** Also affects: linux (Ubuntu Artful) Importance: Undecided Status: New
** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu Artful) Importance: Undecided => Medium ** Changed in: linux (Ubuntu Artful) Status: New => In Progress ** Changed in: linux (Ubuntu) Status: Confirmed => Invalid ** Changed in: linux (Ubuntu Artful) Assignee: (unassigned) => Joseph Salisbury (jsalisbury) -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1772031 Title: kernel backtrace when receiving large UDP packages Status in linux package in Ubuntu: Invalid Status in linux source package in Artful: In Progress Bug description: kernel 4.13.0-41-generic is missing commit a90bcb86ae70: Author: Petar Penkov <ppen...@google.com> Date: Tue Aug 29 11:20:32 2017 -0700 iov_iter: fix page_copy_sane for compound pages Issue is that if the data crosses a page boundary inside a compound page, this check will incorrectly trigger a WARN_ON. To fix this, compute the order using the head of the compound page and adjust the offset to be relative to that head. Fixes: 72e809ed81ed ("iov_iter: sanity checks for copy to/from page primitives") Signed-off-by: Petar Penkov <ppen...@google.com> CC: Al Viro <v...@zeniv.linux.org.uk> CC: Eric Dumazet <eduma...@google.com> Signed-off-by: Al Viro <v...@zeniv.linux.org.uk> Commit 72e809ed81ed is in kernel 4.13.0-41-generic. As a result, when receiving large UDP packages with a small MTU we get backtraces like: [ 361.260969] ------------[ cut here ]------------ [ 361.260974] WARNING: CPU: 4 PID: 2541 at /build/linux-hwe-v6kHHF/linux-hwe-4.13.0/lib/iov_iter.c:693 copy_page_to_iter+0x194/0x2d0 [ 361.260975] Modules linked in: cmdlinepart sfc(OE) hwmon_vid crc32_generic mii rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace fscache 8021q garp mrp stp llc intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm i] [ 361.261002] CPU: 4 PID: 2541 Comm: udp_recv Tainted: G OE 4.13.0-39-generic #44~16.04.1-Ubuntu [ 361.261003] Hardware name: Dell Inc. PowerEdge R220/05Y15N, BIOS 1.4.0 10/23/2014 [ 361.261004] task: ffff91630b2bae80 task.stack: ffffbb19c2bfc000 [ 361.261005] RIP: 0010:copy_page_to_iter+0x194/0x2d0 [ 361.261006] RSP: 0018:ffffbb19c2bffc60 EFLAGS: 00010202 [ 361.261007] RAX: 0000000000001000 RBX: 00000000000000df RCX: 0017ffffc0000000 [ 361.261008] RDX: 00000000000000df RSI: 0000000000000f8e RDI: fffff666895279c0 [ 361.261009] RBP: ffffbb19c2bffca0 R08: 000000000000106d R09: 0000000000001024 [ 361.261009] R10: 0000000000000000 R11: ffff91630ccc9b00 R12: ffff91630d27a300 [ 361.261010] R13: ffffbb19c2bffde0 R14: 00000000000000df R15: 0000000000000175 [ 361.261011] FS: 00007fb8e7649700(0000) GS:ffff91631fd00000(0000) knlGS:0000000000000000 [ 361.261012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 361.261013] CR2: 000014588da85624 CR3: 000000024bad2002 CR4: 00000000001606e0 [ 361.261013] Call Trace: [ 361.261017] ? proto_init_net+0x40/0x40 [ 361.261019] skb_copy_datagram_iter+0x171/0x270 [ 361.261022] udp_recvmsg+0x108/0x490 [ 361.261024] inet_recvmsg+0x51/0xc0 [ 361.261026] sock_recvmsg+0x43/0x50 [ 361.261028] sock_read_iter+0x90/0xe0 [ 361.261030] new_sync_read+0xe2/0x130 [ 361.261032] __vfs_read+0x29/0x40 [ 361.261033] vfs_read+0x93/0x130 [ 361.261034] SyS_read+0x55/0xc0 [ 361.261037] entry_SYSCALL_64_fastpath+0x24/0xab [ 361.261038] RIP: 0033:0x7fb8e7160260 [ 361.261039] RSP: 002b:00007ffed9dd9e38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 361.261040] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb8e7160260 [ 361.261041] RDX: 000000000000ffe3 RSI: 00005622ad02f0a0 RDI: 0000000000000003 [ 361.261041] RBP: 00007ffed9dd9e70 R08: 0000000000000000 R09: 0000000000000011 [ 361.261042] R10: 0000000000000000 R11: 0000000000000246 R12: 00005622ace2e800 [ 361.261043] R13: 00007ffed9dd9f50 R14: 0000000000000000 R15: 0000000000000000 [ 361.261044] Code: de 4c 89 e7 e8 be fa ff ff 41 83 af a0 12 00 00 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 8b 4f 6c 48 d3 e0 e9 9d fe ff ff <0f> ff 48 83 c4 18 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 49 83 [ 361.261064] ---[ end trace c0b23bf37be9874d ]--- This is a request to pull in commit a90bcb86ae70. # lsb_release -rd Description: Ubuntu 17.10 Release: 17.10 # uname -a Linux c6320f 4.13.0-41-generic #46-Ubuntu SMP Wed May 2 13:38:30 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux # cat /proc/version_signature Ubuntu 4.13.0-41.46-generic 4.13.16 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1772031/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp