From 0356cc5d27c239892809dcb97464850d6badbad8 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Fri, 15 Oct 2021 00:03:45 -0500 Subject: [PATCH] powerpc/vas: Fix potential NULL pointer dereference commit 61cb9ac66b30374c7fd8a8b2a3c4f8f432c72e36 upstream. (!ptr && !ptr->foo) strikes again. :) The expression (!ptr && !ptr->foo) is bogus and in case ptr is NULL, it leads to a NULL pointer dereference: ptr->foo. Fix this by converting && to || This issue was detected with the help of Coccinelle, and audited and fixed manually. Fixes: 1a0d0d5ed5e3 ("powerpc/vas: Add platform specific user window operations") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Reviewed-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211015050345.GA1161918@embeddedor Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/platforms/book3s/vas-api.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/book3s/vas-api.c b/arch/powerpc/platforms/book3s/vas-api.c index 30172e52e16b..4d82c92ddd52 100644 --- a/arch/powerpc/platforms/book3s/vas-api.c +++ b/arch/powerpc/platforms/book3s/vas-api.c @@ -303,7 +303,7 @@ static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg) return -EINVAL; } - if (!cp_inst->coproc->vops && !cp_inst->coproc->vops->open_win) { + if (!cp_inst->coproc->vops || !cp_inst->coproc->vops->open_win) { pr_err("VAS API is not registered\n"); return -EACCES; } @@ -373,7 +373,7 @@ static int coproc_mmap(struct file *fp, struct vm_area_struct *vma) return -EINVAL; } - if (!cp_inst->coproc->vops && !cp_inst->coproc->vops->paste_addr) { + if (!cp_inst->coproc->vops || !cp_inst->coproc->vops->paste_addr) { pr_err("%s(): VAS API is not registered\n", __func__); return -EACCES; }