The patch titled
Subject: lib/stackdepot.c: fix a condition in stack_depot_fetch()
has been added to the -mm tree. Its filename is
stackdepot-check-depot_index-before-accessing-the-stack-slab-fix.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/stackdepot-check-depot_index-before-accessing-the-stack-slab-fix.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/stackdepot-check-depot_index-before-accessing-the-stack-slab-fix.patch
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------------------------------------------------------
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Subject: lib/stackdepot.c: fix a condition in stack_depot_fetch()
We should check for a NULL pointer first before adding the offset.
Otherwise if the pointer is NULL and the offset is non-zero, it will lead
to an Oops.
Link: http://lkml.kernel.org/r/20200312113006.GA20562@mwanda
Fixes: d45048e65a59 ("lib/stackdepot.c: check depot_index before accessing the stack slab")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Alexander Potapenko <glider@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/stackdepot.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
--- a/lib/stackdepot.c~stackdepot-check-depot_index-before-accessing-the-stack-slab-fix
+++ a/lib/stackdepot.c
@@ -206,18 +206,16 @@ unsigned int stack_depot_fetch(depot_sta
size_t offset = parts.offset << STACK_ALLOC_ALIGN;
struct stack_record *stack;
+ *entries = NULL;
if (parts.slabindex > depot_index) {
WARN(1, "slab index %d out of bounds (%d) for stack id %08x\n",
parts.slabindex, depot_index, handle);
- *entries = NULL;
return 0;
}
slab = stack_slabs[parts.slabindex];
- stack = slab + offset;
- if (!stack) {
- *entries = NULL;
+ if (!slab)
return 0;
- }
+ stack = slab + offset;
*entries = stack->entries;
return stack->size;
_
Patches currently in -mm which might be from dan.carpenter@xxxxxxxxxx are
stackdepot-check-depot_index-before-accessing-the-stack-slab-fix.patch
lib-test_kmod-remove-a-null-test.patch
