[ 28/61] isdn/gigaset: fix zero size border case in debug dump

From: Greg Kroah-Hartman
Date: Tue Feb 12 2013 - 16:04:39 EST


3.7-stable review patch. If anyone has any objections, please let me know.

------------------


From: Tilman Schmidt <tilman@xxxxxxx>

[ Upstream commit d721a1752ba544df8d7d36959038b26bc92bdf80 ]

If subtracting 12 from l leaves zero we'd do a zero size allocation,
leading to an oops later when we try to set the NUL terminator.

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Tilman Schmidt <tilman@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/isdn/gigaset/capi.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/isdn/gigaset/capi.c
+++ b/drivers/isdn/gigaset/capi.c
@@ -248,6 +248,8 @@ static inline void dump_rawmsg(enum debu
CAPIMSG_APPID(data), CAPIMSG_MSGID(data), l,
CAPIMSG_CONTROL(data));
l -= 12;
+ if (l <= 0)
+ return;
dbgline = kmalloc(3 * l, GFP_ATOMIC);
if (!dbgline)
return;


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