| Message ID | 20241212222247.724674-1-edumazet@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 429fde2d81bcef0ebab002215358955704586457 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] net: tun: fix tun_napi_alloc_frags() | expand |
On Thu, Dec 12, 2024 at 10:22:47PM +0000, Eric Dumazet wrote: > syzbot reported the following crash [1] > > Issue came with the blamed commit. Instead of going through > all the iov components, we keep using the first one > and end up with a malformed skb. [...] > > Fixes: de4f5fed3f23 ("iov_iter: add iter_iovec() helper") > Reported-by: syzbot+4f66250f6663c0c1d67e@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/netdev/675b61aa.050a0220.599f4.00bb.GAE@google.com/T/#u > Cc: stable@vger.kernel.org > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Jens Axboe <axboe@kernel.dk> > --- > drivers/net/tun.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index d7a865ef370b6968c095510ae16b5196e30e54b9..e816aaba8e5f2ed06f8832f79553b6c976e75bb8 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -1481,7 +1481,7 @@ static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, > skb->truesize += skb->data_len; > > for (i = 1; i < it->nr_segs; i++) { > - const struct iovec *iov = iter_iov(it); > + const struct iovec *iov = iter_iov(it) + i; > size_t fragsz = iov->iov_len; > struct page *page; > void *frag; > -- Reviewed-by: Joe Damato <jdamato@fastly.com>
Oops, thanks for the fix:
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Eric Dumazet wrote: > syzbot reported the following crash [1] > > Issue came with the blamed commit. Instead of going through > all the iov components, we keep using the first one > and end up with a malformed skb. > > [1] > > kernel BUG at net/core/skbuff.c:2849 ! > Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI > CPU: 0 UID: 0 PID: 6230 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00407-g96b6fcc0ee41 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 > RIP: 0010:__pskb_pull_tail+0x1568/0x1570 net/core/skbuff.c:2848 > Code: 38 c1 0f 8c 32 f1 ff ff 4c 89 f7 e8 92 96 74 f8 e9 25 f1 ff ff e8 e8 ae 09 f8 48 8b 5c 24 08 e9 eb fb ff ff e8 d9 ae 09 f8 90 <0f> 0b 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 > RSP: 0018:ffffc90004cbef30 EFLAGS: 00010293 > RAX: ffffffff8995c347 RBX: 00000000fffffff2 RCX: ffff88802cf45a00 > RDX: 0000000000000000 RSI: 00000000fffffff2 RDI: 0000000000000000 > RBP: ffff88807df0c06a R08: ffffffff8995b084 R09: 1ffff1100fbe185c > R10: dffffc0000000000 R11: ffffed100fbe185d R12: ffff888076e85d50 > R13: ffff888076e85c80 R14: ffff888076e85cf4 R15: ffff888076e85c80 > FS: 00007f0dca6ea6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f0dca6ead58 CR3: 00000000119da000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > skb_cow_data+0x2da/0xcb0 net/core/skbuff.c:5284 > tipc_aead_decrypt net/tipc/crypto.c:894 [inline] > tipc_crypto_rcv+0x402/0x24e0 net/tipc/crypto.c:1844 > tipc_rcv+0x57e/0x12a0 net/tipc/node.c:2109 > tipc_l2_rcv_msg+0x2bd/0x450 net/tipc/bearer.c:668 > __netif_receive_skb_list_ptype net/core/dev.c:5720 [inline] > __netif_receive_skb_list_core+0x8b7/0x980 net/core/dev.c:5762 > __netif_receive_skb_list net/core/dev.c:5814 [inline] > netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 > gro_normal_list include/net/gro.h:515 [inline] > napi_complete_done+0x2b5/0x870 net/core/dev.c:6256 > napi_complete include/linux/netdevice.h:567 [inline] > tun_get_user+0x2ea0/0x4890 drivers/net/tun.c:1982 > tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2057 > do_iter_readv_writev+0x600/0x880 > vfs_writev+0x376/0xba0 fs/read_write.c:1050 > do_writev+0x1b6/0x360 fs/read_write.c:1096 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > Fixes: de4f5fed3f23 ("iov_iter: add iter_iovec() helper") > Reported-by: syzbot+4f66250f6663c0c1d67e@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/netdev/675b61aa.050a0220.599f4.00bb.GAE@google.com/T/#u > Cc: stable@vger.kernel.org > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Jens Axboe <axboe@kernel.dk> Acked-by: Willem de Bruijn <willemb@google.com>
On Thu, Dec 12, 2024 at 10:22:47PM +0000, Eric Dumazet wrote: > syzbot reported the following crash [1] > > Issue came with the blamed commit. Instead of going through > all the iov components, we keep using the first one > and end up with a malformed skb. > > [1] > > kernel BUG at net/core/skbuff.c:2849 ! > Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI > CPU: 0 UID: 0 PID: 6230 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00407-g96b6fcc0ee41 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 > RIP: 0010:__pskb_pull_tail+0x1568/0x1570 net/core/skbuff.c:2848 > Code: 38 c1 0f 8c 32 f1 ff ff 4c 89 f7 e8 92 96 74 f8 e9 25 f1 ff ff e8 e8 ae 09 f8 48 8b 5c 24 08 e9 eb fb ff ff e8 d9 ae 09 f8 90 <0f> 0b 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 > RSP: 0018:ffffc90004cbef30 EFLAGS: 00010293 > RAX: ffffffff8995c347 RBX: 00000000fffffff2 RCX: ffff88802cf45a00 > RDX: 0000000000000000 RSI: 00000000fffffff2 RDI: 0000000000000000 > RBP: ffff88807df0c06a R08: ffffffff8995b084 R09: 1ffff1100fbe185c > R10: dffffc0000000000 R11: ffffed100fbe185d R12: ffff888076e85d50 > R13: ffff888076e85c80 R14: ffff888076e85cf4 R15: ffff888076e85c80 > FS: 00007f0dca6ea6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f0dca6ead58 CR3: 00000000119da000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > skb_cow_data+0x2da/0xcb0 net/core/skbuff.c:5284 > tipc_aead_decrypt net/tipc/crypto.c:894 [inline] > tipc_crypto_rcv+0x402/0x24e0 net/tipc/crypto.c:1844 > tipc_rcv+0x57e/0x12a0 net/tipc/node.c:2109 > tipc_l2_rcv_msg+0x2bd/0x450 net/tipc/bearer.c:668 > __netif_receive_skb_list_ptype net/core/dev.c:5720 [inline] > __netif_receive_skb_list_core+0x8b7/0x980 net/core/dev.c:5762 > __netif_receive_skb_list net/core/dev.c:5814 [inline] > netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 > gro_normal_list include/net/gro.h:515 [inline] > napi_complete_done+0x2b5/0x870 net/core/dev.c:6256 > napi_complete include/linux/netdevice.h:567 [inline] > tun_get_user+0x2ea0/0x4890 drivers/net/tun.c:1982 > tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2057 > do_iter_readv_writev+0x600/0x880 > vfs_writev+0x376/0xba0 fs/read_write.c:1050 > do_writev+0x1b6/0x360 fs/read_write.c:1096 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > Fixes: de4f5fed3f23 ("iov_iter: add iter_iovec() helper") > Reported-by: syzbot+4f66250f6663c0c1d67e@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/netdev/675b61aa.050a0220.599f4.00bb.GAE@google.com/T/#u > Cc: stable@vger.kernel.org > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Jens Axboe <axboe@kernel.dk> Acked-by: Michael S. Tsirkin <mst@redhat.com> > --- > drivers/net/tun.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index d7a865ef370b6968c095510ae16b5196e30e54b9..e816aaba8e5f2ed06f8832f79553b6c976e75bb8 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -1481,7 +1481,7 @@ static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, > skb->truesize += skb->data_len; > > for (i = 1; i < it->nr_segs; i++) { > - const struct iovec *iov = iter_iov(it); > + const struct iovec *iov = iter_iov(it) + i; > size_t fragsz = iov->iov_len; > struct page *page; > void *frag; > -- > 2.47.1.613.gc27f4b7a9f-goog >
Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski <kuba@kernel.org>: On Thu, 12 Dec 2024 22:22:47 +0000 you wrote: > syzbot reported the following crash [1] > > Issue came with the blamed commit. Instead of going through > all the iov components, we keep using the first one > and end up with a malformed skb. > > [1] > > [...] Here is the summary with links: - [net] net: tun: fix tun_napi_alloc_frags() https://git.kernel.org/netdev/net/c/429fde2d81bc You are awesome, thank you!
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index d7a865ef370b6968c095510ae16b5196e30e54b9..e816aaba8e5f2ed06f8832f79553b6c976e75bb8 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1481,7 +1481,7 @@ static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, skb->truesize += skb->data_len; for (i = 1; i < it->nr_segs; i++) { - const struct iovec *iov = iter_iov(it); + const struct iovec *iov = iter_iov(it) + i; size_t fragsz = iov->iov_len; struct page *page; void *frag;
syzbot reported the following crash [1] Issue came with the blamed commit. Instead of going through all the iov components, we keep using the first one and end up with a malformed skb. [1] kernel BUG at net/core/skbuff.c:2849 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 6230 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00407-g96b6fcc0ee41 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:__pskb_pull_tail+0x1568/0x1570 net/core/skbuff.c:2848 Code: 38 c1 0f 8c 32 f1 ff ff 4c 89 f7 e8 92 96 74 f8 e9 25 f1 ff ff e8 e8 ae 09 f8 48 8b 5c 24 08 e9 eb fb ff ff e8 d9 ae 09 f8 90 <0f> 0b 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90004cbef30 EFLAGS: 00010293 RAX: ffffffff8995c347 RBX: 00000000fffffff2 RCX: ffff88802cf45a00 RDX: 0000000000000000 RSI: 00000000fffffff2 RDI: 0000000000000000 RBP: ffff88807df0c06a R08: ffffffff8995b084 R09: 1ffff1100fbe185c R10: dffffc0000000000 R11: ffffed100fbe185d R12: ffff888076e85d50 R13: ffff888076e85c80 R14: ffff888076e85cf4 R15: ffff888076e85c80 FS: 00007f0dca6ea6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0dca6ead58 CR3: 00000000119da000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_cow_data+0x2da/0xcb0 net/core/skbuff.c:5284 tipc_aead_decrypt net/tipc/crypto.c:894 [inline] tipc_crypto_rcv+0x402/0x24e0 net/tipc/crypto.c:1844 tipc_rcv+0x57e/0x12a0 net/tipc/node.c:2109 tipc_l2_rcv_msg+0x2bd/0x450 net/tipc/bearer.c:668 __netif_receive_skb_list_ptype net/core/dev.c:5720 [inline] __netif_receive_skb_list_core+0x8b7/0x980 net/core/dev.c:5762 __netif_receive_skb_list net/core/dev.c:5814 [inline] netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x2b5/0x870 net/core/dev.c:6256 napi_complete include/linux/netdevice.h:567 [inline] tun_get_user+0x2ea0/0x4890 drivers/net/tun.c:1982 tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2057 do_iter_readv_writev+0x600/0x880 vfs_writev+0x376/0xba0 fs/read_write.c:1050 do_writev+0x1b6/0x360 fs/read_write.c:1096 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: de4f5fed3f23 ("iov_iter: add iter_iovec() helper") Reported-by: syzbot+4f66250f6663c0c1d67e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/675b61aa.050a0220.599f4.00bb.GAE@google.com/T/#u Cc: stable@vger.kernel.org Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jens Axboe <axboe@kernel.dk> --- drivers/net/tun.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)