3.7 KiB
CVE-2024-53097
Description
In the Linux kernel, the following vulnerability has been resolved:mm: krealloc: Fix MTE false alarm in __do_kreallocThis patch addresses an issue introduced by commit 1a83a716ec233 ("mm:krealloc: consider spare memory for __GFP_ZERO") which causes MTE(Memory Tagging Extension) to falsely report a slab-out-of-bounds error.The problem occurs when zeroing out spare memory in __do_krealloc. Theoriginal code only considered software-based KASAN and did not accountfor MTE. It does not reset the KASAN tag before calling memset, leadingto a mismatch between the pointer tag and the memory tag, resultingin a false positive.Example of the error:==================================================================swapper/0: BUG: KASAN: slab-out-of-bounds in __memset+0x84/0x188swapper/0: Write at addr f4ffff8005f0fdf0 by task swapper/0/1swapper/0: Pointer tag: [f4], memory tag: [fe]swapper/0:swapper/0: CPU: 4 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.swapper/0: Hardware name: MT6991(ENG) (DT)swapper/0: Call trace:swapper/0: dump_backtrace+0xfc/0x17cswapper/0: show_stack+0x18/0x28swapper/0: dump_stack_lvl+0x40/0xa0swapper/0: print_report+0x1b8/0x71cswapper/0: kasan_report+0xec/0x14cswapper/0: __do_kernel_fault+0x60/0x29cswapper/0: do_bad_area+0x30/0xdcswapper/0: do_tag_check_fault+0x20/0x34swapper/0: do_mem_abort+0x58/0x104swapper/0: el1_abort+0x3c/0x5cswapper/0: el1h_64_sync_handler+0x80/0xccswapper/0: el1h_64_sync+0x68/0x6cswapper/0: __memset+0x84/0x188swapper/0: btf_populate_kfunc_set+0x280/0x3d8swapper/0: __register_btf_kfunc_id_set+0x43c/0x468swapper/0: register_btf_kfunc_id_set+0x48/0x60swapper/0: register_nf_nat_bpf+0x1c/0x40swapper/0: nf_nat_init+0xc0/0x128swapper/0: do_one_initcall+0x184/0x464swapper/0: do_initcall_level+0xdc/0x1b0swapper/0: do_initcalls+0x70/0xc0swapper/0: do_basic_setup+0x1c/0x28swapper/0: kernel_init_freeable+0x144/0x1b8swapper/0: kernel_init+0x20/0x1a8swapper/0: ret_from_fork+0x10/0x20==================================================================
POC
Reference
No PoCs from references.