5.4-stable review patch. If anyone has any objections, please let me know.
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From: Qiuxu Zhuo qiuxu.zhuo@intel.com
[ Upstream commit 20d2d476b3ae18041be423671a8637ed5ffd6958 ]
After loading i10nm_edac (which automatically loads skx_edac_common), if unload only i10nm_edac, then reload it and perform error injection testing, a general protection fault may occur:
mce: [Hardware Error]: Machine check events logged Oops: general protection fault ... ... Workqueue: events mce_gen_pool_process RIP: 0010:string+0x53/0xe0 ... Call Trace: <TASK> ? die_addr+0x37/0x90 ? exc_general_protection+0x1e7/0x3f0 ? asm_exc_general_protection+0x26/0x30 ? string+0x53/0xe0 vsnprintf+0x23e/0x4c0 snprintf+0x4d/0x70 skx_adxl_decode+0x16a/0x330 [skx_edac_common] skx_mce_check_error.part.0+0xf8/0x220 [skx_edac_common] skx_mce_check_error+0x17/0x20 [skx_edac_common] ...
The issue arose was because the variable 'adxl_component_count' (inside skx_edac_common), which counts the ADXL components, was not reset. During the reloading of i10nm_edac, the count was incremented by the actual number of ADXL components again, resulting in a count that was double the real number of ADXL components. This led to an out-of-bounds reference to the ADXL component array, causing the general protection fault above.
Fix this issue by resetting the 'adxl_component_count' in adxl_put(), which is called during the unloading of {skx,i10nm}_edac.
Fixes: 123b15863550 ("EDAC, i10nm: make skx_common.o a separate module") Reported-by: Feng Xu feng.f.xu@intel.com Signed-off-by: Qiuxu Zhuo qiuxu.zhuo@intel.com Signed-off-by: Tony Luck tony.luck@intel.com Tested-by: Feng Xu feng.f.xu@intel.com Link: https://lore.kernel.org/r/20250417150724.1170168-2-qiuxu.zhuo@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/edac/skx_common.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/edac/skx_common.c b/drivers/edac/skx_common.c index b298b189bdf35..37d76d591745c 100644 --- a/drivers/edac/skx_common.c +++ b/drivers/edac/skx_common.c @@ -112,6 +112,7 @@ EXPORT_SYMBOL_GPL(skx_adxl_get);
void skx_adxl_put(void) { + adxl_component_count = 0; kfree(adxl_values); kfree(adxl_msg); }