From: Jakob Koschel jkl820.git@gmail.com
[ Upstream commit e9a1cc2e4c4ee7c7e60fb26345618c2522a2a10f ]
The code implicitly assumes that the list iterator finds a correct handle. If 'vsi_handle' is not found the 'old_agg_vsi_info' was pointing to an bogus memory location. For safety a separate list iterator variable should be used to make the != NULL check on 'old_agg_vsi_info' correct under any circumstances.
Additionally Linus proposed to avoid any use of the list iterator variable after the loop, in the attempt to move the list iterator variable declaration into the macro to avoid any potential misuse after the loop. Using it in a pointer comparison after the loop is undefined behavior and should be omitted if possible [1].
Fixes: 37c592062b16 ("ice: remove the VSI info from previous agg") Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWX... [1] Signed-off-by: Jakob Koschel jkl820.git@gmail.com Tested-by: Arpana Arland arpanax.arland@intel.com (A Contingent worker at Intel) Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/ice/ice_sched.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_sched.c b/drivers/net/ethernet/intel/ice/ice_sched.c index 118595763bba3..2c62c1763ee0d 100644 --- a/drivers/net/ethernet/intel/ice/ice_sched.c +++ b/drivers/net/ethernet/intel/ice/ice_sched.c @@ -2756,7 +2756,7 @@ static int ice_sched_assoc_vsi_to_agg(struct ice_port_info *pi, u32 agg_id, u16 vsi_handle, unsigned long *tc_bitmap) { - struct ice_sched_agg_vsi_info *agg_vsi_info, *old_agg_vsi_info = NULL; + struct ice_sched_agg_vsi_info *agg_vsi_info, *iter, *old_agg_vsi_info = NULL; struct ice_sched_agg_info *agg_info, *old_agg_info; struct ice_hw *hw = pi->hw; int status = 0; @@ -2774,11 +2774,13 @@ ice_sched_assoc_vsi_to_agg(struct ice_port_info *pi, u32 agg_id, if (old_agg_info && old_agg_info != agg_info) { struct ice_sched_agg_vsi_info *vtmp;
- list_for_each_entry_safe(old_agg_vsi_info, vtmp, + list_for_each_entry_safe(iter, vtmp, &old_agg_info->agg_vsi_list, list_entry) - if (old_agg_vsi_info->vsi_handle == vsi_handle) + if (iter->vsi_handle == vsi_handle) { + old_agg_vsi_info = iter; break; + } }
/* check if entry already exist */