| Message ID | 20210616042534.315097-1-wanghai38@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 7c6090ee2a7b3315410cfc83a94c3eb057407b25 |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf] samples/bpf: Fix the error return code of xdp_redirect's main() | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 13 of 13 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 6 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
Hello: This patch was applied to bpf/bpf-next.git (refs/heads/master): On Wed, 16 Jun 2021 12:25:34 +0800 you wrote: > Fix to return a negative error code from the error handling > case instead of 0, as done elsewhere in this function. > > If bpf_map_update_elem() failed, main() should return a negative error. > > Fixes: 832622e6bd18 ("xdp: sample program for new bpf_redirect helper") > Signed-off-by: Wang Hai <wanghai38@huawei.com> > > [...] Here is the summary with links: - [bpf] samples/bpf: Fix the error return code of xdp_redirect's main() https://git.kernel.org/bpf/bpf-next/c/7c6090ee2a7b You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
On 16/06/2021 06.25, Wang Hai wrote: > Fix to return a negative error code from the error handling > case instead of 0, as done elsewhere in this function. The main() function in C should never return a negative value on Unix POSIX systems. There is a good explaination in exit(3p): `man 3p exit` The value of status may be 0, EXIT_SUCCESS, EXIT_FAILURE, or any other value, though only the least significant 8 bits (that is, status & 0377) shall be available to a waiting parent process. Thus, negative values are often seen as 255 in the $? program exit status variable $?. Also explained in exit(3): The C standard specifies two constants, EXIT_SUCCESS=0 and EXIT_FAILURE=1. I see the 'samples/bpf/xdp_redirect_user.c' in most places just use 0 or 1. > If bpf_map_update_elem() failed, main() should return a negative error. > > Fixes: 832622e6bd18 ("xdp: sample program for new bpf_redirect helper") > Signed-off-by: Wang Hai <wanghai38@huawei.com> > --- > samples/bpf/xdp_redirect_user.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c > index 41d705c3a1f7..c903f1ccc15e 100644 > --- a/samples/bpf/xdp_redirect_user.c > +++ b/samples/bpf/xdp_redirect_user.c > @@ -213,5 +213,5 @@ int main(int argc, char **argv) > poll_stats(2, ifindex_out); > > out: > - return 0; > + return ret; > } (Sorry, I didn't complain it time as I see this patch is already applied)
在 2021/7/2 18:29, Jesper Dangaard Brouer 写道: > > On 16/06/2021 06.25, Wang Hai wrote: >> Fix to return a negative error code from the error handling >> case instead of 0, as done elsewhere in this function. > > The main() function in C should never return a negative value on Unix > POSIX systems. > > > There is a good explaination in exit(3p): `man 3p exit` > > The value of status may be 0, EXIT_SUCCESS, EXIT_FAILURE, or any > other value, though only the least significant 8 bits (that is, status > & 0377) shall be available to a waiting parent process. > > Thus, negative values are often seen as 255 in the $? program exit > status variable $?. > > > Also explained in exit(3): > > The C standard specifies two constants, EXIT_SUCCESS=0 and > EXIT_FAILURE=1. > > I see the 'samples/bpf/xdp_redirect_user.c' in most places just use 0 > or 1. > Got it, thanks for the explanation, I will fix it to return 1, just like the other error paths in samples/bpf/xdp_redirect_user.c > >> If bpf_map_update_elem() failed, main() should return a negative error. >> >> Fixes: 832622e6bd18 ("xdp: sample program for new bpf_redirect helper") >> Signed-off-by: Wang Hai <wanghai38@huawei.com> >> --- >> samples/bpf/xdp_redirect_user.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/samples/bpf/xdp_redirect_user.c >> b/samples/bpf/xdp_redirect_user.c >> index 41d705c3a1f7..c903f1ccc15e 100644 >> --- a/samples/bpf/xdp_redirect_user.c >> +++ b/samples/bpf/xdp_redirect_user.c >> @@ -213,5 +213,5 @@ int main(int argc, char **argv) >> poll_stats(2, ifindex_out); >> out: >> - return 0; >> + return ret; >> } > > > (Sorry, I didn't complain it time as I see this patch is already applied) > > . >
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c index 41d705c3a1f7..c903f1ccc15e 100644 --- a/samples/bpf/xdp_redirect_user.c +++ b/samples/bpf/xdp_redirect_user.c @@ -213,5 +213,5 @@ int main(int argc, char **argv) poll_stats(2, ifindex_out); out: - return 0; + return ret; }
Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. If bpf_map_update_elem() failed, main() should return a negative error. Fixes: 832622e6bd18 ("xdp: sample program for new bpf_redirect helper") Signed-off-by: Wang Hai <wanghai38@huawei.com> --- samples/bpf/xdp_redirect_user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)