2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-26 23:55:40 +08:00
linux-next/tools/lib
Andrii Nakryiko d7a252708d libbpf: Improve handling of failed CO-RE relocations
Previously, if libbpf failed to resolve CO-RE relocation for some
instructions, it would either return error immediately, or, if
.relaxed_core_relocs option was set, would replace relocatable offset/imm part
of an instruction with a bogus value (-1). Neither approach is good, because
there are many possible scenarios where relocation is expected to fail (e.g.,
when some field knowingly can be missing on specific kernel versions). On the
other hand, replacing offset with invalid one can hide programmer errors, if
this relocation failue wasn't anticipated.

This patch deprecates .relaxed_core_relocs option and changes the approach to
always replacing instruction, for which relocation failed, with invalid BPF
helper call instruction. For cases where this is expected, BPF program should
already ensure that that instruction is unreachable, in which case this
invalid instruction is going to be silently ignored. But if instruction wasn't
guarded, BPF program will be rejected at verification step with verifier log
pointing precisely to the place in assembly where the problem is.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200124053837.2434679-1-andriin@fb.com
2020-01-24 22:16:26 +01:00
..
api tools lib api: Renaming pr_warning to pr_warn 2019-10-18 15:02:57 +02:00
bpf libbpf: Improve handling of failed CO-RE relocations 2020-01-24 22:16:26 +01:00
lockdep locking/lockdep: Remove unused @nested argument from lock_release() 2019-10-09 12:46:10 +02:00
subcmd libsubcmd: Use -O0 with DEBUG=1 2019-11-06 15:49:39 -03:00
symbol tools perf: Move from sane_ctype.h obtained from git to the Linux's original 2019-06-25 21:02:47 -03:00
traceevent tools lib traceevent: Fix memory leakage in filter_event 2019-12-20 18:47:50 -03:00
argv_split.c tools lib: Move argv_{split,free} from tools/perf/util/ 2019-07-01 22:50:40 -03:00
bitmap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230 2019-06-19 17:09:06 +02:00
ctype.c tools perf: Move from sane_ctype.h obtained from git to the Linux's original 2019-06-25 21:02:47 -03:00
find_bit.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
hweight.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rbtree.c rbtree: avoid generating code twice for the cached versions (tools copy) 2019-09-25 17:51:39 -07:00
str_error_r.c objtool, perf: Fix GCC 8 -Wrestrict error 2018-03-19 13:51:54 -03:00
string.c tools lib: Adopt strreplace() from the kernel 2019-07-01 22:50:40 -03:00
vsprintf.c perf script: Pad DSO name for --call-trace 2019-05-28 18:37:44 -03:00
zalloc.c tools lib: Adopt zalloc()/zfree() from tools/perf 2019-07-09 10:13:26 -03:00