| From foo@baz Wed 22 May 2019 06:53:31 PM CEST |
| From: YueHaibing <yuehaibing@huawei.com> |
| Date: Tue, 14 May 2019 22:55:32 +0800 |
| Subject: ppp: deflate: Fix possible crash in deflate_init |
| |
| From: YueHaibing <yuehaibing@huawei.com> |
| |
| [ Upstream commit 3ebe1bca58c85325c97a22d4fc3f5b5420752e6f ] |
| |
| BUG: unable to handle kernel paging request at ffffffffa018f000 |
| PGD 3270067 P4D 3270067 PUD 3271063 PMD 2307eb067 PTE 0 |
| Oops: 0000 [#1] PREEMPT SMP |
| CPU: 0 PID: 4138 Comm: modprobe Not tainted 5.1.0-rc7+ #1 |
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS |
| rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 |
| RIP: 0010:ppp_register_compressor+0x3e/0xd0 [ppp_generic] |
| Code: 98 4a 3f e2 48 8b 15 c1 67 00 00 41 8b 0c 24 48 81 fa 40 f0 19 a0 |
| 75 0e eb 35 48 8b 12 48 81 fa 40 f0 19 a0 74 |
| RSP: 0018:ffffc90000d93c68 EFLAGS: 00010287 |
| RAX: ffffffffa018f000 RBX: ffffffffa01a3000 RCX: 000000000000001a |
| RDX: ffff888230c750a0 RSI: 0000000000000000 RDI: ffffffffa019f000 |
| RBP: ffffc90000d93c80 R08: 0000000000000001 R09: 0000000000000000 |
| R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0194080 |
| R13: ffff88822ee1a700 R14: 0000000000000000 R15: ffffc90000d93e78 |
| FS: 00007f2339557540(0000) GS:ffff888237a00000(0000) |
| knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 |
| CR2: ffffffffa018f000 CR3: 000000022bde4000 CR4: 00000000000006f0 |
| Call Trace: |
| ? 0xffffffffa01a3000 |
| deflate_init+0x11/0x1000 [ppp_deflate] |
| ? 0xffffffffa01a3000 |
| do_one_initcall+0x6c/0x3cc |
| ? kmem_cache_alloc_trace+0x248/0x3b0 |
| do_init_module+0x5b/0x1f1 |
| load_module+0x1db1/0x2690 |
| ? m_show+0x1d0/0x1d0 |
| __do_sys_finit_module+0xc5/0xd0 |
| __x64_sys_finit_module+0x15/0x20 |
| do_syscall_64+0x6b/0x1d0 |
| entry_SYSCALL_64_after_hwframe+0x49/0xbe |
| |
| If ppp_deflate fails to register in deflate_init, |
| module initialization failed out, however |
| ppp_deflate_draft may has been regiestred and not |
| unregistered before return. |
| Then the seconed modprobe will trigger crash like this. |
| |
| Reported-by: Hulk Robot <hulkci@huawei.com> |
| Signed-off-by: YueHaibing <yuehaibing@huawei.com> |
| Acked-by: Guillaume Nault <gnault@redhat.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/ppp/ppp_deflate.c | 20 ++++++++++++++------ |
| 1 file changed, 14 insertions(+), 6 deletions(-) |
| |
| --- a/drivers/net/ppp/ppp_deflate.c |
| +++ b/drivers/net/ppp/ppp_deflate.c |
| @@ -610,12 +610,20 @@ static struct compressor ppp_deflate_dra |
| |
| static int __init deflate_init(void) |
| { |
| - int answer = ppp_register_compressor(&ppp_deflate); |
| - if (answer == 0) |
| - printk(KERN_INFO |
| - "PPP Deflate Compression module registered\n"); |
| - ppp_register_compressor(&ppp_deflate_draft); |
| - return answer; |
| + int rc; |
| + |
| + rc = ppp_register_compressor(&ppp_deflate); |
| + if (rc) |
| + return rc; |
| + |
| + rc = ppp_register_compressor(&ppp_deflate_draft); |
| + if (rc) { |
| + ppp_unregister_compressor(&ppp_deflate); |
| + return rc; |
| + } |
| + |
| + pr_info("PPP Deflate Compression module registered\n"); |
| + return 0; |
| } |
| |
| static void __exit deflate_cleanup(void) |