lkml.org 
[lkml]   [2019]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH bpf] samples/bpf: suppress compiler warning
From
Date
On 05/20/2019 11:49 PM, Matteo Croce wrote:
> GCC 9 fails to calculate the size of local constant strings and produces a
> false positive:
>
> samples/bpf/task_fd_query_user.c: In function ‘test_debug_fs_uprobe’:
> samples/bpf/task_fd_query_user.c:242:67: warning: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size 215 [-Wformat-truncation=]
> 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id",
> | ^~
> 243 | event_type, event_alias);
> | ~~~~~~~~~~~
> samples/bpf/task_fd_query_user.c:242:2: note: ‘snprintf’ output between 45 and 300 bytes into a destination of size 256
> 242 | snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id",
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 243 | event_type, event_alias);
> | ~~~~~~~~~~~~~~~~~~~~~~~~
>
> Workaround this by lowering the buffer size to a reasonable value.
> Related GCC Bugzilla: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83431
>
> Signed-off-by: Matteo Croce <mcroce@redhat.com>

Applied, thanks!

\
 
 \ /
  Last update: 2019-05-21 16:57    [W:0.319 / U:0.380 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site