mainlining shenanigans
nested target/match_revfn() calls work with xt[NFPROTO_UNSPEC] lists
without taking xt[NFPROTO_UNSPEC].mutex. This can race with module unload
and cause host to crash:
general protection fault: 0000 [#1]
Modules linked in: ... [last unloaded: xt_cluster]
CPU: 0 PID: 542455 Comm: iptables
RIP: 0010:[<ffffffff8ffbd518>] [<ffffffff8ffbd518>] strcmp+0x18/0x40
RDX: 0000000000000003 RSI: ffff9a5a5d9abe10 RDI: dead000000000111
R13: ffff9a5a5d9abe10 R14: ffff9a5a5d9abd8c R15: dead000000000100
(VvS: %R15 -- &xt_match, %RDI -- &xt_match.name,
xt_cluster unregister match in xt[NFPROTO_UNSPEC].match list)
Call Trace:
[<ffffffff902ccf44>] match_revfn+0x54/0xc0
[<ffffffff902ccf9f>] match_revfn+0xaf/0xc0
[<ffffffff902cd01e>] xt_find_revision+0x6e/0xf0
[<ffffffffc05a5be0>] do_ipt_get_ctl+0x100/0x420 [ip_tables]
[<ffffffff902cc6bf>] nf_getsockopt+0x4f/0x70
[<ffffffff902dd99e>] ip_getsockopt+0xde/0x100
[<ffffffff903039b5>] raw_getsockopt+0x25/0x50
[<ffffffff9026c5da>] sock_common_getsockopt+0x1a/0x20
[<ffffffff9026b89d>] SyS_getsockopt+0x7d/0xf0
[<ffffffff903cbf92>] system_call_fastpath+0x25/0x2a
Fixes:
|
||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.