This is a note to let you know that I've just added the patch titled perf/x86/intel/uncore: Fix NULL pointer dereference issue in upi_fill_topology() to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-x86-intel-uncore-fix-null-pointer-dereference-i.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 79f5c7ca9565145d61cd63320858c7f1e687588c Author: Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx> Date: Mon Nov 27 10:52:45 2023 -0800 perf/x86/intel/uncore: Fix NULL pointer dereference issue in upi_fill_topology() [ Upstream commit 1692cf434ba13ee212495b5af795b6a07e986ce4 ] Get logical socket id instead of physical id in discover_upi_topology() to avoid out-of-bound access on 'upi = &type->topology[nid][idx];' line that leads to NULL pointer dereference in upi_fill_topology() Fixes: f680b6e6062e ("perf/x86/intel/uncore: Enable UPI topology discovery for Icelake Server") Reported-by: Kyle Meyer <kyle.meyer@xxxxxxx> Signed-off-by: Alexander Antonov <alexander.antonov@xxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Tested-by: Kyle Meyer <kyle.meyer@xxxxxxx> Link: https://lore.kernel.org/r/20231127185246.2371939-2-alexander.antonov@xxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/events/intel/uncore_snbep.c b/arch/x86/events/intel/uncore_snbep.c index 8250f0f59c2b..49bc27ab26ad 100644 --- a/arch/x86/events/intel/uncore_snbep.c +++ b/arch/x86/events/intel/uncore_snbep.c @@ -5596,7 +5596,7 @@ static int discover_upi_topology(struct intel_uncore_type *type, int ubox_did, i struct pci_dev *ubox = NULL; struct pci_dev *dev = NULL; u32 nid, gid; - int i, idx, ret = -EPERM; + int i, idx, lgc_pkg, ret = -EPERM; struct intel_uncore_topology *upi; unsigned int devfn; @@ -5614,8 +5614,13 @@ static int discover_upi_topology(struct intel_uncore_type *type, int ubox_did, i for (i = 0; i < 8; i++) { if (nid != GIDNIDMAP(gid, i)) continue; + lgc_pkg = topology_phys_to_logical_pkg(i); + if (lgc_pkg < 0) { + ret = -EPERM; + goto err; + } for (idx = 0; idx < type->num_boxes; idx++) { - upi = &type->topology[nid][idx]; + upi = &type->topology[lgc_pkg][idx]; devfn = PCI_DEVFN(dev_link0 + idx, ICX_UPI_REGS_ADDR_FUNCTION); dev = pci_get_domain_bus_and_slot(pci_domain_nr(ubox->bus), ubox->bus->number, @@ -5626,6 +5631,7 @@ static int discover_upi_topology(struct intel_uncore_type *type, int ubox_did, i goto err; } } + break; } } err: