title: gtp: fix use-after-free and null-ptr-deref in gtp_genl_dump_pdp()
description: In the Linux kernel, the following vulnerability has been resolved:
gtp: fix use-after-free and null-ptr-deref in gtp_genl_dump_pdp()
The gtp_net_ops pernet operations structure for the subsystem must be
registered before registering the generic netlink family.
Syzkaller hit 'general protection fault in gtp_genl_dump_pdp' bug:
general protection fault, probably for non-canonical address
0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 1 PID: 5826 Comm: gtp Not tainted 6.8.0-rc3-std-def-alt1 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-alt1 04/01/2014
RIP: 0010:gtp_genl_dump_pdp+0x1be/0x800 [gtp]
Code: c6 89 c6 e8 64 e9 86 df 58 45 85 f6 0f 85 4e 04 00 00 e8 c5 ee 86
df 48 8b 54 24 18 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80>
3c 02 00 0f 85 de 05 00 00 48 8b 44 24 18 4c 8b 30 4c 39 f0 74
RSP: 0018:ffff888014107220 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88800fcda588 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f1be4eb05c0(0000) GS:ffff88806ce80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1be4e766cf CR3: 000000000c33e000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? show_regs+0x90/0xa0
? die_addr+0x50/0xd0
? exc_general_protection+0x148/0x220
? asm_exc_general_protection+0x22/0x30
? gtp_genl_dump_pdp+0x1be/0x800 [gtp]
? __alloc_skb+0x1dd/0x350
? __pfx___alloc_skb+0x10/0x10
genl_dumpit+0x11d/0x230
netlink_dump+0x5b9/0xce0
? lockdep_hardirqs_on_prepare+0x253/0x430
? __pfx_netlink_dump+0x10/0x10
? kasan_save_track+0x10/0x40
? __kasan_kmalloc+0x9b/0xa0
? genl_start+0x675/0x970
__netlink_dump_start+0x6fc/0x9f0
genl_family_rcv_msg_dumpit+0x1bb/0x2d0
? __pfx_genl_family_rcv_msg_dumpit+0x10/0x10
? genl_op_from_small+0x2a/0x440
? cap_capable+0x1d0/0x240
? __pfx_genl_start+0x10/0x10
? __pfx_genl_dumpit+0x10/0x10
? __pfx_genl_done+0x10/0x10
? security_capable+0x9d/0xe0
affected:
{
product: Linux
vendor: Linux
defaultStatus: unaffected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 459aa660eb1d, lessThan: f0ecdfa67918, status: affected, versionType: git
version: 459aa660eb1d, lessThan: f8cbd1791900, status: affected, versionType: git
version: 459aa660eb1d, lessThan: 2e534fd15e5c, status: affected, versionType: git
version: 459aa660eb1d, lessThan: a576308800be, status: affected, versionType: git
version: 459aa660eb1d, lessThan: 3963f16cc764, status: affected, versionType: git
version: 459aa660eb1d, lessThan: ba6b8b02a331, status: affected, versionType: git
version: 459aa660eb1d, lessThan: 5013bd54d283, status: affected, versionType: git
version: 459aa660eb1d, lessThan: 136cfaca2256, status: affected, versionType: git
}
{
product: Linux
vendor: Linux
defaultStatus: affected
repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
versions:
version: 4.7, status: affected
version: 0, lessThan: 4.7, status: unaffected, versionType: custom
version: 4.19.308, lessThanOrEqual: 4.19.*, status: unaffected, versionType: custom
version: 5.4.270, lessThanOrEqual: 5.4.*, status: unaffected, versionType: custom
version: 5.10.211, lessThanOrEqual: 5.10.*, status: unaffected, versionType: custom
version: 5.15.150, lessThanOrEqual: 5.15.*, status: unaffected, versionType: custom
version: 6.1.80, lessThanOrEqual: 6.1.*, status: unaffected, versionType: custom
version: 6.6.19, lessThanOrEqual: 6.6.*, status: unaffected, versionType: custom
version: 6.7.7, lessThanOrEqual: 6.7.*, status: unaffected, versionType: custom
version: 6.8, lessThanOrEqual: *, status: unaffected, versionType: original_commit_for_fix
}
