Linux Kernel bnxt_re RDMA Driver: Unzeroed Shared Page Leak
CVE-2026-74584 Published on August 22, 2026
RDMA/bnxt_re: zero shared page before exposing to userspace
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: zero shared page before exposing to userspace
bnxt_re_alloc_ucontext() allocates uctx->shpg via
__get_free_page(GFP_KERNEL). The buddy allocator does not zero pages
without __GFP_ZERO, so the page contains stale kernel data from
whatever object most recently freed it.
The page is then mapped into userspace via vm_insert_page() under
BNXT_RE_MMAP_SH_PAGE in bnxt_re_mmap(). The driver only ever writes
4 bytes (a u32 AVID) at offset BNXT_RE_AVID_OFFT (0x10) inside
bnxt_re_create_ah(); the remaining 4092 bytes of the page are exposed
to userspace unsanitised, leaking kernel memory contents.
Any user with access to /dev/infiniband/uverbsX on a host with a
bnxt_re device (typically rdma group membership) can read this data
via a single mmap() at pgoff 0 after IB_USER_VERBS_CMD_GET_CONTEXT.
Other shared pages in the same file already use get_zeroed_page()
correctly:
drivers/infiniband/hw/bnxt_re/ib_verbs.c
srq->uctx_srq_page = (void *)get_zeroed_page(GFP_KERNEL);
cq->uctx_cq_page = (void *)get_zeroed_page(GFP_KERNEL);
uctx->shpg is the only outlier. Bring it in line with the existing
convention by switching to get_zeroed_page().
Products Associated with CVE-2026-74584
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Affected Versions
Linux:- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below 53c97e9882f4e747b4ac31b211317c2eba541af9 is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below 9896bdfd21d918e9f26a52bc6109cc77970ee0b1 is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below 9128c2411b83a64c0a69d2ff059c741bde25a9cc is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below c19b360fa10c521c0b681875cdaa51545d45a491 is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below a3ed2daab02b2a706e882ad31b5c3c4f33cb5bb1 is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below e2b143df29003d2704b51f62e9297006953dbacb is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below c75f8ce4baa29ae57fe615c6a2c5101f59b8b89a is affected.
- Version 1ac5a404797523cedaf424a3aaa3cf8f9548dff8 and below f6b079629becfa977f9c51fe53ad2e6dcc55ef44 is affected.
- Version 4.11 is affected.
- Before 4.11 is unaffected.
- Version 5.10.260, <= 5.10.* is unaffected.
- Version 5.15.211, <= 5.15.* is unaffected.
- Version 6.1.177, <= 6.1.* is unaffected.
- Version 6.6.144, <= 6.6.* is unaffected.
- Version 6.12.95, <= 6.12.* is unaffected.
- Version 6.18.37, <= 6.18.* is unaffected.
- Version 7.0.14, <= 7.0.* is unaffected.
- Version 7.1, <= * is unaffected.