CVE-2026-89511

In the Linux kernel, the following vulnerability has been resolved:

qede: Fix NULL pointer dereference in TPA fragment processing

Under memory pressure, the qede driver encounters NULL pointer dereferences when processing TPA continuation fragments.

Commit 8a8633978b84 ("qede: Add build skb() support.") accidentally dropped the assignment of tpa info->buffer.data in qede tpa start().

When memory pressure causes an SKB allocation failure in qede tpa start(), the driver sets tpa start fail = true and attempts to recycle the physical page later in qede tpa end() via qede reuse page(). However, because buffer.data was left uninitialized (NULL), qede reuse page() pushes a "ghost" BD (valid DMA mapping but NULL data pointer) back into the active Rx ring.

The next time the hardware uses this ring slot, it passes a NULL page to qede fill frag skb(), causing a kernel panic.

Example crash from production system: BUG: unable to handle kernel NULL pointer dereference at 0x8 RIP: qede fill frag skb+0x96/0x430 [qede] Call Trace: qede rx int+0xb06/0x1de0 qede poll+0x2f4/0x6c0 napi poll+0x2d/0x130

Fix the root cause by restoring the tpa info->buffer.data assignment in qede tpa start(), ensuring valid pages are correctly tracked and recycled. Additionally, update the stale comment for struct qede agg info::buffer to reflect its current usage.