On Wed, Jan 24, 2024 at 11:14 AM kovalev@altlinux.org wrote:
From: Vasiliy Kovalev kovalev@altlinux.org
After unloading the module, an instance continues to exist that accesses outdated memory addresses.
To prevent this, the dump_pdp_en flag has been added, which blocks the dump of pdp contexts by a false value. And only after these checks can the net_generic() function be called.
These errors were found using the syzkaller program:
Syzkaller hit 'general protection fault in gtp_genl_dump_pdp' bug. gtp: GTP module loaded (pdp ctx size 104 bytes) gtp: GTP module unloaded general protection fault, probably for non-canonical address 0xdffffc0000000001:0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 PID: 2782 Comm: syz-executor139 Not tainted 5.10.200-std-def-alt1 #1
Oh wait, this is a 5.10 kernel ?
Please generate a stack trace using a recent tree, it is possible the bug has been fixed already.