In the Linux kernel, the following vulnerability has been resolved:

mm/vmalloc: fix data race in shownumainfo()

The following data-race was found in shownumainfo():

================================================================== BUG: KCSAN: data-race in vmallocinfoshow / vmallocinfoshow

read to 0xffff88800971fe30 of 4 bytes by task 8289 on cpu 0: shownumainfo mm/vmalloc.c:4936 [inline] vmallocinfoshow+0x5a8/0x7e0 mm/vmalloc.c:5016 seqreaditer+0x373/0xb40 fs/seqfile.c:230 procregreaditer+0x11e/0x170 fs/proc/inode.c:299 ....

write to 0xffff88800971fe30 of 4 bytes by task 8287 on cpu 1: shownumainfo mm/vmalloc.c:4934 [inline] vmallocinfoshow+0x38f/0x7e0 mm/vmalloc.c:5016 seqreaditer+0x373/0xb40 fs/seqfile.c:230 procregreaditer+0x11e/0x170 fs/proc/inode.c:299 ....

value changed: 0x0000008f -> 0x00000000

According to this report,there is a read/write data-race because m->private is accessible to multiple CPUs. To fix this, instead of allocating the heap in procvmallocinit() and passing the heap address to m->private, vmallocinfoshow() should allocate the heap.