4.17-stable review patch. If anyone has any objections, please let me know.
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From: David Rivshin DRivshin@allworx.com
commit 76ed0b803a2ab793a1b27d1dfe0de7955282cd34 upstream.
NUMREGBYTES (which is used as the size for gdb_regs[]) is incorrectly based on DBG_MAX_REG_NUM instead of GDB_MAX_REGS. DBG_MAX_REG_NUM is the number of total registers, while GDB_MAX_REGS is the number of 'unsigned longs' it takes to serialize those registers. Since FP registers require 3 'unsigned longs' each, DBG_MAX_REG_NUM is smaller than GDB_MAX_REGS.
This causes GDB 8.0 give the following error on connect: "Truncated register 19 in remote 'g' packet"
This also causes the register serialization/deserialization logic to overflow gdb_regs[], overwriting whatever follows.
Fixes: 834b2964b7ab ("kgdb,arm: fix register dump") Cc: stable@vger.kernel.org # 2.6.37+ Signed-off-by: David Rivshin drivshin@allworx.com Acked-by: Rabin Vincent rabin@rab.in Tested-by: Daniel Thompson daniel.thompson@linaro.org Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm/include/asm/kgdb.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm/include/asm/kgdb.h +++ b/arch/arm/include/asm/kgdb.h @@ -77,7 +77,7 @@ extern int kgdb_fault_expected;
#define KGDB_MAX_NO_CPUS 1 #define BUFMAX 400 -#define NUMREGBYTES (DBG_MAX_REG_NUM << 2) +#define NUMREGBYTES (GDB_MAX_REGS << 2) #define NUMCRITREGBYTES (32 << 2)
#define _R0 0