test kernel BUG in add_grec

[Tadeusz Struk]

#syz test: https://android.googlesource.com/kernel/common android12-5.10
======================================
index c2f8e69d7d7a..9b5d2d87f836 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1650,6 +1650,13 @@ static int __ip6_append_data(struct sock *sk,
err = -EINVAL;
goto error;
}
+ if (unlikely(alloclen < fraglen)) {
+ if (printk_ratelimit())
+ pr_warn("%s: wrong alloclen: %d,
fraglen: %d",
+ __func__, alloclen, fraglen);
+ alloclen = fraglen;
+ }
+
if (transhdrlen) {
skb = sock_alloc_send_skb(sk, alloclen,
(flags & MSG_DONTWAIT), &err);

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

net/ipv6/ip6_output.c:1655:48: warning: missing terminating '"' character [-Winvalid-pp-token]
net/ipv6/ip6_output.c:1655:48: error: expected ')'


Tested on:

commit: a817d6ed ANDROID: mm: Fix page table lookup in specula..
git tree: https://android.googlesource.com/kernel/common android12-5.10
dashboard link: https://syzkaller.appspot.com/bug?extid=e223cf47ec8ae183f2a0
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=11695879700000

[Tadeusz Struk]

#syz test: https://android.googlesource.com/kernel/common android12-5.10

===================================================
index 4788f6b37053..622345af323e 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1629,6 +1629,13 @@ static int __ip6_append_data(struct sock *sk,

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+e223cf...@syzkaller.appspotmail.com

Tested on:

commit: fcaaaaae UPSTREAM: mac80211_hwsim: initialize ieee8021..

git tree: https://android.googlesource.com/kernel/common android12-5.10

kernel config: https://syzkaller.appspot.com/x/.config?x=c346f7c7af5fc789

dashboard link: https://syzkaller.appspot.com/bug?extid=e223cf47ec8ae183f2a0
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=15f819ee700000

Note: testing is done by a robot and is best-effort only.

[Tadeusz Struk]

#syz fix: net: ipv6: fix skb_over_panic in __ip6_append_data

[Tadeusz Struk]

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+e223cf...@syzkaller.appspotmail.com

Tested on:

commit: a04b1bf5 Merge tag 'for-5.18/parisc-1' of git://git.ke..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
kernel config: https://syzkaller.appspot.com/x/.config?x=d5bd73a9bb304adc

dashboard link: https://syzkaller.appspot.com/bug?extid=e223cf47ec8ae183f2a0
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.