find_vma() will continue to search upwards until the end of the virtual
memory space.  This means the si_code would almost never be set to
SEGV_MAPERR even when the address falls outside of any VMA.  The result
is that the si_code is not reliable as it may or may not be set to the
correct result, depending on where the address falls in the address

Using find_vma_intersection() allows for what is intended by only
returning a VMA if it falls within the range provided, in this case a
window of 1.

Fixes: bd35a4adc413 (arm64: Port SWP/SWPB emulation support from arm)
Signed-off-by: Liam R. Howlett <>
 arch/arm64/kernel/traps.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index a05d34f0e82a..a44007904a64 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -383,9 +383,10 @@ void force_signal_inject(int signal, int code, unsigned 
long address, unsigned i
 void arm64_notify_segfault(unsigned long addr)
        int code;
+       unsigned long ut_addr = untagged_addr(addr);
-       if (find_vma(current->mm, untagged_addr(addr)) == NULL)
+       if (find_vma_intersection(current->mm, ut_addr, ut_addr + 1) == NULL)
                code = SEGV_MAPERR;
                code = SEGV_ACCERR;

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