assertion failed: buf == buf_end

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 0125d68f9264 Unset CC for apps-install makes
git tree: https://github.com/akaros/akaros.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=111ad231400000
kernel config: https://syzkaller.appspot.com/x/.config?x=bc709c3b83482973
dashboard link: https://syzkaller.appspot.com/bug?extid=7a8e2903ce1233ffcd3d
compiler:

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+7a8e29...@syzkaller.appspotmail.com

kernel panic at kern/src/ns/fs_file.c:431, from core 1: assertion failed:
buf == buf_end
Stack Backtrace on Core 1:
#01 [<0xffffffffc200a33c>] in backtrace at src/kdebug.c:220
#02 [<0xffffffffc2009b3d>] in _panic at src/init.c:268
#03 [<0xffffffffc20390fb>] in fs_file_write at src/ns/fs_file.c:431
#04 [<0xffffffffc2044086>] in tree_chan_write at src/ns/tree_file.c:1014
#05 [<0xffffffffc2040321>] in rwrite at src/ns/sysfile.c:1122
#06 [<0xffffffffc204053b>] in syswrite at src/ns/sysfile.c:1140
#07 [<0xffffffffc2056021>] in sys_write at src/syscall.c:1704
#08 [<0xffffffffc2059579>] in syscall at src/syscall.c:2455
#09 [<0xffffffffc2059744>] in run_local_syscall at src/syscall.c:2490
#10 [<0xffffffffc2059c79>] in prep_syscalls at src/syscall.c:2510
#11 [<0xffffffffc20ab5fa>] in sysenter_callwrapper at arch/x86/trap.c:854


---
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: f89b6d306593 alarm: Do not allow callbacks to block

git tree: https://github.com/akaros/akaros.git master

console output: https://syzkaller.appspot.com/x/log.txt?x=173dd093400000

kernel config: https://syzkaller.appspot.com/x/.config?x=bc709c3b83482973
dashboard link: https://syzkaller.appspot.com/bug?extid=7a8e2903ce1233ffcd3d
compiler:

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=104da225400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=142b02b9400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+7a8e29...@syzkaller.appspotmail.com

kernel panic at kern/src/ns/fs_file.c:431, from core 0: assertion failed:
buf == buf_end
Stack Backtrace on Core 0:
#01 [<0xffffffffc200a33c>] in backtrace at src/kdebug.c:229
#02 [<0xffffffffc2009acd>] in _panic at src/init.c:267
#03 [<0xffffffffc203915b>] in fs_file_write at src/ns/fs_file.c:431
#04 [<0xffffffffc20440d6>] in tree_chan_write at src/ns/tree_file.c:1014
#05 [<0xffffffffc2040371>] in rwrite at src/ns/sysfile.c:1124
#06 [<0xffffffffc204058b>] in syswrite at src/ns/sysfile.c:1142
#07 [<0xffffffffc2056951>] in sys_write at src/syscall.c:1704
#08 [<0xffffffffc2059f09>] in syscall at src/syscall.c:2465
#09 [<0xffffffffc205a0d4>] in run_local_syscall at src/syscall.c:2500
#10 [<0xffffffffc205a609>] in prep_syscalls at src/syscall.c:2520
#11 [<0xffffffffc20abc0a>] in sysenter_callwrapper at arch/x86/trap.c:854