| Message ID | 20250216022523.647342-1-ant.v.moryakov@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | David Ahern |
| Headers | show |
| Series | ip: handle NULL return from localtime in strxf_time in | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Sun, 16 Feb 2025 05:25:23 +0300 Anton Moryakov <ant.v.moryakov@gmail.com> wrote: > Static analyzer reported: > Pointer 'tp', returned from function 'localtime' at ipxfrm.c:352, may be NULL > and is dereferenced at ipxfrm.c:354 by calling function 'strftime'. > > Corrections explained: > The function localtime() may return NULL if the provided time value is > invalid. This commit adds a check for NULL and handles the error case > by copying "invalid-time" into the output buffer. > Unlikely, but may return an error > > Triggers found by static analyzer Svace. > > Signed-off-by: Anton Moryakov <ant.v.moryakov@gmail.com> Seems like you are creating dead code. Unless glibc is broken this can never happen.
diff --git a/ip/ipxfrm.c b/ip/ipxfrm.c index 90d25aac..9bfd96ab 100644 --- a/ip/ipxfrm.c +++ b/ip/ipxfrm.c @@ -351,7 +351,12 @@ static const char *strxf_time(__u64 time) t = (long)time; tp = localtime(&t); - strftime(str, sizeof(str), "%Y-%m-%d %T", tp); + if (!tp) { + /* Handle error case */ + strcpy(str, "invalid-time"); + } else { + strftime(str, sizeof(str), "%Y-%m-%d %T", tp); + } } return str;
Static analyzer reported: Pointer 'tp', returned from function 'localtime' at ipxfrm.c:352, may be NULL and is dereferenced at ipxfrm.c:354 by calling function 'strftime'. Corrections explained: The function localtime() may return NULL if the provided time value is invalid. This commit adds a check for NULL and handles the error case by copying "invalid-time" into the output buffer. Unlikely, but may return an error Triggers found by static analyzer Svace. Signed-off-by: Anton Moryakov <ant.v.moryakov@gmail.com> --- ip/ipxfrm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)