On Fri, Dec 13, 2024 at 11:44:22AM +0800, haixiao.yan.cn@eng.windriver.com wrote:
From: Nathan Lynch nathanl@linux.ibm.com
[ Upstream commit 0974d03eb479384466d828d65637814bee6b26d7 ]
Smatch warns:
arch/powerpc/kernel/rtas.c:1932 __do_sys_rtas() warn: potential spectre issue 'args.args' [r] (local cap)
The 'nargs' and 'nret' locals come directly from a user-supplied buffer and are used as indexes into a small stack-based array and as inputs to copy_to_user() after they are subject to bounds checks.
Use array_index_nospec() after the bounds checks to clamp these values for speculative execution.
Signed-off-by: Nathan Lynch nathanl@linux.ibm.com Reported-by: Breno Leitao leitao@debian.org Reviewed-by: Breno Leitao leitao@debian.org Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/20240530-sys_rtas-nargs-nret-v1-1-129acddd4d89@linux.ibm.... Signed-off-by: Haixiao Yan haixiao.yan.cn@windriver.com
This commit is backporting 0974d03eb479 to the branch linux-5.15.y to solve the CVE-2024-46774.
Now deleted, please see: https://lore.kernel.org/r/2024121322-conjuror-gap-b542@gregkh for what you all need to do, TOGETHER, to get this fixed and so that I can accept patches from your company in the future.
thanks,
greg k-h