In the Linux kernel, the following vulnerability has been resolved: f2fs: fix null pointer panic in tracepoint in _replaceatomicwriteblock We got a kernel panic if oldaddr is NULL. https://bugzilla.kernel.org/showbug.cgi?id=217266 BUG: kernel NULL pointer dereference, address: 0000000000000000 Call Trace: <TASK> f2fscommitatomicwrite+0x619/0x990 [f2fs a1b985b80f5babd6f3ea778384908880812bfa43] _f2fsioctl+0xd8e/0x4080 [f2fs a1b985b80f5babd6f3ea778384908880812bfa43] ? vfswrite+0x2ae/0x3f0 ? vfswrite+0x2ae/0x3f0 _x64sysioctl+0x91/0xd0 dosyscall64+0x5c/0x90 entrySYSCALL64afterhwframe+0x72/0xdc RIP: 0033:0x7f69095fe53f