Tunable definitions with more than one '=' on are parsed and enabled,
and any subsequent '=' are ignored. It means that tunables in the form
'tunable=tunable=value' or 'tunable=value=value' are handled as
'tunable=value'. These inputs are likely user input errors, which
should not be accepted.
Checked on x86_64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
---
elf/dl-tunables.c | 6 ++++--
elf/tst-tunables.c | 22 +++++++++++++++++-----
2 files changed, 21 insertions(+), 7 deletions(-)
@@ -192,10 +192,12 @@ parse_tunables (char *valstring)
const char *value = p;
- while (*p != ':' && *p != '\0')
+ while (*p != '=' && *p != ':' && *p != '\0')
p++;
- if (*p == '\0')
+ if (*p == '=')
+ break;
+ else if (*p == '\0')
done = true;
else
*p++ = '\0';
@@ -161,24 +161,36 @@ static const struct test_t
0,
0,
},
- /* The ill-formatted tunable is also skipped. */
+ /* If there is a ill-formatted key=value, everything after is also ignored. */
{
"glibc.malloc.mmap_threshold=glibc.malloc.mmap_threshold=4096:glibc.malloc.check=2",
- 2,
+ 0,
0,
0,
},
- /* For an integer tunable, parse will stop on non number character. */
{
"glibc.malloc.check=2=2",
- 2,
+ 0,
0,
0,
},
{
"glibc.malloc.check=2=2:glibc.malloc.mmap_threshold=4096",
+ 0,
+ 0,
+ 0,
+ },
+ {
+ "glibc.malloc.check=2=2:glibc.malloc.check=2",
+ 0,
+ 0,
+ 0,
+ },
+ /* Valid tunables set before ill-formatted ones are set. */
+ {
+ "glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096=4096",
2,
- 4096,
+ 0,
0,
}
};