In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix double free of wq, engine, and group structs The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redundant ex...

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix double free of wq, engine, and group structs The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redundant ex...

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix double free of wq, engine, and group structs The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redundant

dmaengine: idxd: fix double free of wq, engine, and group structs

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

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix double free of wq, engine, and group structs The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redunda...