Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted

Pull io_uring fixes from Jens Axboe:

 - Fix a task_work add use-after-free with SQPOLL.

   The sqpoll thread could pop and complete the last request while
   io_req_normal_work_add() was still looking at them after the mpscq
   push.

   Use the same approach as DEFER_TASKRUN to protect from that, holding
   an RCU read lock across the add, and have exit wait for an RCU grace
   period for SQPOLL rings as well.

 - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
   big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
   rings

 - Mark the source filter table as COW when cloning bpf filters, so
   registering another filter on the source doesn't modify the shared
   table in place

 - Initialize the task context before running the BPF loop

 - Requeue zcrx multishot receives stopped by a local resource

 - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)

* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  io_uring: fix task_work add use-after-free with SQPOLL
  io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
  io_uring/zcrx: requeue multishot receives stopped by a local resource
  io_uring: initialize task context before running the BPF loop
  io_uring: zero big_cqe for aux CQEs on CQE32 rings
  io_uring: fix free entry check for 32b CQEs on CQE32 rings
  io_uring: only post the dummy skip CQE on CQE_MIXED rings
  io_uring/bpf_filter: mark source as COW when cloning filters

1 files changed, 272 insertions, 0 deletions

diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
new file mode 100644
index 000000000..3ae480476
--- /dev/null
+++ b/io_uring/fdinfo.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/nospec.h>
+#include <linux/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "filetable.h"
+#include "sqpoll.h"
+#include "fdinfo.h"
+#include "cancel.h"
+#include "rsrc.h"
+#include "opdef.h"
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+static __cold void common_tracking_show_fdinfo(struct io_ring_ctx *ctx,
+					       struct seq_file *m,
+					       const char *tracking_strategy)
+{
+	seq_puts(m, "NAPI:\tenabled\n");
+	seq_printf(m, "napi tracking:\t%s\n", tracking_strategy);
+	seq_printf(m, "napi_busy_poll_dt:\t%llu\n", ctx->napi_busy_poll_dt);
+	if (ctx->napi_prefer_busy_poll)
+		seq_puts(m, "napi_prefer_busy_poll:\ttrue\n");
+	else
+		seq_puts(m, "napi_prefer_busy_poll:\tfalse\n");
+}
+
+static __cold void napi_show_fdinfo(struct io_ring_ctx *ctx,
+				    struct seq_file *m)
+{
+	unsigned int mode = READ_ONCE(ctx->napi_track_mode);
+
+	switch (mode) {
+	case IO_URING_NAPI_TRACKING_INACTIVE:
+		seq_puts(m, "NAPI:\tdisabled\n");
+		break;
+	case IO_URING_NAPI_TRACKING_DYNAMIC:
+		common_tracking_show_fdinfo(ctx, m, "dynamic");
+		break;
+	case IO_URING_NAPI_TRACKING_STATIC:
+		common_tracking_show_fdinfo(ctx, m, "static");
+		break;
+	default:
+		seq_printf(m, "NAPI:\tunknown mode (%u)\n", mode);
+	}
+}
+#else
+static inline void napi_show_fdinfo(struct io_ring_ctx *ctx,
+				    struct seq_file *m)
+{
+}
+#endif
+
+static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
+{
+	struct io_overflow_cqe *ocqe;
+	struct io_rings *r = ctx->rings;
+	unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
+	unsigned int sq_head = READ_ONCE(r->sq.head);
+	unsigned int sq_tail = READ_ONCE(r->sq.tail);
+	unsigned int cq_head = READ_ONCE(r->cq.head);
+	unsigned int cq_tail = READ_ONCE(r->cq.tail);
+	unsigned int sq_shift = 0;
+	unsigned int cq_entries, sq_entries;
+	int sq_pid = -1, sq_cpu = -1;
+	u64 sq_total_time = 0, sq_work_time = 0;
+	unsigned int i;
+
+	if (ctx->flags & IORING_SETUP_SQE128)
+		sq_shift = 1;
+
+	/*
+	 * we may get imprecise sqe and cqe info if uring is actively running
+	 * since we get cached_sq_head and cached_cq_tail without uring_lock
+	 * and sq_tail and cq_head are changed by userspace. But it's ok since
+	 * we usually use these info when it is stuck.
+	 */
+	seq_printf(m, "SqMask:\t0x%x\n", sq_mask);
+	seq_printf(m, "SqHead:\t%u\n", sq_head);
+	seq_printf(m, "SqTail:\t%u\n", sq_tail);
+	seq_printf(m, "CachedSqHead:\t%u\n", data_race(ctx->cached_sq_head));
+	seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
+	seq_printf(m, "CqHead:\t%u\n", cq_head);
+	seq_printf(m, "CqTail:\t%u\n", cq_tail);
+	seq_printf(m, "CachedCqTail:\t%u\n", data_race(ctx->cached_cq_tail));
+	seq_printf(m, "SQEs:\t%u\n", sq_tail - sq_head);
+	sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
+	for (i = 0; i < sq_entries; i++) {
+		unsigned int entry = i + sq_head;
+		struct io_uring_sqe *sqe;
+		unsigned int sq_idx;
+		bool sqe128 = false;
+		u8 opcode;
+
+		if (ctx->flags & IORING_SETUP_NO_SQARRAY)
+			sq_idx = entry & sq_mask;
+		else
+			sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
+		if (sq_idx > sq_mask)
+			continue;
+
+		sqe = &ctx->sq_sqes[sq_idx << sq_shift];
+		opcode = READ_ONCE(sqe->opcode);
+		if (opcode >= IORING_OP_LAST)
+			continue;
+		opcode = array_index_nospec(opcode, IORING_OP_LAST);
+		if (sq_shift) {
+			sqe128 = true;
+		} else if (io_issue_defs[opcode].is_128) {
+			if (!(ctx->flags & IORING_SETUP_SQE_MIXED)) {
+				seq_printf(m,
+					"%5u: invalid sqe, 128B entry on non-mixed sq\n",
+					sq_idx);
+				break;
+			}
+			if (sq_idx == sq_mask) {
+				seq_printf(m,
+					"%5u: corrupted sqe, wrapping 128B entry\n",
+					sq_idx);
+				break;
+			}
+			sq_head++;
+			i++;
+			sqe128 = true;
+		}
+		seq_printf(m, "%5u: opcode:%s, fd:%d, flags:%x, off:%llu, "
+			      "addr:0x%llx, rw_flags:0x%x, buf_index:%d "
+			      "user_data:%llu",
+			   sq_idx, io_uring_get_opcode(opcode), sqe->fd,
+			   sqe->flags, (unsigned long long) sqe->off,
+			   (unsigned long long) sqe->addr, sqe->rw_flags,
+			   sqe->buf_index, sqe->user_data);
+		if (sqe128) {
+			u64 *sqeb = (void *) (sqe + 1);
+			int size = sizeof(struct io_uring_sqe) / sizeof(u64);
+			int j;
+
+			for (j = 0; j < size; j++) {
+				seq_printf(m, ", e%d:0x%llx", j,
+						(unsigned long long) *sqeb);
+				sqeb++;
+			}
+		}
+		seq_printf(m, "\n");
+		cond_resched();
+	}
+	seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
+	cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
+	for (i = 0; i < cq_entries; i++) {
+		struct io_uring_cqe *cqe;
+		bool cqe32 = false;
+
+		cqe = &r->cqes[(cq_head & cq_mask)];
+		if (cqe->flags & IORING_CQE_F_32 || ctx->flags & IORING_SETUP_CQE32)
+			cqe32 = true;
+		seq_printf(m, "%5u: user_data:%llu, res:%d, flags:%x",
+			   cq_head & cq_mask, cqe->user_data, cqe->res,
+			   cqe->flags);
+		if (cqe32)
+			seq_printf(m, ", extra1:%llu, extra2:%llu",
+					cqe->big_cqe[0], cqe->big_cqe[1]);
+		seq_printf(m, "\n");
+		cq_head++;
+		if (cqe32) {
+			cq_head++;
+			i++;
+		}
+		cond_resched();
+	}
+
+	if (ctx->flags & IORING_SETUP_SQPOLL) {
+		struct io_sq_data *sq = ctx->sq_data;
+		struct task_struct *tsk;
+
+		rcu_read_lock();
+		tsk = rcu_dereference(sq->thread);
+		/*
+		 * sq->thread might be NULL if we raced with the sqpoll
+		 * thread termination.
+		 */
+		if (tsk) {
+			u64 usec;
+
+			get_task_struct(tsk);
+			rcu_read_unlock();
+			usec = io_sq_cpu_usec(tsk);
+			sq_pid = task_pid_nr_ns(tsk,
+						proc_pid_ns(file_inode(m->file)->i_sb));
+			put_task_struct(tsk);
+			sq_cpu = sq->sq_cpu;
+			sq_total_time = usec;
+			sq_work_time = sq->work_time;
+		} else {
+			rcu_read_unlock();
+		}
+	}
+
+	seq_printf(m, "SqThread:\t%d\n", sq_pid);
+	seq_printf(m, "SqThreadCpu:\t%d\n", sq_cpu);
+	seq_printf(m, "SqTotalTime:\t%llu\n", sq_total_time);
+	seq_printf(m, "SqWorkTime:\t%llu\n", sq_work_time);
+	seq_printf(m, "UserFiles:\t%u\n", ctx->file_table.data.nr);
+	for (i = 0; i < ctx->file_table.data.nr; i++) {
+		struct file *f = NULL;
+
+		if (ctx->file_table.data.nodes[i])
+			f = io_slot_file(ctx->file_table.data.nodes[i]);
+		if (f) {
+			seq_printf(m, "%5u: ", i);
+			seq_file_path(m, f, " \t\n\\");
+			seq_puts(m, "\n");
+		}
+	}
+	seq_printf(m, "UserBufs:\t%u\n", ctx->buf_table.nr);
+	for (i = 0; i < ctx->buf_table.nr; i++) {
+		struct io_mapped_ubuf *buf = NULL;
+
+		if (ctx->buf_table.nodes[i])
+			buf = ctx->buf_table.nodes[i]->buf;
+		if (buf)
+			seq_printf(m, "%5u: 0x%llx/%zu\n", i, buf->ubuf, buf->len);
+		else
+			seq_printf(m, "%5u: <none>\n", i);
+	}
+
+	seq_puts(m, "PollList:\n");
+	for (i = 0; i < (1U << ctx->cancel_table.hash_bits); i++) {
+		struct io_hash_bucket *hb = &ctx->cancel_table.hbs[i];
+		struct io_kiocb *req;
+
+		hlist_for_each_entry(req, &hb->list, hash_node)
+			seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
+					task_work_pending(req->tctx->task));
+	}
+
+	seq_puts(m, "CqOverflowList:\n");
+	spin_lock(&ctx->completion_lock);
+	list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
+		struct io_uring_cqe *cqe = &ocqe->cqe;
+
+		seq_printf(m, "  user_data=%llu, res=%d, flags=%x\n",
+			   cqe->user_data, cqe->res, cqe->flags);
+
+	}
+	spin_unlock(&ctx->completion_lock);
+	napi_show_fdinfo(ctx, m);
+}
+
+/*
+ * Caller holds a reference to the file already, we don't need to do
+ * anything else to get an extra reference.
+ */
+__cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file)
+{
+	struct io_ring_ctx *ctx = file->private_data;
+
+	/*
+	 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
+	 * since fdinfo case grabs it in the opposite direction of normal use
+	 * cases.
+	 */
+	if (mutex_trylock(&ctx->uring_lock)) {
+		__io_uring_show_fdinfo(ctx, m);
+		mutex_unlock(&ctx->uring_lock);
+	}
+}