In the Linux kernel, the following vulnerability has been resolved:
nfp: Check resource mutex allocation
nfp_cpp_resource_find() allocates a CPP mutex handle for the matching resource-table entry and then reports success. nfp_resource_try_acquire() immediately passes that handle to nfp_cpp_mutex_trylock().
However, nfp_cpp_mutex_alloc() returns NULL on failure. If that happens for a matching table entry, the resource lookup still returns success and the following trylock dereferences a NULL mutex pointer while opening the resource.
nfp_resource_acquire() already treats failure to allocate the table mutex as -ENOMEM. Do the same for the resource mutex and fail the lookup before publishing the rest of the resource handle.
This issue was found by a static analysis checker and confirmed by manual source review.
References
- https://git.kernel.org/stable/c/3b1d4fc3b73ea6faf008a0996ce6190c6e43efc3
- https://git.kernel.org/stable/c/6dbd428119cb1fd1b73cf6968c711f4ea964dc8b
- https://git.kernel.org/stable/c/a61b4db34a753bdf5c9e77a7f3d3dddd41dcfacc
- https://git.kernel.org/stable/c/a7dc30b6828c3a30252892827b12b676749f250f
- https://git.kernel.org/stable/c/cfa119aa781c4044dab5b4c1e5864600f53a26bc