kernel/linux.git/io_uring, branch v7.0-rc7

Merge tag 'io_uring-7.0-20260403' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

2026-04-03T18:58:04+00:00

Pull io_uring fixes from Jens Axboe: - A previous fix in this release covered the case of the rings being RCU protected during resize, but it missed a few spots. This covers the rest - Fix the cBPF filters when COW'ed, introduced in this merge window - Fix for an attempt to import a zero sized buffer - Fix for a missing clamp in importing bundle buffers * tag 'io_uring-7.0-20260403' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/bpf_filters: retain COW'ed settings on parse failures io_uring: protect remaining lockless ctx->rings accesses with RCU io_uring/rsrc: reject zero-length fixed buffer import io_uring/net: fix slab-out-of-bounds read in io_bundle_nbufs()

io_uring/bpf_filters: retain COW'ed settings on parse failures

2026-04-01T14:34:14+00:00

If io_parse_restrictions() fails, it ends up clearing any restrictions currently set. The intent is only to clear whatever it already applied, but it ends up clearing everything, including whatever settings may have been applied in a copy-on-write fashion already. Ensure that those are retained. Link: https://lore.kernel.org/io-uring/CAK8a0jzF-zaO5ZmdOrmfuxrhXuKg5m5+RDuO7tNvtj=kUYbW7Q@mail.gmail.com/ Reported-by: antonius Fixes: ed82f35b926b ("io_uring: allow registration of per-task restrictions") Signed-off-by: Jens Axboe

io_uring: protect remaining lockless ctx->rings accesses with RCU

2026-04-01T14:34:11+00:00

Commit 96189080265e addressed one case of ctx->rings being potentially accessed while a resize is happening on the ring, but there are still a few others that need handling. Add a helper for retrieving the rings associated with an io_uring context, and add some sanity checking to that to catch bad uses. ->rings_rcu is always valid, as long as it's used within RCU read lock. Any use of ->rings_rcu or ->rings inside either ->uring_lock or ->completion_lock is sane as well. Do the minimum fix for the current kernel, but set it up such that this basic infra can be extended for later kernels to make this harder to mess up in the future. Thanks to Junxi Qian for finding and debugging this issue. Cc: stable@vger.kernel.org Fixes: 79cfe9e59c2a ("io_uring/register: add IORING_REGISTER_RESIZE_RINGS") Reviewed-by: Junxi Qian Tested-by: Junxi Qian Link: https://lore.kernel.org/io-uring/20260330172348.89416-1-qjx1298677004@gmail.com/ Signed-off-by: Jens Axboe

io_uring/rsrc: reject zero-length fixed buffer import

2026-03-29T20:03:55+00:00

validate_fixed_range() admits buf_addr at the exact end of the registered region when len is zero, because the check uses strict greater-than (buf_end > imu->ubuf + imu->len). io_import_fixed() then computes offset == imu->len, which causes the bvec skip logic to advance past the last bio_vec entry and read bv_offset from out-of-bounds slab memory. Return early from io_import_fixed() when len is zero. A zero-length import has no data to transfer and should not walk the bvec array at all. BUG: KASAN: slab-out-of-bounds in io_import_reg_buf+0x697/0x7f0 Read of size 4 at addr ffff888002bcc254 by task poc/103 Call Trace: io_import_reg_buf+0x697/0x7f0 io_write_fixed+0xd9/0x250 __io_issue_sqe+0xad/0x710 io_issue_sqe+0x7d/0x1100 io_submit_sqes+0x86a/0x23c0 __do_sys_io_uring_enter+0xa98/0x1590 Allocated by task 103: The buggy address is located 12 bytes to the right of allocated 584-byte region [ffff888002bcc000, ffff888002bcc248) Fixes: 8622b20f23ed ("io_uring: add validate_fixed_range() for validate fixed buffer") Signed-off-by: Qi Tang Link: https://patch.msgid.link/20260329164936.240871-1-tpluszz77@gmail.com Signed-off-by: Jens Axboe

io_uring/net: fix slab-out-of-bounds read in io_bundle_nbufs()

2026-03-29T20:03:14+00:00

sqe->len is __u32 but gets stored into sr->len which is int. When userspace passes sqe->len values exceeding INT_MAX (e.g. 0xFFFFFFFF), sr->len overflows to a negative value. This negative value propagates through the bundle recv/send path: 1. io_recv(): sel.val = sr->len (ssize_t gets -1) 2. io_recv_buf_select(): arg.max_len = sel->val (size_t gets 0xFFFFFFFFFFFFFFFF) 3. io_ring_buffers_peek(): buf->len is not clamped because max_len is astronomically large 4. iov[].iov_len = 0xFFFFFFFF flows into io_bundle_nbufs() 5. io_bundle_nbufs(): min_t(int, 0xFFFFFFFF, ret) yields -1, causing ret to increase instead of decrease, creating an infinite loop that reads past the allocated iov[] array This results in a slab-out-of-bounds read in io_bundle_nbufs() from the kmalloc-64 slab, as nbufs increments past the allocated iovec entries. BUG: KASAN: slab-out-of-bounds in io_bundle_nbufs+0x128/0x160 Read of size 8 at addr ffff888100ae05c8 by task exp/145 Call Trace: io_bundle_nbufs+0x128/0x160 io_recv_finish+0x117/0xe20 io_recv+0x2db/0x1160 Fix this by rejecting negative sr->len values early in both io_sendmsg_prep() and io_recvmsg_prep(). Since sqe->len is __u32, any value > INT_MAX indicates overflow and is not a valid length. Fixes: a05d1f625c7a ("io_uring/net: support bundles for send") Cc: stable@vger.kernel.org Signed-off-by: Junxi Qian Link: https://patch.msgid.link/20260329153909.279046-1-qjx1298677004@gmail.com Signed-off-by: Jens Axboe

Merge tag 'io_uring-7.0-20260327' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

2026-03-27T22:35:38+00:00

Pull io_uring fixes from Jens Axboe: "Just two small fixes, both fixing regressions added in the fdinfo code in 6.19 with the SQE mixed size support" * tag 'io_uring-7.0-20260327' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check io_uring/fdinfo: fix SQE_MIXED SQE displaying

io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check

2026-03-27T02:28:28+00:00

__io_uring_show_fdinfo() iterates over pending SQEs and, for 128-byte SQEs on an IORING_SETUP_SQE_MIXED ring, needs to detect when the second half of the SQE would be past the end of the sq_sqes array. The current check tests (++sq_head & sq_mask) == 0, but sq_head is only incremented when a 128-byte SQE is encountered, not on every iteration. The actual array index is sq_idx = (i + sq_head) & sq_mask, which can be sq_mask (the last slot) while the wrap check passes. Fix by checking sq_idx directly. Keep the sq_head increment so the loop still skips the second half of the 128-byte SQE on the next iteration. Fixes: 1cba30bf9fdd ("io_uring: add support for IORING_SETUP_SQE_MIXED") Signed-off-by: Nicholas Carlini Link: https://patch.msgid.link/20260327021823.3138396-1-nicholas@carlini.com Signed-off-by: Jens Axboe

io_uring/fdinfo: fix SQE_MIXED SQE displaying

2026-03-26T13:15:55+00:00

When displaying pending SQEs for a MIXED ring, each 128-byte SQE increments sq_head to skip the second slot, but the loop counter is not adjusted. This can cause the loop to read past sq_tail by one entry for each 128-byte SQE encountered, displaying SQEs that haven't been made consumable yet by the application. Match the kernel's own consumption logic in io_init_req() which decrements what's left when consuming the extra slot. Fixes: 1cba30bf9fdd ("io_uring: add support for IORING_SETUP_SQE_MIXED") Signed-off-by: Jens Axboe

Merge tag 'io_uring-7.0-20260320' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux

2026-03-20T16:58:56+00:00

Pull io_uring fixes from Jens Axboe: - A bit of a work-around for AF_UNIX recv multishot, as the in-kernel implementation doesn't properly signal EOF. We'll likely rework this one going forward, but the fix is sufficient for now - Two fixes for incrementally consumed buffers, for non-pollable files and for 0 byte reads * tag 'io_uring-7.0-20260320' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/kbuf: propagate BUF_MORE through early buffer commit path io_uring/kbuf: fix missing BUF_MORE for incremental buffers at EOF io_uring/poll: fix multishot recv missing EOF on wakeup race

io_uring/kbuf: propagate BUF_MORE through early buffer commit path

2026-03-19T21:09:48+00:00

When io_should_commit() returns true (eg for non-pollable files), buffer commit happens at buffer selection time and sel->buf_list is set to NULL. When __io_put_kbufs() generates CQE flags at completion time, it calls __io_put_kbuf_ring() which finds a NULL buffer_list and hence cannot determine whether the buffer was consumed or not. This means that IORING_CQE_F_BUF_MORE is never set for non-pollable input with incrementally consumed buffers. Likewise for io_buffers_select(), which always commits upfront and discards the return value of io_kbuf_commit(). Add REQ_F_BUF_MORE to store the result of io_kbuf_commit() during early commit. Then __io_put_kbuf_ring() can check this flag and set IORING_F_BUF_MORE accordingy. Reported-by: Martin Michaelis Cc: stable@vger.kernel.org Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption") Link: https://github.com/axboe/liburing/issues/1553 Signed-off-by: Jens Axboe