In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev
If the mmio_pipe_open() fails to find a PCI device, the hiter->dev will be assigned to NULL. The mmiotrace read() function dereferences the hiter->dev if hiter exists.
Change the test of the read to not only check hiter being NULL, but also the hiter->dev before dereferencing it.
References
- https://git.kernel.org/stable/c/144f29e85702234b23d2a62abf723e6a17eb5427
- https://git.kernel.org/stable/c/201a01102c529772168181190cb084471082cf5c
- https://git.kernel.org/stable/c/724cd84b0546c07806840fa658714488553d13a2
- https://git.kernel.org/stable/c/8464427e1c177809a9488a97dfa2807d9dcf323b
- https://git.kernel.org/stable/c/faaf95135184208ee3ac6f33175c8d1800669dfc