| Message ID | 20191211080109.18765-1-andrey.zhizhikin@leica-geosystems.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
| Series | tools lib api fs: fix gcc9 compilation error | expand |
Hello all, I'd like to have a gentle ping on this patch, if someone could review and apply it - I'd really appreciate it. On Wed, Dec 11, 2019 at 9:01 AM Andrey Zhizhikin <andrey.z@gmail.com> wrote: > > GCC9 introduced string hardening mechanisms, which exhibits the error > during fs api compilation: > > error: '__builtin_strncpy' specified bound 4096 equals destination size > [-Werror=stringop-truncation] > > This comes when the length of copy passed to strncpy is is equal to > destination size, which could potentially lead to buffer overflow. > > There is a need to mitigate this potential issue by limiting the size of > destination by 1 and explicitly terminate the destination with NULL. > > Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Jiri Olsa <jolsa@kernel.org> > --- > tools/lib/api/fs/fs.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c > index 11b3885e833e..027b18f7ed8c 100644 > --- a/tools/lib/api/fs/fs.c > +++ b/tools/lib/api/fs/fs.c > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > size_t name_len = strlen(fs->name); > /* name + "_PATH" + '\0' */ > char upper_name[name_len + 5 + 1]; > + > memcpy(upper_name, fs->name, name_len); > mem_toupper(upper_name, name_len); > strcpy(&upper_name[name_len], "_PATH"); > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > return false; > > fs->found = true; > - strncpy(fs->path, override_path, sizeof(fs->path)); > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > + fs->path[sizeof(fs->path) - 1] = '\0'; > return true; > } > > -- > 2.17.1 >
On (19/12/11 08:01), Andrey Zhizhikin wrote: [..] > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > size_t name_len = strlen(fs->name); > /* name + "_PATH" + '\0' */ > char upper_name[name_len + 5 + 1]; > + > memcpy(upper_name, fs->name, name_len); > mem_toupper(upper_name, name_len); > strcpy(&upper_name[name_len], "_PATH"); > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > return false; > > fs->found = true; > - strncpy(fs->path, override_path, sizeof(fs->path)); > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > + fs->path[sizeof(fs->path) - 1] = '\0'; I think the trend these days is to prefer stracpy/strscpy over strcpy/strlcpy/strncpy. -ss
On (19/12/18 12:10), Sergey Senozhatsky wrote: > On (19/12/11 08:01), Andrey Zhizhikin wrote: > [..] > > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > > size_t name_len = strlen(fs->name); > > /* name + "_PATH" + '\0' */ > > char upper_name[name_len + 5 + 1]; > > + > > memcpy(upper_name, fs->name, name_len); > > mem_toupper(upper_name, name_len); > > strcpy(&upper_name[name_len], "_PATH"); > > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > > return false; > > > > fs->found = true; > > - strncpy(fs->path, override_path, sizeof(fs->path)); > > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > > + fs->path[sizeof(fs->path) - 1] = '\0'; > > I think the trend these days is to prefer stracpy/strscpy over > strcpy/strlcpy/strncpy. Scratch that. This is user-space, I should pay more attention. -ss
On Wed, Dec 11, 2019 at 08:01:09AM +0000, Andrey Zhizhikin wrote: > GCC9 introduced string hardening mechanisms, which exhibits the error > during fs api compilation: > > error: '__builtin_strncpy' specified bound 4096 equals destination size > [-Werror=stringop-truncation] > > This comes when the length of copy passed to strncpy is is equal to > destination size, which could potentially lead to buffer overflow. > > There is a need to mitigate this potential issue by limiting the size of > destination by 1 and explicitly terminate the destination with NULL. > > Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Jiri Olsa <jolsa@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> thanks, jirka > --- > tools/lib/api/fs/fs.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c > index 11b3885e833e..027b18f7ed8c 100644 > --- a/tools/lib/api/fs/fs.c > +++ b/tools/lib/api/fs/fs.c > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > size_t name_len = strlen(fs->name); > /* name + "_PATH" + '\0' */ > char upper_name[name_len + 5 + 1]; > + > memcpy(upper_name, fs->name, name_len); > mem_toupper(upper_name, name_len); > strcpy(&upper_name[name_len], "_PATH"); > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > return false; > > fs->found = true; > - strncpy(fs->path, override_path, sizeof(fs->path)); > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > + fs->path[sizeof(fs->path) - 1] = '\0'; > return true; > } > > -- > 2.17.1 >
On Wed 2019-12-11 08:01:09, Andrey Zhizhikin wrote: > GCC9 introduced string hardening mechanisms, which exhibits the error > during fs api compilation: > > error: '__builtin_strncpy' specified bound 4096 equals destination size > [-Werror=stringop-truncation] > > This comes when the length of copy passed to strncpy is is equal to > destination size, which could potentially lead to buffer overflow. > > There is a need to mitigate this potential issue by limiting the size of > destination by 1 and explicitly terminate the destination with NULL. > > Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Best Regards, Petr
Em Wed, Dec 11, 2019 at 08:01:09AM +0000, Andrey Zhizhikin escreveu: > GCC9 introduced string hardening mechanisms, which exhibits the error > during fs api compilation: > > error: '__builtin_strncpy' specified bound 4096 equals destination size > [-Werror=stringop-truncation] > > This comes when the length of copy passed to strncpy is is equal to > destination size, which could potentially lead to buffer overflow. > > There is a need to mitigate this potential issue by limiting the size of > destination by 1 and explicitly terminate the destination with NULL. Thanks, applied and collected the reviewed-by and acked-by provided, - Arnaldo > Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Cc: Jiri Olsa <jolsa@kernel.org> > --- > tools/lib/api/fs/fs.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c > index 11b3885e833e..027b18f7ed8c 100644 > --- a/tools/lib/api/fs/fs.c > +++ b/tools/lib/api/fs/fs.c > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > size_t name_len = strlen(fs->name); > /* name + "_PATH" + '\0' */ > char upper_name[name_len + 5 + 1]; > + > memcpy(upper_name, fs->name, name_len); > mem_toupper(upper_name, name_len); > strcpy(&upper_name[name_len], "_PATH"); > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > return false; > > fs->found = true; > - strncpy(fs->path, override_path, sizeof(fs->path)); > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > + fs->path[sizeof(fs->path) - 1] = '\0'; > return true; > } > > -- > 2.17.1
On Wed, Dec 18, 2019 at 3:33 PM Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> wrote: > > Em Wed, Dec 11, 2019 at 08:01:09AM +0000, Andrey Zhizhikin escreveu: > > GCC9 introduced string hardening mechanisms, which exhibits the error > > during fs api compilation: > > > > error: '__builtin_strncpy' specified bound 4096 equals destination size > > [-Werror=stringop-truncation] > > > > This comes when the length of copy passed to strncpy is is equal to > > destination size, which could potentially lead to buffer overflow. > > > > There is a need to mitigate this potential issue by limiting the size of > > destination by 1 and explicitly terminate the destination with NULL. > > Thanks, applied and collected the reviewed-by and acked-by provided, Thanks a lot for review and collecting this patch! > > - Arnaldo > > > Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> > > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > > Cc: Jiri Olsa <jolsa@kernel.org> > > --- > > tools/lib/api/fs/fs.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c > > index 11b3885e833e..027b18f7ed8c 100644 > > --- a/tools/lib/api/fs/fs.c > > +++ b/tools/lib/api/fs/fs.c > > @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) > > size_t name_len = strlen(fs->name); > > /* name + "_PATH" + '\0' */ > > char upper_name[name_len + 5 + 1]; > > + > > memcpy(upper_name, fs->name, name_len); > > mem_toupper(upper_name, name_len); > > strcpy(&upper_name[name_len], "_PATH"); > > @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) > > return false; > > > > fs->found = true; > > - strncpy(fs->path, override_path, sizeof(fs->path)); > > + strncpy(fs->path, override_path, sizeof(fs->path) - 1); > > + fs->path[sizeof(fs->path) - 1] = '\0'; > > return true; > > } > > > > -- > > 2.17.1 > > -- > > - Arnaldo
diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c index 11b3885e833e..027b18f7ed8c 100644 --- a/tools/lib/api/fs/fs.c +++ b/tools/lib/api/fs/fs.c @@ -210,6 +210,7 @@ static bool fs__env_override(struct fs *fs) size_t name_len = strlen(fs->name); /* name + "_PATH" + '\0' */ char upper_name[name_len + 5 + 1]; + memcpy(upper_name, fs->name, name_len); mem_toupper(upper_name, name_len); strcpy(&upper_name[name_len], "_PATH"); @@ -219,7 +220,8 @@ static bool fs__env_override(struct fs *fs) return false; fs->found = true; - strncpy(fs->path, override_path, sizeof(fs->path)); + strncpy(fs->path, override_path, sizeof(fs->path) - 1); + fs->path[sizeof(fs->path) - 1] = '\0'; return true; }
GCC9 introduced string hardening mechanisms, which exhibits the error during fs api compilation: error: '__builtin_strncpy' specified bound 4096 equals destination size [-Werror=stringop-truncation] This comes when the length of copy passed to strncpy is is equal to destination size, which could potentially lead to buffer overflow. There is a need to mitigate this potential issue by limiting the size of destination by 1 and explicitly terminate the destination with NULL. Signed-off-by: Andrey Zhizhikin <andrey.zhizhikin@leica-geosystems.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> --- tools/lib/api/fs/fs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)