linux/io_uring/opdef.c
Breno Leitao e112311615 io_uring/rw: Free iovec before cleaning async data
kmemleak shows that there is a memory leak in io_uring read operation,
where a buffer is allocated at iovec import, but never de-allocated.

The memory is allocated at io_async_rw->free_iovec, but, then
io_async_rw is kfreed, taking the allocated memory with it. I saw this
happening when the read operation fails with -11 (EAGAIN).

This is the kmemleak splat.

    unreferenced object 0xffff8881da591c00 (size 256):
...
      backtrace (crc 7a15bdee):
	[<00000000256f2de4>] __kmalloc+0x2d6/0x410
	[<000000007a9f5fc7>] iovec_from_user.part.0+0xc6/0x160
	[<00000000cecdf83a>] __import_iovec+0x50/0x220
	[<00000000d1d586a2>] __io_import_iovec+0x13d/0x220
	[<0000000054ee9bd2>] io_prep_rw+0x186/0x340
	[<00000000a9c0372d>] io_prep_rwv+0x31/0x120
	[<000000001d1170b9>] io_prep_readv+0xe/0x30
	[<0000000070b8eb67>] io_submit_sqes+0x1bd/0x780
	[<00000000812496d4>] __do_sys_io_uring_enter+0x3ed/0x5b0
	[<0000000081499602>] do_syscall_64+0x5d/0x170
	[<00000000de1c5a4d>] entry_SYSCALL_64_after_hwframe+0x76/0x7e

This occurs because the async data cleanup functions are not set for
read/write operations. As a result, the potentially allocated iovec in
the rw async data is not freed before the async data is released,
leading to a memory leak.

With this following patch, kmemleak does not show the leaked memory
anymore, and all liburing tests pass.

Fixes: a9165b83c1 ("io_uring/rw: always setup io_async_rw for read/write requests")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20240530142340.1248216-1-leitao@debian.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-30 08:33:01 -06:00

742 lines
15 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* io_uring opcode handling table
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/io_uring.h>
#include "io_uring.h"
#include "opdef.h"
#include "refs.h"
#include "tctx.h"
#include "sqpoll.h"
#include "fdinfo.h"
#include "kbuf.h"
#include "rsrc.h"
#include "xattr.h"
#include "nop.h"
#include "fs.h"
#include "splice.h"
#include "sync.h"
#include "advise.h"
#include "openclose.h"
#include "uring_cmd.h"
#include "epoll.h"
#include "statx.h"
#include "net.h"
#include "msg_ring.h"
#include "timeout.h"
#include "poll.h"
#include "cancel.h"
#include "rw.h"
#include "waitid.h"
#include "futex.h"
#include "truncate.h"
static int io_no_issue(struct io_kiocb *req, unsigned int issue_flags)
{
WARN_ON_ONCE(1);
return -ECANCELED;
}
static __maybe_unused int io_eopnotsupp_prep(struct io_kiocb *kiocb,
const struct io_uring_sqe *sqe)
{
return -EOPNOTSUPP;
}
const struct io_issue_def io_issue_defs[] = {
[IORING_OP_NOP] = {
.audit_skip = 1,
.iopoll = 1,
.prep = io_nop_prep,
.issue = io_nop,
},
[IORING_OP_READV] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.buffer_select = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.vectored = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_readv,
.issue = io_read,
},
[IORING_OP_WRITEV] = {
.needs_file = 1,
.hash_reg_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.vectored = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_writev,
.issue = io_write,
},
[IORING_OP_FSYNC] = {
.needs_file = 1,
.audit_skip = 1,
.prep = io_fsync_prep,
.issue = io_fsync,
},
[IORING_OP_READ_FIXED] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_read_fixed,
.issue = io_read,
},
[IORING_OP_WRITE_FIXED] = {
.needs_file = 1,
.hash_reg_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_write_fixed,
.issue = io_write,
},
[IORING_OP_POLL_ADD] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.audit_skip = 1,
.prep = io_poll_add_prep,
.issue = io_poll_add,
},
[IORING_OP_POLL_REMOVE] = {
.audit_skip = 1,
.prep = io_poll_remove_prep,
.issue = io_poll_remove,
},
[IORING_OP_SYNC_FILE_RANGE] = {
.needs_file = 1,
.audit_skip = 1,
.prep = io_sfr_prep,
.issue = io_sync_file_range,
},
[IORING_OP_SENDMSG] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.ioprio = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_sendmsg_prep,
.issue = io_sendmsg,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_RECVMSG] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.buffer_select = 1,
.ioprio = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_recvmsg_prep,
.issue = io_recvmsg,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_TIMEOUT] = {
.audit_skip = 1,
.async_size = sizeof(struct io_timeout_data),
.prep = io_timeout_prep,
.issue = io_timeout,
},
[IORING_OP_TIMEOUT_REMOVE] = {
/* used by timeout updates' prep() */
.audit_skip = 1,
.prep = io_timeout_remove_prep,
.issue = io_timeout_remove,
},
[IORING_OP_ACCEPT] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.poll_exclusive = 1,
.ioprio = 1, /* used for flags */
#if defined(CONFIG_NET)
.prep = io_accept_prep,
.issue = io_accept,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_ASYNC_CANCEL] = {
.audit_skip = 1,
.prep = io_async_cancel_prep,
.issue = io_async_cancel,
},
[IORING_OP_LINK_TIMEOUT] = {
.audit_skip = 1,
.async_size = sizeof(struct io_timeout_data),
.prep = io_link_timeout_prep,
.issue = io_no_issue,
},
[IORING_OP_CONNECT] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_connect_prep,
.issue = io_connect,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_FALLOCATE] = {
.needs_file = 1,
.prep = io_fallocate_prep,
.issue = io_fallocate,
},
[IORING_OP_OPENAT] = {
.prep = io_openat_prep,
.issue = io_openat,
},
[IORING_OP_CLOSE] = {
.prep = io_close_prep,
.issue = io_close,
},
[IORING_OP_FILES_UPDATE] = {
.audit_skip = 1,
.iopoll = 1,
.prep = io_files_update_prep,
.issue = io_files_update,
},
[IORING_OP_STATX] = {
.audit_skip = 1,
.prep = io_statx_prep,
.issue = io_statx,
},
[IORING_OP_READ] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.buffer_select = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_read,
.issue = io_read,
},
[IORING_OP_WRITE] = {
.needs_file = 1,
.hash_reg_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.plug = 1,
.audit_skip = 1,
.ioprio = 1,
.iopoll = 1,
.iopoll_queue = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_prep_write,
.issue = io_write,
},
[IORING_OP_FADVISE] = {
.needs_file = 1,
.audit_skip = 1,
.prep = io_fadvise_prep,
.issue = io_fadvise,
},
[IORING_OP_MADVISE] = {
.audit_skip = 1,
.prep = io_madvise_prep,
.issue = io_madvise,
},
[IORING_OP_SEND] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.audit_skip = 1,
.ioprio = 1,
.buffer_select = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_sendmsg_prep,
.issue = io_send,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_RECV] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.buffer_select = 1,
.audit_skip = 1,
.ioprio = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_recvmsg_prep,
.issue = io_recv,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_OPENAT2] = {
.prep = io_openat2_prep,
.issue = io_openat2,
},
[IORING_OP_EPOLL_CTL] = {
.unbound_nonreg_file = 1,
.audit_skip = 1,
#if defined(CONFIG_EPOLL)
.prep = io_epoll_ctl_prep,
.issue = io_epoll_ctl,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_SPLICE] = {
.needs_file = 1,
.hash_reg_file = 1,
.unbound_nonreg_file = 1,
.audit_skip = 1,
.prep = io_splice_prep,
.issue = io_splice,
},
[IORING_OP_PROVIDE_BUFFERS] = {
.audit_skip = 1,
.iopoll = 1,
.prep = io_provide_buffers_prep,
.issue = io_provide_buffers,
},
[IORING_OP_REMOVE_BUFFERS] = {
.audit_skip = 1,
.iopoll = 1,
.prep = io_remove_buffers_prep,
.issue = io_remove_buffers,
},
[IORING_OP_TEE] = {
.needs_file = 1,
.hash_reg_file = 1,
.unbound_nonreg_file = 1,
.audit_skip = 1,
.prep = io_tee_prep,
.issue = io_tee,
},
[IORING_OP_SHUTDOWN] = {
.needs_file = 1,
#if defined(CONFIG_NET)
.prep = io_shutdown_prep,
.issue = io_shutdown,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_RENAMEAT] = {
.prep = io_renameat_prep,
.issue = io_renameat,
},
[IORING_OP_UNLINKAT] = {
.prep = io_unlinkat_prep,
.issue = io_unlinkat,
},
[IORING_OP_MKDIRAT] = {
.prep = io_mkdirat_prep,
.issue = io_mkdirat,
},
[IORING_OP_SYMLINKAT] = {
.prep = io_symlinkat_prep,
.issue = io_symlinkat,
},
[IORING_OP_LINKAT] = {
.prep = io_linkat_prep,
.issue = io_linkat,
},
[IORING_OP_MSG_RING] = {
.needs_file = 1,
.iopoll = 1,
.prep = io_msg_ring_prep,
.issue = io_msg_ring,
},
[IORING_OP_FSETXATTR] = {
.needs_file = 1,
.prep = io_fsetxattr_prep,
.issue = io_fsetxattr,
},
[IORING_OP_SETXATTR] = {
.prep = io_setxattr_prep,
.issue = io_setxattr,
},
[IORING_OP_FGETXATTR] = {
.needs_file = 1,
.prep = io_fgetxattr_prep,
.issue = io_fgetxattr,
},
[IORING_OP_GETXATTR] = {
.prep = io_getxattr_prep,
.issue = io_getxattr,
},
[IORING_OP_SOCKET] = {
.audit_skip = 1,
#if defined(CONFIG_NET)
.prep = io_socket_prep,
.issue = io_socket,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_URING_CMD] = {
.needs_file = 1,
.plug = 1,
.iopoll = 1,
.iopoll_queue = 1,
.async_size = 2 * sizeof(struct io_uring_sqe),
.prep = io_uring_cmd_prep,
.issue = io_uring_cmd,
},
[IORING_OP_SEND_ZC] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.audit_skip = 1,
.ioprio = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_send_zc_prep,
.issue = io_send_zc,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_SENDMSG_ZC] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollout = 1,
.ioprio = 1,
#if defined(CONFIG_NET)
.async_size = sizeof(struct io_async_msghdr),
.prep = io_send_zc_prep,
.issue = io_sendmsg_zc,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_READ_MULTISHOT] = {
.needs_file = 1,
.unbound_nonreg_file = 1,
.pollin = 1,
.buffer_select = 1,
.audit_skip = 1,
.async_size = sizeof(struct io_async_rw),
.prep = io_read_mshot_prep,
.issue = io_read_mshot,
},
[IORING_OP_WAITID] = {
.async_size = sizeof(struct io_waitid_async),
.prep = io_waitid_prep,
.issue = io_waitid,
},
[IORING_OP_FUTEX_WAIT] = {
#if defined(CONFIG_FUTEX)
.prep = io_futex_prep,
.issue = io_futex_wait,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_FUTEX_WAKE] = {
#if defined(CONFIG_FUTEX)
.prep = io_futex_prep,
.issue = io_futex_wake,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_FUTEX_WAITV] = {
#if defined(CONFIG_FUTEX)
.prep = io_futexv_prep,
.issue = io_futexv_wait,
#else
.prep = io_eopnotsupp_prep,
#endif
},
[IORING_OP_FIXED_FD_INSTALL] = {
.needs_file = 1,
.prep = io_install_fixed_fd_prep,
.issue = io_install_fixed_fd,
},
[IORING_OP_FTRUNCATE] = {
.needs_file = 1,
.hash_reg_file = 1,
.prep = io_ftruncate_prep,
.issue = io_ftruncate,
},
};
const struct io_cold_def io_cold_defs[] = {
[IORING_OP_NOP] = {
.name = "NOP",
},
[IORING_OP_READV] = {
.name = "READV",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_WRITEV] = {
.name = "WRITEV",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_FSYNC] = {
.name = "FSYNC",
},
[IORING_OP_READ_FIXED] = {
.name = "READ_FIXED",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_WRITE_FIXED] = {
.name = "WRITE_FIXED",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_POLL_ADD] = {
.name = "POLL_ADD",
},
[IORING_OP_POLL_REMOVE] = {
.name = "POLL_REMOVE",
},
[IORING_OP_SYNC_FILE_RANGE] = {
.name = "SYNC_FILE_RANGE",
},
[IORING_OP_SENDMSG] = {
.name = "SENDMSG",
#if defined(CONFIG_NET)
.cleanup = io_sendmsg_recvmsg_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_RECVMSG] = {
.name = "RECVMSG",
#if defined(CONFIG_NET)
.cleanup = io_sendmsg_recvmsg_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_TIMEOUT] = {
.name = "TIMEOUT",
},
[IORING_OP_TIMEOUT_REMOVE] = {
.name = "TIMEOUT_REMOVE",
},
[IORING_OP_ACCEPT] = {
.name = "ACCEPT",
},
[IORING_OP_ASYNC_CANCEL] = {
.name = "ASYNC_CANCEL",
},
[IORING_OP_LINK_TIMEOUT] = {
.name = "LINK_TIMEOUT",
},
[IORING_OP_CONNECT] = {
.name = "CONNECT",
},
[IORING_OP_FALLOCATE] = {
.name = "FALLOCATE",
},
[IORING_OP_OPENAT] = {
.name = "OPENAT",
.cleanup = io_open_cleanup,
},
[IORING_OP_CLOSE] = {
.name = "CLOSE",
},
[IORING_OP_FILES_UPDATE] = {
.name = "FILES_UPDATE",
},
[IORING_OP_STATX] = {
.name = "STATX",
.cleanup = io_statx_cleanup,
},
[IORING_OP_READ] = {
.name = "READ",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_WRITE] = {
.name = "WRITE",
.cleanup = io_readv_writev_cleanup,
.fail = io_rw_fail,
},
[IORING_OP_FADVISE] = {
.name = "FADVISE",
},
[IORING_OP_MADVISE] = {
.name = "MADVISE",
},
[IORING_OP_SEND] = {
.name = "SEND",
#if defined(CONFIG_NET)
.cleanup = io_sendmsg_recvmsg_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_RECV] = {
.name = "RECV",
#if defined(CONFIG_NET)
.cleanup = io_sendmsg_recvmsg_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_OPENAT2] = {
.name = "OPENAT2",
.cleanup = io_open_cleanup,
},
[IORING_OP_EPOLL_CTL] = {
.name = "EPOLL",
},
[IORING_OP_SPLICE] = {
.name = "SPLICE",
},
[IORING_OP_PROVIDE_BUFFERS] = {
.name = "PROVIDE_BUFFERS",
},
[IORING_OP_REMOVE_BUFFERS] = {
.name = "REMOVE_BUFFERS",
},
[IORING_OP_TEE] = {
.name = "TEE",
},
[IORING_OP_SHUTDOWN] = {
.name = "SHUTDOWN",
},
[IORING_OP_RENAMEAT] = {
.name = "RENAMEAT",
.cleanup = io_renameat_cleanup,
},
[IORING_OP_UNLINKAT] = {
.name = "UNLINKAT",
.cleanup = io_unlinkat_cleanup,
},
[IORING_OP_MKDIRAT] = {
.name = "MKDIRAT",
.cleanup = io_mkdirat_cleanup,
},
[IORING_OP_SYMLINKAT] = {
.name = "SYMLINKAT",
.cleanup = io_link_cleanup,
},
[IORING_OP_LINKAT] = {
.name = "LINKAT",
.cleanup = io_link_cleanup,
},
[IORING_OP_MSG_RING] = {
.name = "MSG_RING",
.cleanup = io_msg_ring_cleanup,
},
[IORING_OP_FSETXATTR] = {
.name = "FSETXATTR",
.cleanup = io_xattr_cleanup,
},
[IORING_OP_SETXATTR] = {
.name = "SETXATTR",
.cleanup = io_xattr_cleanup,
},
[IORING_OP_FGETXATTR] = {
.name = "FGETXATTR",
.cleanup = io_xattr_cleanup,
},
[IORING_OP_GETXATTR] = {
.name = "GETXATTR",
.cleanup = io_xattr_cleanup,
},
[IORING_OP_SOCKET] = {
.name = "SOCKET",
},
[IORING_OP_URING_CMD] = {
.name = "URING_CMD",
},
[IORING_OP_SEND_ZC] = {
.name = "SEND_ZC",
#if defined(CONFIG_NET)
.cleanup = io_send_zc_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_SENDMSG_ZC] = {
.name = "SENDMSG_ZC",
#if defined(CONFIG_NET)
.cleanup = io_send_zc_cleanup,
.fail = io_sendrecv_fail,
#endif
},
[IORING_OP_READ_MULTISHOT] = {
.name = "READ_MULTISHOT",
.cleanup = io_readv_writev_cleanup,
},
[IORING_OP_WAITID] = {
.name = "WAITID",
},
[IORING_OP_FUTEX_WAIT] = {
.name = "FUTEX_WAIT",
},
[IORING_OP_FUTEX_WAKE] = {
.name = "FUTEX_WAKE",
},
[IORING_OP_FUTEX_WAITV] = {
.name = "FUTEX_WAITV",
},
[IORING_OP_FIXED_FD_INSTALL] = {
.name = "FIXED_FD_INSTALL",
},
[IORING_OP_FTRUNCATE] = {
.name = "FTRUNCATE",
},
};
const char *io_uring_get_opcode(u8 opcode)
{
if (opcode < IORING_OP_LAST)
return io_cold_defs[opcode].name;
return "INVALID";
}
void __init io_uring_optable_init(void)
{
int i;
BUILD_BUG_ON(ARRAY_SIZE(io_cold_defs) != IORING_OP_LAST);
BUILD_BUG_ON(ARRAY_SIZE(io_issue_defs) != IORING_OP_LAST);
for (i = 0; i < ARRAY_SIZE(io_issue_defs); i++) {
BUG_ON(!io_issue_defs[i].prep);
if (io_issue_defs[i].prep != io_eopnotsupp_prep)
BUG_ON(!io_issue_defs[i].issue);
WARN_ON_ONCE(!io_cold_defs[i].name);
}
}