| Message ID | 20250410103442.17746-1-purvayeshi550@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] char: tpm: tpm-buf: Add sanity check fallback in read helpers | expand |
On Thu, Apr 10, 2025 at 04:04:42PM +0530, Purva Yeshi wrote: > Fix Smatch-detected issue: > > drivers/char/tpm/tpm-buf.c:208 tpm_buf_read_u8() error: > uninitialized symbol 'value'. > drivers/char/tpm/tpm-buf.c:225 tpm_buf_read_u16() error: > uninitialized symbol 'value'. > drivers/char/tpm/tpm-buf.c:242 tpm_buf_read_u32() error: > uninitialized symbol 'value'. > > Zero-initialize the return values in tpm_buf_read_u8(), > tpm_buf_read_u16(), and tpm_buf_read_u32() to guard against > uninitialized data in case of a boundary overflow. > > Add defensive initialization ensures the return values are > always defined, preventing undefined behavior if the unexpected > happens. > > Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> > --- > V1 - https://lore.kernel.org/all/20250409205536.210202-1-purvayeshi550@gmail.com/ > V2 - Update commit message to clarify patch adds a sanity check > > drivers/char/tpm/tpm-buf.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c > index e49a19fea3bd..dc882fc9fa9e 100644 > --- a/drivers/char/tpm/tpm-buf.c > +++ b/drivers/char/tpm/tpm-buf.c > @@ -201,7 +201,7 @@ static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void > */ > u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset) > { > - u8 value; > + u8 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > > @@ -218,7 +218,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u8); > */ > u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset) > { > - u16 value; > + u16 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > > @@ -235,7 +235,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u16); > */ > u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset) > { > - u32 value; > + u32 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > > -- > 2.34.1 > > It's good and I think this change is appropriate overall! Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> BR, Jarkko
On 10/04/25 18:07, Jarkko Sakkinen wrote: > On Thu, Apr 10, 2025 at 04:04:42PM +0530, Purva Yeshi wrote: >> Fix Smatch-detected issue: >> >> drivers/char/tpm/tpm-buf.c:208 tpm_buf_read_u8() error: >> uninitialized symbol 'value'. >> drivers/char/tpm/tpm-buf.c:225 tpm_buf_read_u16() error: >> uninitialized symbol 'value'. >> drivers/char/tpm/tpm-buf.c:242 tpm_buf_read_u32() error: >> uninitialized symbol 'value'. >> >> Zero-initialize the return values in tpm_buf_read_u8(), >> tpm_buf_read_u16(), and tpm_buf_read_u32() to guard against >> uninitialized data in case of a boundary overflow. >> >> Add defensive initialization ensures the return values are >> always defined, preventing undefined behavior if the unexpected >> happens. >> >> Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> >> --- >> V1 - https://lore.kernel.org/all/20250409205536.210202-1-purvayeshi550@gmail.com/ >> V2 - Update commit message to clarify patch adds a sanity check >> >> drivers/char/tpm/tpm-buf.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c >> index e49a19fea3bd..dc882fc9fa9e 100644 >> --- a/drivers/char/tpm/tpm-buf.c >> +++ b/drivers/char/tpm/tpm-buf.c >> @@ -201,7 +201,7 @@ static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void >> */ >> u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset) >> { >> - u8 value; >> + u8 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> @@ -218,7 +218,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u8); >> */ >> u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset) >> { >> - u16 value; >> + u16 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> @@ -235,7 +235,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u16); >> */ >> u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset) >> { >> - u32 value; >> + u32 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> -- >> 2.34.1 >> >> > > It's good and I think this change is appropriate overall! > > Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> > > BR, Jarkko Thank you for the review. Best Regards, Purva Yeshi
On Thu, Apr 10, 2025 at 04:04:42PM +0530, Purva Yeshi wrote: >Fix Smatch-detected issue: > >drivers/char/tpm/tpm-buf.c:208 tpm_buf_read_u8() error: >uninitialized symbol 'value'. >drivers/char/tpm/tpm-buf.c:225 tpm_buf_read_u16() error: >uninitialized symbol 'value'. >drivers/char/tpm/tpm-buf.c:242 tpm_buf_read_u32() error: >uninitialized symbol 'value'. > >Zero-initialize the return values in tpm_buf_read_u8(), >tpm_buf_read_u16(), and tpm_buf_read_u32() to guard against >uninitialized data in case of a boundary overflow. > >Add defensive initialization ensures the return values are >always defined, preventing undefined behavior if the unexpected >happens. > >Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> >--- >V1 - https://lore.kernel.org/all/20250409205536.210202-1-purvayeshi550@gmail.com/ >V2 - Update commit message to clarify patch adds a sanity check LGTM! Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> > > drivers/char/tpm/tpm-buf.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > >diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c >index e49a19fea3bd..dc882fc9fa9e 100644 >--- a/drivers/char/tpm/tpm-buf.c >+++ b/drivers/char/tpm/tpm-buf.c >@@ -201,7 +201,7 @@ static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void > */ > u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset) > { >- u8 value; >+ u8 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > >@@ -218,7 +218,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u8); > */ > u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset) > { >- u16 value; >+ u16 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > >@@ -235,7 +235,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u16); > */ > u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset) > { >- u32 value; >+ u32 value = 0; > > tpm_buf_read(buf, offset, sizeof(value), &value); > >-- >2.34.1 > >
On 11/04/25 12:50, Stefano Garzarella wrote: > On Thu, Apr 10, 2025 at 04:04:42PM +0530, Purva Yeshi wrote: >> Fix Smatch-detected issue: >> >> drivers/char/tpm/tpm-buf.c:208 tpm_buf_read_u8() error: >> uninitialized symbol 'value'. >> drivers/char/tpm/tpm-buf.c:225 tpm_buf_read_u16() error: >> uninitialized symbol 'value'. >> drivers/char/tpm/tpm-buf.c:242 tpm_buf_read_u32() error: >> uninitialized symbol 'value'. >> >> Zero-initialize the return values in tpm_buf_read_u8(), >> tpm_buf_read_u16(), and tpm_buf_read_u32() to guard against >> uninitialized data in case of a boundary overflow. >> >> Add defensive initialization ensures the return values are >> always defined, preventing undefined behavior if the unexpected >> happens. >> >> Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> >> --- >> V1 - https://lore.kernel.org/all/20250409205536.210202-1- >> purvayeshi550@gmail.com/ >> V2 - Update commit message to clarify patch adds a sanity check > > LGTM! > > Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Thank you for the review. > >> >> drivers/char/tpm/tpm-buf.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c >> index e49a19fea3bd..dc882fc9fa9e 100644 >> --- a/drivers/char/tpm/tpm-buf.c >> +++ b/drivers/char/tpm/tpm-buf.c >> @@ -201,7 +201,7 @@ static void tpm_buf_read(struct tpm_buf *buf, >> off_t *offset, size_t count, void >> */ >> u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset) >> { >> - u8 value; >> + u8 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> @@ -218,7 +218,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u8); >> */ >> u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset) >> { >> - u16 value; >> + u16 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> @@ -235,7 +235,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u16); >> */ >> u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset) >> { >> - u32 value; >> + u32 value = 0; >> >> tpm_buf_read(buf, offset, sizeof(value), &value); >> >> -- >> 2.34.1 >> >> > Best Regards, Purva
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c index e49a19fea3bd..dc882fc9fa9e 100644 --- a/drivers/char/tpm/tpm-buf.c +++ b/drivers/char/tpm/tpm-buf.c @@ -201,7 +201,7 @@ static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void */ u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset) { - u8 value; + u8 value = 0; tpm_buf_read(buf, offset, sizeof(value), &value); @@ -218,7 +218,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u8); */ u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset) { - u16 value; + u16 value = 0; tpm_buf_read(buf, offset, sizeof(value), &value); @@ -235,7 +235,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_read_u16); */ u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset) { - u32 value; + u32 value = 0; tpm_buf_read(buf, offset, sizeof(value), &value);
Fix Smatch-detected issue: drivers/char/tpm/tpm-buf.c:208 tpm_buf_read_u8() error: uninitialized symbol 'value'. drivers/char/tpm/tpm-buf.c:225 tpm_buf_read_u16() error: uninitialized symbol 'value'. drivers/char/tpm/tpm-buf.c:242 tpm_buf_read_u32() error: uninitialized symbol 'value'. Zero-initialize the return values in tpm_buf_read_u8(), tpm_buf_read_u16(), and tpm_buf_read_u32() to guard against uninitialized data in case of a boundary overflow. Add defensive initialization ensures the return values are always defined, preventing undefined behavior if the unexpected happens. Signed-off-by: Purva Yeshi <purvayeshi550@gmail.com> --- V1 - https://lore.kernel.org/all/20250409205536.210202-1-purvayeshi550@gmail.com/ V2 - Update commit message to clarify patch adds a sanity check drivers/char/tpm/tpm-buf.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)