Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 3 Jan 2024 22:16:13 +0800 | Subject | Re: [syzbot] [mm?] WARNING in __folio_rmap_sanity_checks | From | "Yin, Fengwei" <> |
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On 1/3/2024 8:13 PM, David Hildenbrand wrote: > On 03.01.24 12:48, syzbot wrote: >> Hello, >> >> syzbot found the following issue on: >> >> HEAD commit: ab0b3e6ef50d Add linux-next specific files for 20240102 >> git tree: linux-next >> console+strace: https://syzkaller.appspot.com/x/log.txt?x=17be3e09e80000 >> kernel config: >> https://syzkaller.appspot.com/x/.config?x=a14a6350374945f9 >> dashboard link: >> https://syzkaller.appspot.com/bug?extid=50ef73537bbc393a25bb >> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils >> for Debian) 2.40 >> syz repro: >> https://syzkaller.appspot.com/x/repro.syz?x=14e2256ee80000 >> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17b57db5e80000 >> >> Downloadable assets: >> disk image: >> https://storage.googleapis.com/syzbot-assets/4e6376fe5764/disk-ab0b3e6e.raw.xz >> vmlinux: >> https://storage.googleapis.com/syzbot-assets/7cb9ecbaf001/vmlinux-ab0b3e6e.xz >> kernel image: >> https://storage.googleapis.com/syzbot-assets/2c1a9a6d424f/bzImage-ab0b3e6e.xz >> >> The issue was bisected to: >> >> commit 68f0320824fa59c5429cbc811e6c46e7a30ea32c >> Author: David Hildenbrand <david@redhat.com> >> Date: Wed Dec 20 22:44:31 2023 +0000 >> >> mm/rmap: convert folio_add_file_rmap_range() into >> folio_add_file_rmap_[pte|ptes|pmd]() >> >> bisection log: >> https://syzkaller.appspot.com/x/bisect.txt?x=10b9e1b1e80000 >> final oops: >> https://syzkaller.appspot.com/x/report.txt?x=12b9e1b1e80000 >> console output: https://syzkaller.appspot.com/x/log.txt?x=14b9e1b1e80000 >> >> IMPORTANT: if you fix the issue, please add the following tag to the >> commit: >> Reported-by: syzbot+50ef73537bbc393a25bb@syzkaller.appspotmail.com >> Fixes: 68f0320824fa ("mm/rmap: convert folio_add_file_rmap_range() >> into folio_add_file_rmap_[pte|ptes|pmd]()") >> >> kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:283 >> __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:324 >> kasan_slab_alloc include/linux/kasan.h:201 [inline] >> slab_post_alloc_hook mm/slub.c:3813 [inline] >> slab_alloc_node mm/slub.c:3860 [inline] >> kmem_cache_alloc+0x136/0x320 mm/slub.c:3867 >> vm_area_alloc+0x1f/0x220 kernel/fork.c:465 >> mmap_region+0x3ae/0x2a90 mm/mmap.c:2804 >> do_mmap+0x890/0xef0 mm/mmap.c:1379 >> vm_mmap_pgoff+0x1a7/0x3c0 mm/util.c:573 >> ksys_mmap_pgoff+0x421/0x5a0 mm/mmap.c:1425 >> __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline] >> __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] >> __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:86 >> do_syscall_x64 arch/x86/entry/common.c:52 [inline] >> do_syscall_64+0xd0/0x250 arch/x86/entry/common.c:83 >> entry_SYSCALL_64_after_hwframe+0x62/0x6a >> ------------[ cut here ]------------ >> WARNING: CPU: 1 PID: 5059 at include/linux/rmap.h:202 >> __folio_rmap_sanity_checks+0x4d5/0x630 include/linux/rmap.h:202 >> Modules linked in: >> CPU: 1 PID: 5059 Comm: syz-executor115 Not tainted >> 6.7.0-rc8-next-20240102-syzkaller #0 >> Hardware name: Google Google Compute Engine/Google Compute Engine, >> BIOS Google 11/17/2023 >> RIP: 0010:__folio_rmap_sanity_checks+0x4d5/0x630 include/linux/rmap.h:202 >> Code: 41 83 e4 01 44 89 e6 e8 79 bc b7 ff 45 84 e4 0f 85 08 fc ff ff >> e8 3b c1 b7 ff 48 c7 c6 e0 b5 d9 8a 48 89 df e8 5c 12 f7 ff 90 <0f> 0b >> 90 e9 eb fb ff ff e8 1e c1 b7 ff be 01 00 00 00 48 89 df e8 >> RSP: 0018:ffffc900038df978 EFLAGS: 00010293 >> RAX: 0000000000000000 RBX: ffffea00008cde00 RCX: ffffffff81687419 >> RDX: ffff88807becbb80 RSI: ffffffff81d06104 RDI: 0000000000000000 >> RBP: ffffea00008cde00 R08: 0000000000000000 R09: fffffbfff1e75f6a >> R10: ffffffff8f3afb57 R11: 0000000000000001 R12: 0000000000000000 >> R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000000 >> FS: 0000555556508380(0000) GS:ffff8880b9900000(0000) >> knlGS:0000000000000000 >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> CR2: 00000000200000c0 CR3: 0000000079000000 CR4: 00000000003506f0 >> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >> Call Trace: >> <TASK> >> __folio_add_rmap mm/rmap.c:1167 [inline] >> __folio_add_file_rmap mm/rmap.c:1452 [inline] >> folio_add_file_rmap_ptes+0x8e/0x2c0 mm/rmap.c:1478 >> insert_page_into_pte_locked.isra.0+0x34d/0x960 mm/memory.c:1874 >> insert_page mm/memory.c:1900 [inline] >> vm_insert_page+0x62c/0x8c0 mm/memory.c:2053 >> packet_mmap+0x314/0x570 net/packet/af_packet.c:4594 >> call_mmap include/linux/fs.h:2090 [inline] >> mmap_region+0x745/0x2a90 mm/mmap.c:2819 >> do_mmap+0x890/0xef0 mm/mmap.c:1379 >> vm_mmap_pgoff+0x1a7/0x3c0 mm/util.c:573 >> ksys_mmap_pgoff+0x421/0x5a0 mm/mmap.c:1425 >> __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline] >> __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] >> __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:86 >> do_syscall_x64 arch/x86/entry/common.c:52 [inline] >> do_syscall_64+0xd0/0x250 arch/x86/entry/common.c:83 >> entry_SYSCALL_64_after_hwframe+0x62/0x6a > > If I am not wrong, that triggers: > > VM_WARN_ON_FOLIO(folio_test_large(folio) && > !folio_test_large_rmappable(folio), folio); > > So we are trying to rmap a large folio that did not go through > folio_prep_large_rmappable(). > > net/packet/af_packet.c calls vm_insert_page() on some pages/folios stoed > in the "struct packet_ring_buffer". No idea where that comes from, but I > suspect it's simply some compound allocation. Looks like: alloc_pg_vec alloc_one_pg_vec_page gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
buffer = (char *) __get_free_pages(gfp_flags, order); So you are right here... :).
Regards Yin, Fengwei
> > Likely, rmap handling is completely bogus for these folios? >
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