3.2-stable review patch. If anyone has any objections, please let me know.
------------------ From: Yi Zou <[email protected]> commit d0e27c88d795fb9647153063ec48051fd84e1731 upstream. I am hitting this bug when the target is low in memory that fails the alloc_page() for the newly submitted command. This is a sort of off-by-one bug causing NULL pointer dereference in __free_page() since 'i' here is really the counter of total pages that have been successfully allocated here. Signed-off-by: Yi Zou <[email protected]> Cc: Andy Grover <[email protected]> Cc: Nicholas Bellinger <[email protected]> Cc: Open-FCoE.org <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/target/target_core_transport.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 0eaae23..a7589cc 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2294,9 +2294,9 @@ transport_generic_get_mem(struct se_cmd *cmd) return 0; out: - while (i >= 0) { - __free_page(sg_page(&cmd->t_data_sg[i])); + while (i > 0) { i--; + __free_page(sg_page(&cmd->t_data_sg[i])); } kfree(cmd->t_data_sg); cmd->t_data_sg = NULL; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
