CVE-2024-53097

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> mm: krealloc: Fix MTE false alarm in __do_krealloc<br /> <br /> This patch addresses an issue introduced by commit 1a83a716ec233 ("mm:<br /> krealloc: consider spare memory for __GFP_ZERO") which causes MTE<br /> (Memory Tagging Extension) to falsely report a slab-out-of-bounds error.<br /> <br /> The problem occurs when zeroing out spare memory in __do_krealloc. The<br /> original code only considered software-based KASAN and did not account<br /> for MTE. It does not reset the KASAN tag before calling memset, leading<br /> to a mismatch between the pointer tag and the memory tag, resulting<br /> in a false positive.<br /> <br /> Example of the error:<br /> ==================================================================<br /> swapper/0: BUG: KASAN: slab-out-of-bounds in __memset+0x84/0x188<br /> swapper/0: Write at addr f4ffff8005f0fdf0 by task swapper/0/1<br /> swapper/0: Pointer tag: [f4], memory tag: [fe]<br /> swapper/0:<br /> swapper/0: CPU: 4 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.<br /> swapper/0: Hardware name: MT6991(ENG) (DT)<br /> swapper/0: Call trace:<br /> swapper/0: dump_backtrace+0xfc/0x17c<br /> swapper/0: show_stack+0x18/0x28<br /> swapper/0: dump_stack_lvl+0x40/0xa0<br /> swapper/0: print_report+0x1b8/0x71c<br /> swapper/0: kasan_report+0xec/0x14c<br /> swapper/0: __do_kernel_fault+0x60/0x29c<br /> swapper/0: do_bad_area+0x30/0xdc<br /> swapper/0: do_tag_check_fault+0x20/0x34<br /> swapper/0: do_mem_abort+0x58/0x104<br /> swapper/0: el1_abort+0x3c/0x5c<br /> swapper/0: el1h_64_sync_handler+0x80/0xcc<br /> swapper/0: el1h_64_sync+0x68/0x6c<br /> swapper/0: __memset+0x84/0x188<br /> swapper/0: btf_populate_kfunc_set+0x280/0x3d8<br /> swapper/0: __register_btf_kfunc_id_set+0x43c/0x468<br /> swapper/0: register_btf_kfunc_id_set+0x48/0x60<br /> swapper/0: register_nf_nat_bpf+0x1c/0x40<br /> swapper/0: nf_nat_init+0xc0/0x128<br /> swapper/0: do_one_initcall+0x184/0x464<br /> swapper/0: do_initcall_level+0xdc/0x1b0<br /> swapper/0: do_initcalls+0x70/0xc0<br /> swapper/0: do_basic_setup+0x1c/0x28<br /> swapper/0: kernel_init_freeable+0x144/0x1b8<br /> swapper/0: kernel_init+0x20/0x1a8<br /> swapper/0: ret_from_fork+0x10/0x20<br /> ==================================================================