6.12-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Weißschuh thomas.weissschuh@linutronix.de
commit 15e2f65f2ecfeb8e39315522e2b5cfdc5651fc10 upstream.
"resource->end" needs to always be equal to "resource->start + size - 1". The previous version of the function did not perform the "- 1" in case of an empty resource.
Also make sure to allow an empty resource at address 0.
Reported-by: Basharath Hussain Khaja basharath@couthit.com Closes: https://lore.kernel.org/lkml/20250108140414.13530-1-basharath@couthit.com/ Fixes: 1a52a094c2f0 ("of: address: Unify resource bounds overflow checking") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de Link: https://lore.kernel.org/r/20250120-of-address-overflow-v1-1-dd68dbf47bce@lin... Signed-off-by: Rob Herring (Arm) robh@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/of/address.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
--- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -200,17 +200,15 @@ static u64 of_bus_pci_map(__be32 *addr,
static int __of_address_resource_bounds(struct resource *r, u64 start, u64 size) { - u64 end = start; - if (overflows_type(start, r->start)) return -EOVERFLOW; - if (size && check_add_overflow(end, size - 1, &end)) - return -EOVERFLOW; - if (overflows_type(end, r->end)) - return -EOVERFLOW;
r->start = start; - r->end = end; + + if (!size) + r->end = wrapping_sub(typeof(r->end), r->start, 1); + else if (size && check_add_overflow(r->start, size - 1, &r->end)) + return -EOVERFLOW;
return 0; }