On Thu, Jun 20, 2019 at 09:30:49AM -0700, Zubin Mithra wrote:
> Hello,
>
> Syzkaller has triggered a kernel WARNING when fuzzing a 4.14 kernel with the following stacktrace.
> Call Trace:
> __dump_stack lib/dump_stack.c:17 [inline]
> dump_stack+0x114/0x1cf lib/dump_stack.c:53
> panic+0x1bb/0x3a0 kernel/panic.c:181
> __warn.cold.9+0x149/0x186 kernel/panic.c:542
> report_bug+0x1f7/0x272 lib/bug.c:186
> fixup_bug arch/x86/kernel/traps.c:177 [inline]
> do_error_trap+0x1c1/0x430 arch/x86/kernel/traps.c:295
> do_invalid_op+0x20/0x30 arch/x86/kernel/traps.c:314
> invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:944
> __remove_privs fs/inode.c:1805 [inline]
> file_remove_privs+0x291/0x4c0 fs/inode.c:1827
> __generic_file_write_iter+0x166/0x5b0 mm/filemap.c:3096
> blkdev_write_iter+0x1f5/0x3b0 fs/block_dev.c:1905
> call_write_iter include/linux/fs.h:1782 [inline]
> new_sync_write fs/read_write.c:471 [inline]
> __vfs_write+0x53f/0x7d0 fs/read_write.c:484
> vfs_write+0x18c/0x500 fs/read_write.c:546
> SYSC_write fs/read_write.c:593 [inline]
> SyS_write+0xf4/0x230 fs/read_write.c:585
> do_syscall_32_irqs_on arch/x86/entry/common.c:340 [inline]
> do_fast_syscall_32+0x3c1/0xbf1 arch/x86/entry/common.c:403
> entry_SYSENTER_compat+0x84/0x96 arch/x86/entry/entry_64_compat.S:139
>
>
> Could the following patch be applied to 5.0.y, 4.19.y, 4.14.y? The commit is present in 5.1.y.
> * f69e749a4935 ("Abort file_remove_privs() for non-reg. files")
5.0 is long end-of-life, but 4.19.y and 4.14.y is good. What about
older kernels? it seems to be applicable there too, right?
thanks,
greg k-h
