloc_empty_file+0x69/0x120 fs/file_table.c:151
>        [<00000000fb22349e>] alloc_file+0x33/0x1b0 fs/file_table.c:193
>        [<000000006e1465bb>] alloc_file_pseudo+0xb2/0x140 fs/file_table.c:233
>        [<000000007118092a>] anon_inode_getfile fs/anon_inodes.c:91 [inline]
>        [<000000007118092a>] anon_inode_getfile+0xaa/0x120 fs/anon_inodes.c:74
>        [<000000002ae99012>] io_uring_get_fd fs/io_uring.c:9198 [inline]
>        [<000000002ae99012>] io_uring_create fs/io_uring.c:9377 [inline]
>        [<000000002ae99012>] io_uring_setup+0x1125/0x1630 fs/io_uring.c:9411
>        [<000000008280baad>] do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
>        [<00000000685d8cf0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Applied for 5.10, thanks.

-- 
Jens Axboe