In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Clean up only new IRQ glue on request_irq() failure
The mlx5_irq_alloc() function can inadvertently free the entire rmap and end up in a crash[1] when the other threads tries to access this, when request_irq() fails due to exhausted IRQ vectors. This commit modifies the cleanup to remove only the specific IRQ mapping that was just added.
This prevents removal of other valid mappings and ensures precise cleanup of the failed IRQ allocation's associated glue object.
Note: This error is observed when both fwctl and rds configs are enabled.
[1] mlx5_core 0000:05:00.0: Successfully registered panic handler for port 1 mlx5_core 0000:05:00.0: mlx5_irq_alloc:293:(pid 66740): Failed to request irq. err = -28 infiniband mlx5_0: mlx5_ib_test_wc:290:(pid 66740): Error -28 while trying to test write-combining support mlx5_core 0000:05:00.0: Successfully unregistered panic handler for port 1 mlx5_core 0000:06:00.0: Successfully registered panic handler for port 1 mlx5_core 0000:06:00.0: mlx5_irq_alloc:293:(pid 66740): Failed to request irq. err = -28 infiniband mlx5_0: mlx5_ib_test_wc:290:(pid 66740): Error -28 while trying to test write-combining support mlx5_core 0000:06:00.0: Successfully unregistered panic handler for port 1 mlx5_core 0000:03:00.0: mlx5_irq_alloc:293:(pid 28895): Failed to request irq. err = -28 mlx5_core 0000:05:00.0: mlx5_irq_alloc:293:(pid 28895): Failed to request irq. err = -28 general protection fault, probably for non-canonical address 0xe277a58fde16f291: 0000 [#1] SMP NOPTI
RIP: 0010:free_irq_cpu_rmap+0x23/0x7d Call Trace: <TASK> ? show_trace_log_lvl+0x1d6/0x2f9 ? show_trace_log_lvl+0x1d6/0x2f9 ? mlx5_irq_alloc.cold+0x5d/0xf3 [mlx5_core] ? __die_body.cold+0x8/0xa ? die_addr+0x39/0x53 ? exc_general_protection+0x1c4/0x3e9 ? dev_vprintk_emit+0x5f/0x90 ? asm_exc_general_protection+0x22/0x27 ? free_irq_cpu_rmap+0x23/0x7d...