linux-stable.git/net/bpfilter, branch v4.18.2 Linux kernel stable tree bpfilter: include bpfilter_umh in assembly instead of using objcopy 2018-06-28T12:39:16+00:00 Masahiro Yamada yamada.masahiro@socionext.com 2018-06-27T03:13:48+00:00 8e75887d321d102200abf3a9fa621e2c10ff4cc5 What we want here is to embed a user-space program into the kernel. Instead of the complex ELF magic, let's simply wrap it in the assembly with the '.incbin' directive. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
What we want here is to embed a user-space program into the kernel.
Instead of the complex ELF magic, let's simply wrap it in the assembly
with the '.incbin' directive.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: check compiler capability in Kconfig 2018-06-28T04:36:39+00:00 Masahiro Yamada yamada.masahiro@socionext.com 2018-06-26T03:55:35+00:00 88e85a7daf8e21f2d6cb054374d480c540725cde With the brand-new syntax extension of Kconfig, we can directly check the compiler capability in the configuration phase. If the cc-can-link.sh fails, the BPFILTER_UMH is automatically hidden by the dependency. I also deleted 'default n', which is no-op. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
With the brand-new syntax extension of Kconfig, we can directly
check the compiler capability in the configuration phase.

If the cc-can-link.sh fails, the BPFILTER_UMH is automatically
hidden by the dependency.

I also deleted 'default n', which is no-op.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix user mode helper cross compilation 2018-06-21T00:19:19+00:00 Matteo Croce mcroce@redhat.com 2018-06-20T14:04:34+00:00 c24fb5e68ebfd485ecaa8b5d40cb4721a1d137ee Use $(OBJDUMP) instead of literal 'objdump' to avoid using host toolchain when cross compiling. Fixes: 421780fd4983 ("bpfilter: fix build error") Signed-off-by: Matteo Croce <mcroce@redhat.com> Reported-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Use $(OBJDUMP) instead of literal 'objdump' to avoid
using host toolchain when cross compiling.

Fixes: 421780fd4983 ("bpfilter: fix build error")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Reported-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: ignore binary files 2018-06-20T00:07:46+00:00 Matteo Croce mcroce@redhat.com 2018-06-19T15:21:36+00:00 8b26a06ad4f2a12425f1f63a0ee57f42961dfd1e net/bpfilter/bpfilter_umh is a binary file generated when bpfilter is enabled, add it to .gitignore to avoid committing it. Fixes: d2ba09c17a064 ("net: add skeleton of bpfilter kernel module") Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
net/bpfilter/bpfilter_umh is a binary file generated when bpfilter is
enabled, add it to .gitignore to avoid committing it.

Fixes: d2ba09c17a064 ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix build error 2018-06-20T00:07:46+00:00 Matteo Croce mcroce@redhat.com 2018-06-19T15:16:20+00:00 421780fd498399235b044638e85b352d6da20b6a bpfilter Makefile assumes that the system locale is en_US, and the parsing of objdump output fails. Set LC_ALL=C and, while at it, rewrite the objdump parsing so it spawns only 2 processes instead of 7. Fixes: d2ba09c17a064 ("net: add skeleton of bpfilter kernel module") Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
bpfilter Makefile assumes that the system locale is en_US, and the
parsing of objdump output fails.
Set LC_ALL=C and, while at it, rewrite the objdump parsing so it spawns
only 2 processes instead of 7.

Fixes: d2ba09c17a064 ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix race in pipe access 2018-06-08T00:07:28+00:00 Alexei Starovoitov ast@kernel.org 2018-06-07T22:31:14+00:00 66e58e0ef80a56a1d7857b6ce121141563cdd93e syzbot reported the following crash [ 338.293946] bpfilter: read fail -512 [ 338.304515] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 338.311863] general protection fault: 0000 [#1] SMP KASAN [ 338.344360] RIP: 0010:__vfs_write+0x4a6/0x960 [ 338.426363] Call Trace: [ 338.456967] __kernel_write+0x10c/0x380 [ 338.460928] __bpfilter_process_sockopt+0x1d8/0x35b [ 338.487103] bpfilter_mbox_request+0x4d/0xb0 [ 338.491492] bpfilter_ip_get_sockopt+0x6b/0x90 This can happen when multiple cpus trying to talk to user mode process via bpfilter_mbox_request(). One cpu grabs the mutex while another goes to sleep on the same mutex. Then former cpu sees that umh pipe is down and shuts down the pipes. Later cpu finally acquires the mutex and crashes on freed pipe. Fix the race by using info.pid as an indicator that umh and pipes are healthy and check it after acquiring the mutex. Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module") Reported-by: syzbot+7ade6c94abb2774c0fee@syzkaller.appspotmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
syzbot reported the following crash
[  338.293946] bpfilter: read fail -512
[  338.304515] kasan: GPF could be caused by NULL-ptr deref or user memory access
[  338.311863] general protection fault: 0000 [#1] SMP KASAN
[  338.344360] RIP: 0010:__vfs_write+0x4a6/0x960
[  338.426363] Call Trace:
[  338.456967]  __kernel_write+0x10c/0x380
[  338.460928]  __bpfilter_process_sockopt+0x1d8/0x35b
[  338.487103]  bpfilter_mbox_request+0x4d/0xb0
[  338.491492]  bpfilter_ip_get_sockopt+0x6b/0x90

This can happen when multiple cpus trying to talk to user mode process
via bpfilter_mbox_request(). One cpu grabs the mutex while another goes to
sleep on the same mutex. Then former cpu sees that umh pipe is down and
shuts down the pipes. Later cpu finally acquires the mutex and crashes
on freed pipe.
Fix the race by using info.pid as an indicator that umh and pipes are healthy
and check it after acquiring the mutex.

Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
Reported-by: syzbot+7ade6c94abb2774c0fee@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix OUTPUT_FORMAT 2018-06-07T20:56:48+00:00 Alexei Starovoitov ast@fb.com 2018-06-07T17:29:29+00:00 8d97ca6b6755bf7ef57d323642ca9ee80d689782 CONFIG_OUTPUT_FORMAT is x86 only macro. Used objdump to extract elf file format. Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module") Reported-by: David S. Miller <davem@davemloft.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
CONFIG_OUTPUT_FORMAT is x86 only macro.
Used objdump to extract elf file format.

Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: switch to CC from HOSTCC 2018-06-05T14:21:18+00:00 Alexei Starovoitov ast@kernel.org 2018-06-05T02:53:41+00:00 819dd92b9c0bc7bce9097d8c1f14240f471bb386 check that CC can build executables and use that compiler instead of HOSTCC Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
check that CC can build executables and use that compiler instead of HOSTCC

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix a build err 2018-05-29T19:20:21+00:00 YueHaibing yuehaibing@huawei.com 2018-05-25T10:17:57+00:00 ae40832e53c33fab2755571dabc1378117bc50d4 gcc-7.3.0 report following err: HOSTCC net/bpfilter/main.o In file included from net/bpfilter/main.c:9:0: ./include/uapi/linux/bpf.h:12:10: fatal error: linux/bpf_common.h: No such file or directory #include <linux/bpf_common.h> remove it by adding a include path. Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
gcc-7.3.0 report following err:

  HOSTCC  net/bpfilter/main.o
In file included from net/bpfilter/main.c:9:0:
./include/uapi/linux/bpf.h:12:10: fatal error: linux/bpf_common.h: No such file or directory
 #include <linux/bpf_common.h>

remove it by adding a include path.
Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bpfilter: fix building without CONFIG_INET 2018-05-29T12:13:35+00:00 Arnd Bergmann arnd@arndb.de 2018-05-29T09:55:06+00:00 d71dbdaa2d94d425fff4a59e10eb5be9f61a2661 bpfilter_process_sockopt is a callback that gets called from ip_setsockopt() and ip_getsockopt(). However, when CONFIG_INET is disabled, it never gets called at all, and assigning a function to the callback pointer results in a link failure: net/bpfilter/bpfilter_kern.o: In function `__stop_umh': bpfilter_kern.c:(.text.unlikely+0x3): undefined reference to `bpfilter_process_sockopt' net/bpfilter/bpfilter_kern.o: In function `load_umh': bpfilter_kern.c:(.init.text+0x73): undefined reference to `bpfilter_process_sockopt' Since there is no caller in this configuration, I assume we can simply make the assignment conditional. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net> 
bpfilter_process_sockopt is a callback that gets called from
ip_setsockopt() and ip_getsockopt(). However, when CONFIG_INET is
disabled, it never gets called at all, and assigning a function to the
callback pointer results in a link failure:

net/bpfilter/bpfilter_kern.o: In function `__stop_umh':
bpfilter_kern.c:(.text.unlikely+0x3): undefined reference to `bpfilter_process_sockopt'
net/bpfilter/bpfilter_kern.o: In function `load_umh':
bpfilter_kern.c:(.init.text+0x73): undefined reference to `bpfilter_process_sockopt'

Since there is no caller in this configuration, I assume we can
simply make the assignment conditional.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>