CVE-2024-56631 — scsi: sg: Fix slab-use-after-free read in sg_release()

Affected: Linux, Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP, Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP, Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem, Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

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

scsi: sg: Fix slab-use-after-free read in sg_release()

Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN:

BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407

In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp.

After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error.

Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures:

- No references to sfp or sdp occur after the reference count is decremented.

- Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release().

The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in…

USN-7379-1 — linux, linux-aws, linux-azure, linux-gcp, linux-hwe-6.11, linux-oracle, linux-realtime vulnerabilities

Affected: Ubuntu:24.04:LTS: linux-hwe-6.11

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - MIPS architecture; - PowerPC architecture; - RISC-V architecture; - S390 architecture; - x86 architecture; - Block layer subsystem; - Compute Acceleration Framework; - ACPI drivers; - Drivers core; - Ublk userspace block driver; - Virtio block driver; - Bluetooth drivers; - Buffer Sharing and Synchronization framework; - DMA engine subsystem; - EFI core; - GPIO subsystem; - GPU drivers; - HID subsystem; - Microsoft Hyper-V drivers; - Hardware monitoring drivers; - I3C subsystem; - IIO ADC drivers; - IIO subsystem; - InfiniBand drivers; - IOMMU subsystem; - LED subsystem; - Multiple devices driver; - Media drivers; - Microchip PCI driver; - MTD block device drivers; - Network drivers; - Mellanox network drivers; - STMicroelectronics network drivers; - NVME drivers; - PCI subsystem; - PHY drivers; - Pin controllers subsystem; - x86 platform drivers; - i.MX PM domains; - Power supply drivers; - Voltage and Current Regulator drivers; - SCSI subsystem; - i.MX SoC drivers; - SPI subsystem; - UFS subsystem; - USB Gadget drivers; - TDX Guest driver; - AFS file system; - BTRFS file system; - Ceph distributed file system; - File systems infrastructure; - F2FS file system; - JFFS…

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CVE-2024-56631 — scsi: sg: Fix slab-use-after-free read in sg_release()

USN-7379-1 — linux, linux-aws, linux-azure, linux-gcp, linux-hwe-6.11, linux-oracle, linux-realtime vulnerabilities