On Mon, Aug 8, 2022 at 10:18 AM Yonghong Song <yhs@xxxxxx> wrote: > > > > On 8/6/22 3:20 AM, Hengqi Chen wrote: > > Currently, resolve_full_path() requires executable permission for both > > programs and shared libraries. This causes failures on distos like Debian > > since the shared libraries are not installed executable ([0]). Let's remove > > executable permission check for shared libraries. > > > > [0]: https://www.debian.org/doc/debian-policy/ > > The document is too big. Could you be more specific about > which chapter and copy-paste related statements in the commit message? > I just dropped that link and added "and Linux is not requiring shared libraries to have executable permissions". Pushed to bpf-next, thanks. > > > > Reported-by: Goro Fuji <goro@xxxxxxxxxx> > > Signed-off-by: Hengqi Chen <hengqi.chen@xxxxxxxxx> > > --- > > tools/lib/bpf/libbpf.c | 7 ++++--- > > 1 file changed, 4 insertions(+), 3 deletions(-) > > > > diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c > > index 77e3797cf75a..f0ce7423afb8 100644 > > --- a/tools/lib/bpf/libbpf.c > > +++ b/tools/lib/bpf/libbpf.c > > @@ -10666,7 +10666,7 @@ static const char *arch_specific_lib_paths(void) > > static int resolve_full_path(const char *file, char *result, size_t result_sz) > > { > > const char *search_paths[3] = {}; > > - int i; > > + int i, perm = R_OK; > > > > if (str_has_sfx(file, ".so") || strstr(file, ".so.")) { > > search_paths[0] = getenv("LD_LIBRARY_PATH"); > > @@ -10675,6 +10675,7 @@ static int resolve_full_path(const char *file, char *result, size_t result_sz) > > } else { > > search_paths[0] = getenv("PATH"); > > search_paths[1] = "/usr/bin:/usr/sbin"; > > + perm |= X_OK; I changed this bit a bit to just set perm = R_OK for library case and explicitly perm = R_OK | X_OK for executable case. I think that makes it a bit easier to follow (and it doesn't change the outcome). Thanks for the quick follow up from Github issue! > > } > > > > for (i = 0; i < ARRAY_SIZE(search_paths); i++) { > > @@ -10693,8 +10694,8 @@ static int resolve_full_path(const char *file, char *result, size_t result_sz) > > if (!seg_len) > > continue; > > snprintf(result, result_sz, "%.*s/%s", seg_len, s, file); > > - /* ensure it is an executable file/link */ > > - if (access(result, R_OK | X_OK) < 0) > > + /* ensure it has required permissions */ > > + if (access(result, perm) < 0) > > continue; > > pr_debug("resolved '%s' to '%s'\n", file, result); > > return 0;
