The patch below does not apply to the 3.7-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1da80cfa8727abf404fcee44d04743febea54069 Mon Sep 17 00:00:00 2001
From: Ilija Hadzic <ihad...@research.bell-labs.com>
Date: Wed, 23 Jan 2013 13:59:05 -0500
Subject: [PATCH] drm/radeon: fix a rare case of double kfree
If one (but not both) allocations of p->chunks[].kpage[]
in radeon_cs_parser_init fail, the error path will free
the successfully allocated page, but leave a stale pointer
value in the kpage[] field. This will later cause a
double-free when radeon_cs_parser_fini is called.
This patch fixes the issue by forcing both pointers to NULL
after kfree in the error path.
The circumstances under which the problem happens are very
rare. The card must be AGP and the system must run out of
kmalloc area just at the right time so that one allocation
succeeds, while the other fails.
Signed-off-by: Ilija Hadzic <ihad...@research.bell-labs.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesin...@canonical.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/gpu/drm/radeon/radeon_cs.c
b/drivers/gpu/drm/radeon/radeon_cs.c
index 469661f..5407459 100644
--- a/drivers/gpu/drm/radeon/radeon_cs.c
+++ b/drivers/gpu/drm/radeon/radeon_cs.c
@@ -286,6 +286,8 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void
*data)
p->chunks[p->chunk_ib_idx].kpage[1] == NULL) {
kfree(p->chunks[p->chunk_ib_idx].kpage[0]);
kfree(p->chunks[p->chunk_ib_idx].kpage[1]);
+ p->chunks[p->chunk_ib_idx].kpage[0] = NULL;
+ p->chunks[p->chunk_ib_idx].kpage[1] = NULL;
return -ENOMEM;
}
}
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
