linux/tools/lib
Ian Rogers 7a078d2d18 libbpf, hashmap: Fix undefined behavior in hash_bits
If bits is 0, the case when the map is empty, then the >> is the size of
the register which is undefined behavior - on x86 it is the same as a
shift by 0.

Fix by handling the 0 case explicitly and guarding calls to hash_bits for
empty maps in hashmap__for_each_key_entry and hashmap__for_each_entry_safe.

Fixes: e3b9242240 ("libbpf: add resizable non-thread safe internal hashmap")
Suggested-by: Andrii Nakryiko <andriin@fb.com>,
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201029223707.494059-1-irogers@google.com
2020-11-02 23:33:51 +01:00
..
api libperf: Avoid counting of nonfilterable fdarray fds 2020-07-21 09:53:22 -03:00
bpf libbpf, hashmap: Fix undefined behavior in hash_bits 2020-11-02 23:33:51 +01:00
lockdep .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
perf perf tools: Add size to 'struct perf_record_header_build_id' 2020-10-14 11:28:12 -03:00
subcmd tools: Avoid comma separated statements 2020-10-02 10:36:36 -06:00
symbol libsymbols kallsyms: Move hex2u64 out of header 2020-05-05 16:35:32 -03:00
traceevent tools lib traceevent: Hide non API functions 2020-10-13 11:47:38 -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 tools bitmap: Implement bitmap_equal() operation at bitmap API 2020-01-06 11:46:04 -03:00
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 tools/: replace HTTP links with HTTPS ones 2020-08-07 11:33:21 -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: Fix builds when glibc contains strlcpy() 2020-01-06 11:46:10 -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