tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: bce9332220bd677d83b19d21502776ad555a0e73 commit: 2f44013e39984c127c6efedf70e6b5f4e9dcf315 erofs: fix pcluster use-after-free on UP platforms date: 3 months ago config: nios2-randconfig-s053-20221205 compiler: nios2-linux-gcc (GCC) 12.1.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.4-39-gce1a6720-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2f44013e39984c127c6efedf70e6b5f4e9dcf315 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 2f44013e39984c127c6efedf70e6b5f4e9dcf315 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=nios2 SHELL=/bin/bash fs/erofs/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot sparse warnings: (new ones prefixed by >>) fs/erofs/utils.c: note: in included file (through include/asm-generic/cmpxchg.h, arch/nios2/include/generated/asm/cmpxchg.h, include/asm-generic/atomic.h, ...): >> include/asm-generic/cmpxchg-local.h:30:42: sparse: sparse: cast truncates bits from constant value (e0f510cc becomes cc) >> include/asm-generic/cmpxchg-local.h:34:44: sparse: sparse: cast truncates bits from constant value (e0f510cc becomes 10cc) -- fs/erofs/zdata.c: note: in included file (through include/asm-generic/cmpxchg.h, arch/nios2/include/generated/asm/cmpxchg.h, include/asm-generic/atomic.h, ...): >> include/asm-generic/cmpxchg-local.h:30:42: sparse: sparse: cast truncates bits from constant value (e0f510cc becomes cc) >> include/asm-generic/cmpxchg-local.h:34:44: sparse: sparse: cast truncates bits from constant value (e0f510cc becomes 10cc) include/asm-generic/cmpxchg-local.h:30:42: sparse: sparse: cast truncates bits from constant value (5f0edead becomes ad) include/asm-generic/cmpxchg-local.h:34:44: sparse: sparse: cast truncates bits from constant value (5f0edead becomes dead) vim +30 include/asm-generic/cmpxchg-local.h 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 7 aa93685afbefa0 Behan Webster 2012-11-20 8 extern unsigned long wrong_size_cmpxchg(volatile void *ptr) aa93685afbefa0 Behan Webster 2012-11-20 9 __noreturn; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 10 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 11 /* 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 12 * Generic version of __cmpxchg_local (disables interrupts). Takes an unsigned 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 13 * long parameter, supporting various types of architectures. 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 14 */ 6988631bdfddce Mark Rutland 2021-05-25 15 static inline unsigned long __generic_cmpxchg_local(volatile void *ptr, 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 16 unsigned long old, unsigned long new, int size) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 17 { 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 18 unsigned long flags, prev; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 19 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 20 /* 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 21 * Sanity checking, compile-time. 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 22 */ 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 23 if (size == 8 && sizeof(unsigned long) != 8) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 24 wrong_size_cmpxchg(ptr); 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 25 5042afe7fe3239 Ingo Molnar 2009-07-03 26 raw_local_irq_save(flags); 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 27 switch (size) { 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 28 case 1: prev = *(u8 *)ptr; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 29 if (prev == old) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 @30 *(u8 *)ptr = (u8)new; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 31 break; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 32 case 2: prev = *(u16 *)ptr; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 33 if (prev == old) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 @34 *(u16 *)ptr = (u16)new; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 35 break; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 36 case 4: prev = *(u32 *)ptr; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 37 if (prev == old) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 38 *(u32 *)ptr = (u32)new; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 39 break; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 40 case 8: prev = *(u64 *)ptr; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 41 if (prev == old) 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 42 *(u64 *)ptr = (u64)new; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 43 break; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 44 default: 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 45 wrong_size_cmpxchg(ptr); 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 46 } 5042afe7fe3239 Ingo Molnar 2009-07-03 47 raw_local_irq_restore(flags); 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 48 return prev; 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 49 } 068fbad288a2c1 Mathieu Desnoyers 2008-02-07 50 :::::: The code at line 30 was first introduced by commit :::::: 068fbad288a2c18b75b0425fb56d241f018a1cb5 Add cmpxchg_local to asm-generic for per cpu atomic operations :::::: TO: Mathieu Desnoyers :::::: CC: Linus Torvalds -- 0-DAY CI Kernel Test Service https://01.org/lkp