mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
tpm: vtpm_proxy: Check length to avoid compiler warning
When building with -Warray-bounds under GCC 11.2, this warning was emitted: In function 'memset', inlined from 'vtpm_proxy_fops_read' at drivers/char/tpm/tpm_vtpm_proxy.c:102:2: ./include/linux/fortify-string.h:43:33: warning: '__builtin_memset' pointer overflow between offset 164 and size [2147483648, 4294967295] [-Warray-bounds] 43 | #define __underlying_memset __builtin_memset | ^ This warning appears to be triggered due to the "count < len" check in vtpm_proxy_fops_read() splitting the CFG[1], and the compiler attempting to reason about the possible value range in len compared to the buffer size. In order to silence this warning, and to keep this code robust if the use of proxy_dev->req_len ever changes in the future, explicitly check the size of len before reaching the memset(). [1] https://lore.kernel.org/lkml/CAG48ez1iTF9KegKJrW5a3WzXgCPZJ73nS2_e5esKJRppdzvv8g@mail.gmail.com Cc: Peter Huewe <peterhuewe@gmx.de> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: linux-integrity@vger.kernel.org Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Link: https://lore.kernel.org/lkml/4b59d305-6858-1514-751a-37853ad777be@linux.ibm.com Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220119184354.3367603-1-keescook@chromium.org
This commit is contained in:
parent
545c272232
commit
e52432e164
1 changed files with 1 additions and 1 deletions
|
@ -91,7 +91,7 @@ static ssize_t vtpm_proxy_fops_read(struct file *filp, char __user *buf,
|
|||
|
||||
len = proxy_dev->req_len;
|
||||
|
||||
if (count < len) {
|
||||
if (count < len || len > sizeof(proxy_dev->buffer)) {
|
||||
mutex_unlock(&proxy_dev->buf_lock);
|
||||
pr_debug("Invalid size in recv: count=%zd, req_len=%zd\n",
|
||||
count, len);
|
||||
|
|
Loading…
Reference in a new issue