From 32d495b384a2db7d23c2295e03e6b6edb1c0db8d Mon Sep 17 00:00:00 2001 From: Purva Yeshi Date: Thu, 10 Apr 2025 16:04:42 +0530 Subject: [PATCH] char: tpm: tpm-buf: Add sanity check fallback in read helpers 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 Reviewed-by: Stefano Garzarella Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- 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); -- 2.25.1