| Message ID | 20220927070247.23148-1-yuzhe@nfschina.com |
|---|---|
| State | Accepted |
| Commit | df4f5aa75d87921d3467942165e3879269e06b33 |
| Headers | show |
| Series | cxl/pmem: Use size_add() against integer overflow | expand |
On Tue, Sep 27, 2022 at 12:02:47AM -0700, Yu Zhe wrote: > "struct_size() + n" may cause a integer overflow, > use size_add() to handle it. > > Signed-off-by: Yu Zhe <yuzhe@nfschina.com> > --- > drivers/cxl/pmem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c > index 7dc0a2fa1a6b..8c08aa009a56 100644 > --- a/drivers/cxl/pmem.c > +++ b/drivers/cxl/pmem.c > @@ -148,7 +148,7 @@ static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds, > return -EINVAL; > > /* 4-byte status follows the input data in the payload */ > - if (struct_size(cmd, in_buf, cmd->in_length) + 4 > buf_len) > + if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len) I don't see any benefit here. struct_size() calls __ab_c_size() which already calls check_add_overflow()? So why wrap that in another check? Were you able to get this to fail with some user input? Ira > return -EINVAL; > > set_lsa = > -- > 2.11.0 >
在 2022年09月28日 00:23, Ira Weiny 写道: > On Tue, Sep 27, 2022 at 12:02:47AM -0700, Yu Zhe wrote: >> "struct_size() + n" may cause a integer overflow, >> use size_add() to handle it. >> >> Signed-off-by: Yu Zhe <yuzhe@nfschina.com> >> --- >> drivers/cxl/pmem.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c >> index 7dc0a2fa1a6b..8c08aa009a56 100644 >> --- a/drivers/cxl/pmem.c >> +++ b/drivers/cxl/pmem.c >> @@ -148,7 +148,7 @@ static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds, >> return -EINVAL; >> >> /* 4-byte status follows the input data in the payload */ >> - if (struct_size(cmd, in_buf, cmd->in_length) + 4 > buf_len) >> + if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len) > I don't see any benefit here. > > struct_size() calls __ab_c_size() which already calls check_add_overflow()? So > why wrap that in another check? "struct_size() + 4" still might cause overflow, so there need to use "size_add" to check it. > Were you able to get this to fail with some user input? > > Ira > >> return -EINVAL; >> >> set_lsa = >> -- >> 2.11.0 >> >>
Yu Zhe wrote: > "struct_size() + n" may cause a integer overflow, > use size_add() to handle it. > > Signed-off-by: Yu Zhe <yuzhe@nfschina.com> > --- > drivers/cxl/pmem.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c > index 7dc0a2fa1a6b..8c08aa009a56 100644 > --- a/drivers/cxl/pmem.c > +++ b/drivers/cxl/pmem.c > @@ -148,7 +148,7 @@ static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds, > return -EINVAL; > > /* 4-byte status follows the input data in the payload */ > - if (struct_size(cmd, in_buf, cmd->in_length) + 4 > buf_len) > + if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len) > return -EINVAL; Looks good, applied for v6.1-rc fixes.
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c index 7dc0a2fa1a6b..8c08aa009a56 100644 --- a/drivers/cxl/pmem.c +++ b/drivers/cxl/pmem.c @@ -148,7 +148,7 @@ static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds, return -EINVAL; /* 4-byte status follows the input data in the payload */ - if (struct_size(cmd, in_buf, cmd->in_length) + 4 > buf_len) + if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len) return -EINVAL; set_lsa =
"struct_size() + n" may cause a integer overflow, use size_add() to handle it. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> --- drivers/cxl/pmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)