5.4-stable review patch. If anyone has any objections, please let me know.
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From: Greg Kurz groug@kaod.org
[ Upstream commit 8873aab8646194a4446117bb617cc71bddda2dee ]
All these commands end up peeking into the PACA using the user originated cpu id as an index. Check the cpu id is valid in order to prevent xmon to crash. Instead of printing an error, this follows the same behavior as the "lp s #" command : ignore the buggy cpu id parameter and fall back to the #-less version of the command.
Signed-off-by: Greg Kurz groug@kaod.org Reviewed-by: Cédric Le Goater clg@kaod.org Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://msgid.link/161531347060.252863.10490063933688958044.stgit@bahia.lan Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/xmon/xmon.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index 6d130c89fbd85..5991fd06b6525 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -1214,7 +1214,7 @@ static int cpu_cmd(void) unsigned long cpu, first_cpu, last_cpu; int timeout;
- if (!scanhex(&cpu)) { + if (!scanhex(&cpu) || cpu >= num_possible_cpus()) { /* print cpus waiting or in xmon */ printf("cpus stopped:"); last_cpu = first_cpu = NR_CPUS; @@ -2571,7 +2571,7 @@ static void dump_pacas(void)
termch = c; /* Put c back, it wasn't 'a' */
- if (scanhex(&num)) + if (scanhex(&num) && num < num_possible_cpus()) dump_one_paca(num); else dump_one_paca(xmon_owner); @@ -2668,7 +2668,7 @@ static void dump_xives(void)
termch = c; /* Put c back, it wasn't 'a' */
- if (scanhex(&num)) + if (scanhex(&num) && num < num_possible_cpus()) dump_one_xive(num); else dump_one_xive(xmon_owner);