Linux CVE-2024-58056

In the Linux kernel, the following vulnerability has been resolved:

remoteproc: core: Fix ida_free call while not allocated

In the rproc_alloc() function, on error, put_device(&rproc->dev) is called, leading to the call of the rproc_type_release() function. An error can occurs before ida_alloc is called.

In such case in rproc_type_release(), the condition (rproc->index >= 0) is true as rproc->index has been initialized to 0. ida_free() is called reporting a warning: [ 4.181906] WARNING: CPU: 1 PID: 24 at lib/idr.c:525 ida_free+0x100/0x164 [ 4.186378] stm32-display-dsi 5a000000.dsi: Fixed dependency cycle(s) with /soc/dsi@5a000000/panel@0 [ 4.188854] ida_free called for id=0 which is not allocated. [ 4.198256] mipi-dsi 5a000000.dsi.0: Fixed dependency cycle(s) with /soc/dsi@5a000000 [ 4.203556] Modules linked in: panel_orisetech_otm8009a dw_mipi_dsi_stm(+) gpu_sched dw_mipi_dsi stm32_rproc stm32_crc32 stm32_ipcc(+) optee(+) [ 4.224307] CPU: 1 UID: 0 PID: 24 Comm: kworker/u10:0 Not tainted 6.12.0 #442 [ 4.231481] Hardware name: STM32 (Device Tree Support) [ 4.236627] Workqueue: events_unbound deferred_probe_work_func [ 4.242504] Call trace: [ 4.242522] unwind_backtrace from show_stack+0x10/0x14 [ 4.250218] show_stack from dump_stack_lvl+0x50/0x64 [ 4.255274] dump_stack_lvl from __warn+0x80/0x12c [ 4.260134] __warn from warn_slowpath_fmt+0x114/0x188 [ 4.265199] warn_slowpath_fmt from ida_free+0x100/0x164 [ 4.270565] ida_free from rproc_type_release+0x38/0x60 [ 4.275832] rproc_type_release from device_release+0x30/0xa0 [ 4.281601] device_release from kobject_put+0xc4/0x294 [ 4.286762] kobject_put from rproc_alloc.part.0+0x208/0x28c [ 4.292430] rproc_alloc.part.0 from devm_rproc_alloc+0x80/0xc4 [ 4.298393] devm_rproc_alloc from stm32_rproc_probe+0xd0/0x844 [stm32_rproc] [ 4.305575] stm32_rproc_probe [stm32_rproc] from platform_probe+0x5c/0xbc

Calling ida_alloc earlier in rproc_alloc ensures that the rproc->index is properly set.