On 8/16/21 12:58 PM, syzbot wrote:
Hello,
syzbot found the following issue on:
HEAD commit: 761c6d7ec820 Merge tag 'arc-5.14-rc6' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11d87ca1300000 kernel config: https://syzkaller.appspot.com/x/.config?x=730106bfb5bf8ace dashboard link: https://syzkaller.appspot.com/bug?extid=56fdf7f6291d819b9b19 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12ca6029300000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13bf42a1300000
The issue was bisected to:
commit 0ac1077e3a549bf8d35971613e2be05bdbb41a00 Author: Xin Long lucien.xin@gmail.com Date: Tue Oct 16 07:52:02 2018 +0000
sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL insteadbisection log: https://syzkaller.appspot.com/x/bisect.txt?x=16f311fa300000 final oops: https://syzkaller.appspot.com/x/report.txt?x=15f311fa300000 console output: https://syzkaller.appspot.com/x/log.txt?x=11f311fa300000
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+56fdf7f6291d819b9b19@syzkaller.appspotmail.com Fixes: 0ac1077e3a54 ("sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead")
------------[ cut here ]------------ WARNING: CPU: 1 PID: 8426 at mm/page_alloc.c:5366 __alloc_pages+0x588/0x5f0 mm/page_alloc.c:5413 Modules linked in: CPU: 1 PID: 8426 Comm: syz-executor477 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__alloc_pages+0x588/0x5f0 mm/page_alloc.c:5413 Code: 00 48 ba 00 00 00 00 00 fc ff df e9 5e fd ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 6d fd ff ff e8 bd 62 0a 00 e9 63 fd ff ff <0f> 0b 45 31 e4 e9 7a fd ff ff 48 8d 4c 24 50 80 e1 07 80 c1 03 38 RSP: 0018:ffffc90000fff9a0 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000014 RCX: 0000000000000000 RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc90000fffa28 RBP: ffffc90000fffaa8 R08: dffffc0000000000 R09: ffffc90000fffa00 R10: fffff520001fff45 R11: 0000000000000000 R12: 0000000000040d40 R13: ffffc90000fffa00 R14: 1ffff920001fff3c R15: 1ffff920001fff38 FS: 000000000148e300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa1e9a97740 CR3: 000000003406e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kmalloc_order+0x41/0x170 mm/slab_common.c:955 kmalloc_order_trace+0x15/0x70 mm/slab_common.c:971 kmalloc_large include/linux/slab.h:520 [inline] __kmalloc+0x292/0x390 mm/slub.c:4101 kmalloc include/linux/slab.h:596 [inline] kzalloc include/linux/slab.h:721 [inline] __v9fs_get_acl+0x40/0x110 fs/9p/acl.c:36 v9fs_get_acl+0xa5/0x290 fs/9p/acl.c:71
Looks like syzbot tries to mount malicious image. Easy fix just for thoughts:
diff --git a/fs/9p/acl.c b/fs/9p/acl.c index bb1b286c49ae..242a3bc7aaee 100644 --- a/fs/9p/acl.c +++ b/fs/9p/acl.c @@ -33,7 +33,7 @@ static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
size = v9fs_fid_xattr_get(fid, name, NULL, 0); if (size > 0) { - value = kzalloc(size, GFP_NOFS); + value = kzalloc(size, GFP_NOFS | __GFP_NOWARN); if (!value) return ERR_PTR(-ENOMEM); size = v9fs_fid_xattr_get(fid, name, value, size);
With regards, Pavel Skripkin