ubi: fastmap: Fix duplicate slab cache names while attaching

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: ubi: fastmap: Fix duplicate slab cache names while attaching Since commit 4c39529663b9 ("slab: Warn on duplicate cache names when DEBUG_VM=y"), the duplicate slab cache names can be detected and a kernel WARNING is thrown out. In UBI fast attaching process, alloc_ai() could be invoked twice with the same slab cache name 'ubi_aeb_slab_cache', which will trigger following warning messages: kmem_cache of name 'ubi_aeb_slab_cache' already exists WARNING: CPU: 0 PID: 7519 at mm/slab_common.c:107 __kmem_cache_create_args+0x100/0x5f0 Modules linked in: ubi(+) nandsim [last unloaded: nandsim] CPU: 0 UID: 0 PID: 7519 Comm: modprobe Tainted: G 6.12.0-rc2 RIP: 0010:__kmem_cache_create_args+0x100/0x5f0 Call Trace: __kmem_cache_create_args+0x100/0x5f0 alloc_ai+0x295/0x3f0 [ubi] ubi_attach+0x3c3/0xcc0 [ubi] ubi_attach_mtd_dev+0x17cf/0x3fa0 [ubi] ubi_init+0x3fb/0x800 [ubi] do_init_module+0x265/0x7d0 __x64_sys_finit_module+0x7a/0xc0 The problem could be easily reproduced by loading UBI device by fastmap with CONFIG_DEBUG_VM=y. Fix it by using different slab names for alloc_ai() callers.

References

• https://git.kernel.org/stable/c/ef52b7191ac41e68b1bf070d00c5b04ed16e4920
• https://git.kernel.org/stable/c/871c148f8e0c32e505df9393ba4a303c3c3fe988
• https://git.kernel.org/stable/c/04c0b0f37617099479c34e207c5550d081f585a6
• https://git.kernel.org/stable/c/b1ee0aa4945c49cbbd779da81040fcec4de80fd1
• https://git.kernel.org/stable/c/6afdcb285794e75d2c8995e3a44f523c176cc2de
• https://git.kernel.org/stable/c/612824dd0c9465ef365ace38b056c663d110956d
• https://git.kernel.org/stable/c/3d8558135cd56a2a8052024be4073e160f36658c
• https://git.kernel.org/stable/c/7402c4bcb8a3f0d2ef4e687cd45c76be489cf509
• https://git.kernel.org/stable/c/bcddf52b7a17adcebc768d26f4e27cf79adb424c