35 lines
1.2 KiB
Diff
35 lines
1.2 KiB
Diff
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From d3735e837e3102dfee2d2429c8043c9f4c673383 Mon Sep 17 00:00:00 2001
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From: Colin Ian King <colin.king@canonical.com>
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Date: Wed, 2 Sep 2015 07:27:36 -0400
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Subject: [PATCH 173/203] vcsm: increment res_stats MAP_FAIL stats before we
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potentially release the resource
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resource can be kfree'd when the reference count is zero, so we should
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not bump the res_stats of the resource after the vmcs_sm_release_resource
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call since the resource may have been kfree'd by this call. Instead, bump
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the stats before we call vmcs_sm_release_resource to avoid a potential
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NULL pointer derefernce.
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Bug found using cppcheck static analysis:
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[drivers/char/broadcom/vc_sm/vmcs_sm.c:1373]: (error) Dereferencing
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'resource' after it is deallocated / released
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Signed-off-by: Colin Ian King <colin.king@canonical.com>
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---
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drivers/char/broadcom/vc_sm/vmcs_sm.c | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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--- a/drivers/char/broadcom/vc_sm/vmcs_sm.c
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+++ b/drivers/char/broadcom/vc_sm/vmcs_sm.c
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@@ -1368,8 +1368,8 @@ static int vc_sm_mmap(struct file *file,
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return 0;
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error:
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- vmcs_sm_release_resource(resource, 0);
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resource->res_stats[MAP_FAIL]++;
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+ vmcs_sm_release_resource(resource, 0);
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return ret;
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}
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