diff options
| author | Lucy Mielke <lucymielke@icloud.com> | 2023-10-12 12:44:32 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-10-12 20:37:59 +0200 |
| commit | ac8b60be078abebc3ab8836f3f0ecac6980e0b4f (patch) | |
| tree | 5813336a949675ed3db3ddebc10e5c137bd1034f /kernel/locking | |
| parent | e6115c6f7a0ce3388cc60b69a284facf78b5dbfd (diff) | |
locking/lockdep: Fix string sizing bug that triggers a format-truncation compiler-warning
On an allyesconfig, with "treat warnings as errors" unset, GCC emits
these warnings:
kernel/locking/lockdep_proc.c:438:32: Warning: Format specifier '%lld' may
be truncated when writing 1 to 17 bytes into a region
of size 15 [-Wformat-truncation=]
kernel/locking/lockdep_proc.c:438:31: Note: Format directive argument is
in the range [-9223372036854775, 9223372036854775]
kernel/locking/lockdep_proc.c:438:9: Note: 'snprintf' has output
between 5 and 22 bytes into a target of size 15
In seq_time(), the longest s64 is "-9223372036854775808"-ish, which
converted to the fixed-point float format is "-9223372036854775.80": 21 bytes,
plus termination is another byte: 22. Therefore, a larger buffer size
of 22 is needed here - not 15. The code was safe due to the snprintf().
Fix it.
Signed-off-by: Lucy Mielke <lucymielke@icloud.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/ZSfOEHRkZAWaQr3U@fedora.fritz.box
Diffstat (limited to 'kernel/locking')
| -rw-r--r-- | kernel/locking/lockdep_proc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index 15fdc7fa5c68..e2bfb1db589d 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -440,7 +440,7 @@ static void snprint_time(char *buf, size_t bufsiz, s64 nr) static void seq_time(struct seq_file *m, s64 time) { - char num[15]; + char num[22]; snprint_time(num, sizeof(num), time); seq_printf(m, " %14s", num); |