CVE-2026-46029

The record

In the Linux kernel, the following vulnerability has been resolved: mm/slab: return NULL early from kmalloc_nolock() in NMI on UP On UP kernels (!CONFIG_SMP), spin_trylock() is a no-op that unconditionally succeeds even when the lock is already held. As a result, kmalloc_nolock() called from NMI context can re-enter the slab allocator and acquire n->list_lock that the interrupted context is already holding, corrupting slab state. With CONFIG_DEBUG_SPINLOCK on UP, the following BUG is triggered with the slub_kunit test module: BUG: spinlock trylock failure on UP on CPU#0, kunit_try_catch/243 [...] Call Trace: <NMI> dump_stack_lvl+0x3f/0x60 do_raw_spin_trylock+0x41/0x50 _raw_spin_trylock+0x24/0x50 get_from_partial_node+0x120/0x4d0 ___slab_alloc+0x8a/0x4c0 kmalloc_nolock_noprof+0x164/0x310 [...] </NMI> Fix this by returning NULL early when invoked from NMI on a UP kernel.

Affected packages

Related vulnerabilities

• CVE-2026-53354 In the Linux kernel, the following vulnerability has been resolved: arm64: errata… Also affects kernel-source
• CVE-2026-53325 In the Linux kernel, the following vulnerability has been resolved: agp/amd64: Fix broken… Also affects kernel-source
• CVE-2026-52946 In the Linux kernel, the following vulnerability has been resolved: fs/fcntl: fix… Also affects kernel-source
• CVE-2026-52907 In the Linux kernel, the following vulnerability has been resolved: media: rockchip… Also affects kernel-source
• CVE-2026-52906 In the Linux kernel, the following vulnerability has been resolved: 9p: fix access mode… Also affects kernel-source
• CVE-2026-52905 In the Linux kernel, the following vulnerability has been resolved: mm/damon/core… Also affects kernel-source
• CVE-2026-52904 In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix… Also affects kernel-source
• CVE-2026-46332 In the Linux kernel, the following vulnerability has been resolved: greybus… Also affects kernel-source