| Message ID | 20181020172325.7450-1-peron.clem@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mmc-utils: fix overlapping with strncpy | expand |
+Chris On 20 October 2018 at 19:23, Clément Péron <peron.clem@gmail.com> wrote: > GCC 8.2 warns about an overlapping using strncpy. > > Replace strncpy with a memmove to avoid this issue. > > In file included from /usr/include/string.h:494, > from lsmmc.c:46: > In function ‘strncpy’, > inlined from ‘read_file’ at lsmmc.c:356:3: > /usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ accessing 4096 bytes at offsets 0 and 1 overlaps 4095 bytes at offset 1 [-Werror=restrict] > return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest)); > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > cc1: all warnings being treated as errors > make: *** [Makefile:36: lsmmc.o] Error 1 > > Signed-off-by: Clément Péron <peron.clem@gmail.com> You need post this to Chris Ball, as he maintains mmc-utils. Kind regards Uffe > --- > lsmmc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lsmmc.c b/lsmmc.c > index c4faa00..bcb854d 100644 > --- a/lsmmc.c > +++ b/lsmmc.c > @@ -353,7 +353,7 @@ char *read_file(char *name) > line[strlen(line) - 1] = '\0'; > > while (isspace(line[0])) > - strncpy(&line[0], &line[1], sizeof(line)); > + memmove(&line[0], &line[1], sizeof(line)-1); > > return strdup(line); > } > -- > 2.19.1 >
diff --git a/lsmmc.c b/lsmmc.c index c4faa00..bcb854d 100644 --- a/lsmmc.c +++ b/lsmmc.c @@ -353,7 +353,7 @@ char *read_file(char *name) line[strlen(line) - 1] = '\0'; while (isspace(line[0])) - strncpy(&line[0], &line[1], sizeof(line)); + memmove(&line[0], &line[1], sizeof(line)-1); return strdup(line); }
GCC 8.2 warns about an overlapping using strncpy. Replace strncpy with a memmove to avoid this issue. In file included from /usr/include/string.h:494, from lsmmc.c:46: In function ‘strncpy’, inlined from ‘read_file’ at lsmmc.c:356:3: /usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: error: ‘__builtin_strncpy’ accessing 4096 bytes at offsets 0 and 1 overlaps 4095 bytes at offset 1 [-Werror=restrict] return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors make: *** [Makefile:36: lsmmc.o] Error 1 Signed-off-by: Clément Péron <peron.clem@gmail.com> --- lsmmc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)