From 16e015e533bb1c4c18933114a1d109b1bf6ca087 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 26 Oct 2021 10:34:37 +0200
Subject: dma-buf: st: fix error handling in test_get_fences()
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Git-commit: 55d5e4f98fde7f695fc6c08f46f85ab677f690a2
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

The new driver incorrectly unwinds after errors, as clang points out:

drivers/dma-buf/st-dma-resv.c:295:7: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                if (r) {
                    ^
drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
        while (i--)
               ^
drivers/dma-buf/st-dma-resv.c:295:3: note: remove the 'if' if its condition is always false
                if (r) {
                ^~~~~~~~
drivers/dma-buf/st-dma-resv.c:288:6: error: variable 'i' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
        if (r) {
            ^
drivers/dma-buf/st-dma-resv.c:336:9: note: uninitialized use occurs here
        while (i--)
               ^
drivers/dma-buf/st-dma-resv.c:288:2: note: remove the 'if' if its condition is always false
        if (r) {
        ^~~~~~~~
drivers/dma-buf/st-dma-resv.c:280:10: note: initialize the variable 'i' to silence this warning
        int r, i;
                ^
                 = 0

Skip cleaning up the bits that have not been allocated at this point.

Fixes: 1d51775cd3f5 ("dma-buf: add dma_resv selftest v4")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211026083448.3471055-1-arnd@kernel.org
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/dma-buf/st-dma-resv.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
index 6f3ba756da3e..bc32b3eedcb6 100644
--- a/drivers/dma-buf/st-dma-resv.c
+++ b/drivers/dma-buf/st-dma-resv.c
@@ -287,7 +287,7 @@ static int test_get_fences(void *arg, bool shared)
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
 		pr_err("Resv locking failed\n");
-		goto err_free;
+		goto err_resv;
 	}
 
 	if (shared) {
@@ -295,7 +295,7 @@ static int test_get_fences(void *arg, bool shared)
 		if (r) {
 			pr_err("Resv shared slot allocation failed\n");
 			dma_resv_unlock(&resv);
-			goto err_free;
+			goto err_resv;
 		}
 
 		dma_resv_add_shared_fence(&resv, f);
@@ -336,6 +336,7 @@ static int test_get_fences(void *arg, bool shared)
 	while (i--)
 		dma_fence_put(fences[i]);
 	kfree(fences);
+err_resv:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
 	return r;
-- 
2.38.1