From: Colin Ian King <>

Change predecrement compare to post decrement compare to avoid an
unsigned integer wrap-around comparisomn when decrementing in the while

For example, if the debugfs_create_file fails when i is zero, the
current situation will predecrement i in the while loop, wrapping i
to the maximum signed integer and cause multiple out of bounds reads
on dfs_fls[i].d as the loop interates to zero.

Also, as Borislav Petkov suggested, return -ENODEV rather than -ENOMEM
on the error condition.

Signed-off-by: Colin Ian King <>
 arch/x86/ras/mce_amd_inj.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/ras/mce_amd_inj.c b/arch/x86/ras/mce_amd_inj.c
index cd318d9..20b227f 100644
--- a/arch/x86/ras/mce_amd_inj.c
+++ b/arch/x86/ras/mce_amd_inj.c
@@ -464,13 +464,13 @@ static int __init init_mce_inject(void)
        return 0;
-       while (--i >= 0)
+       while (i-- > 0)
        dfs_inj = NULL;
-       return -ENOMEM;
+       return -ENODEV;
 static void __exit exit_mce_inject(void)

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