CVE-2026-45856
published 2026-05-27CVE-2026-45856: In the Linux kernel, the following vulnerability has been resolved: RDMA/uverbs: Validate wqe_size before using it in ib_uverbs_post_send ib_uverbs_post_send()…
high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
In the Linux kernel, the following vulnerability has been resolved:
RDMA/uverbs: Validate wqe_size before using it in ib_uverbs_post_send
ib_uverbs_post_send() uses cmd.wqe_size from userspace without any
validation before passing it to kmalloc() and using the allocated
buffer as struct ib_uverbs_send_wr.
If a user provides a small wqe_size value (e.g., 1), kmalloc() will
succeed, but subsequent accesses to user_wr->opcode, user_wr->num_sge,
and other fields will read beyond the allocated buffer, resulting in
an out-of-bounds read from kernel heap memory. This could potentially
leak sensitive kernel information to userspace.
Additionally, providing an excessively large wqe_size can trigger a
WARNING in the memory allocation path, as reported by syzkaller.
This is inconsistent with ib_uverbs_unmarshall_recv() which properly
validates that wqe_size >= sizeof(struct ib_uverbs_recv_wr) before
proceeding.
Add the same validation for ib_uverbs_post_send() to ensure wqe_size
is at least sizeof(struct ib_uverbs_send_wr).
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < 9c15ec4cd4e7f57c6bbcb4e73e99290f150dd2a7 | 9c15ec4cd4e7f57c6bbcb4e73e99290f150dd2a7 |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < 9b5ac1c15334d46c0dbd49d64a2257b929500163 | 9b5ac1c15334d46c0dbd49d64a2257b929500163 |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < 01c9b152647dc70dc06a4a2eff86ebb3b3c76075 | 01c9b152647dc70dc06a4a2eff86ebb3b3c76075 |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < bf1feed1a7886af945f92890493aefd2b5c9928a | bf1feed1a7886af945f92890493aefd2b5c9928a |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < d533425ac1f2925b4fc3e4ed9b9d72362cb23475 | d533425ac1f2925b4fc3e4ed9b9d72362cb23475 |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < bf4454da8b1e712714628c0a0d6e7845bb40790a | bf4454da8b1e712714628c0a0d6e7845bb40790a |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < bef70ff9841990658610512b4a18e4a88c9b4df6 | bef70ff9841990658610512b4a18e4a88c9b4df6 |
| linux | linux | >= c3bea3d2dc5358e05541527283279102383b0231 < 1956f0a74ccf5dc9c3ef717f2985c3ed3400aab0 | 1956f0a74ccf5dc9c3ef717f2985c3ed3400aab0 |
| linux | linux_kernel | — | — |