diff options
| author | Zheng Yejian <[email protected]> | 2021-05-15 22:06:31 +0800 |
|---|---|---|
| committer | Andrew Morton <[email protected]> | 2022-11-30 16:13:18 -0800 |
| commit | c5f31c655bcc01b6da53b836ac951c1556245305 (patch) | |
| tree | b8bf5588b37bda48fff034aa91653d7df092d207 | |
| parent | 457139f16ae15d86df1e491fc45a9ea56def57b5 (diff) | |
acct: fix potential integer overflow in encode_comp_t()
The integer overflow is descripted with following codes:
> 317 static comp_t encode_comp_t(u64 value)
> 318 {
> 319 int exp, rnd;
......
> 341 exp <<= MANTSIZE;
> 342 exp += value;
> 343 return exp;
> 344 }
Currently comp_t is defined as type of '__u16', but the variable 'exp' is
type of 'int', so overflow would happen when variable 'exp' in line 343 is
greater than 65535.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Zheng Yejian <[email protected]>
Cc: Hanjun Guo <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Zhang Jinhao <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
| -rw-r--r-- | kernel/acct.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/acct.c b/kernel/acct.c index 31b09cf7189c..010667ce6080 100644 --- a/kernel/acct.c +++ b/kernel/acct.c @@ -350,6 +350,8 @@ static comp_t encode_comp_t(u64 value) exp++; } + if (exp > (((comp_t) ~0U) >> MANTSIZE)) + return (comp_t) ~0U; /* * Clean it up and polish it off. */ |