arch/arm/kernel/swp_emulate.c:198:14: sparse: sparse: incorrect type in argument 1 (different base types)

From: kernel test robot
Date: Mon Nov 09 2020 - 04:55:47 EST

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: f8394f232b1eab649ce2df5c5f15b0e528c92091
commit: e5fc436f06eef54ef512ea55a9db8eb9f2e76959 sparse: use static inline for __chk_{user,io}_ptr()
date: 2 months ago
config: arm-randconfig-s031-20201105 (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0
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: v0.6.3-76-gf680124b-dirty
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e5fc436f06eef54ef512ea55a9db8eb9f2e76959
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout e5fc436f06eef54ef512ea55a9db8eb9f2e76959
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>


"sparse warnings: (new ones prefixed by >>)"
>> arch/arm/kernel/swp_emulate.c:198:14: sparse: sparse: incorrect type in argument 1 (different base types) @@ expected void const volatile [noderef] __user *ptr @@ got unsigned int @@
>> arch/arm/kernel/swp_emulate.c:198:14: sparse: expected void const volatile [noderef] __user *ptr
arch/arm/kernel/swp_emulate.c:198:14: sparse: got unsigned int

vim +198 arch/arm/kernel/swp_emulate.c

64d2dc384e41e2b Leif Lindholm 2010-09-16 153
64d2dc384e41e2b Leif Lindholm 2010-09-16 154 /*
64d2dc384e41e2b Leif Lindholm 2010-09-16 155 * swp_handler logs the id of calling process, dissects the instruction, sanity
64d2dc384e41e2b Leif Lindholm 2010-09-16 156 * checks the memory location, calls emulate_swpX for the actual operation and
64d2dc384e41e2b Leif Lindholm 2010-09-16 157 * deals with fixup/error handling before returning
64d2dc384e41e2b Leif Lindholm 2010-09-16 158 */
64d2dc384e41e2b Leif Lindholm 2010-09-16 159 static int swp_handler(struct pt_regs *regs, unsigned int instr)
64d2dc384e41e2b Leif Lindholm 2010-09-16 160 {
64d2dc384e41e2b Leif Lindholm 2010-09-16 161 unsigned int address, destreg, data, type;
64d2dc384e41e2b Leif Lindholm 2010-09-16 162 unsigned int res = 0;
64d2dc384e41e2b Leif Lindholm 2010-09-16 163
a8b0ca17b80e92f Peter Zijlstra 2011-06-27 164 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, regs->ARM_pc);
64d2dc384e41e2b Leif Lindholm 2010-09-16 165
c245dcd326fb9f8 Leif Lindholm 2011-12-12 166 res = arm_check_condition(instr, regs->ARM_cpsr);
c245dcd326fb9f8 Leif Lindholm 2011-12-12 167 switch (res) {
c245dcd326fb9f8 Leif Lindholm 2011-12-12 168 case ARM_OPCODE_CONDTEST_PASS:
c245dcd326fb9f8 Leif Lindholm 2011-12-12 169 break;
c245dcd326fb9f8 Leif Lindholm 2011-12-12 170 case ARM_OPCODE_CONDTEST_FAIL:
c245dcd326fb9f8 Leif Lindholm 2011-12-12 171 /* Condition failed - return to next instruction */
c245dcd326fb9f8 Leif Lindholm 2011-12-12 172 regs->ARM_pc += 4;
c245dcd326fb9f8 Leif Lindholm 2011-12-12 173 return 0;
c245dcd326fb9f8 Leif Lindholm 2011-12-12 174 case ARM_OPCODE_CONDTEST_UNCOND:
c245dcd326fb9f8 Leif Lindholm 2011-12-12 175 /* If unconditional encoding - not a SWP, undef */
c245dcd326fb9f8 Leif Lindholm 2011-12-12 176 return -EFAULT;
c245dcd326fb9f8 Leif Lindholm 2011-12-12 177 default:
c245dcd326fb9f8 Leif Lindholm 2011-12-12 178 return -EINVAL;
c245dcd326fb9f8 Leif Lindholm 2011-12-12 179 }
c245dcd326fb9f8 Leif Lindholm 2011-12-12 180
64d2dc384e41e2b Leif Lindholm 2010-09-16 181 if (current->pid != previous_pid) {
64d2dc384e41e2b Leif Lindholm 2010-09-16 182 pr_debug("\"%s\" (%ld) uses deprecated SWP{B} instruction\n",
64d2dc384e41e2b Leif Lindholm 2010-09-16 183 current->comm, (unsigned long)current->pid);
64d2dc384e41e2b Leif Lindholm 2010-09-16 184 previous_pid = current->pid;
64d2dc384e41e2b Leif Lindholm 2010-09-16 185 }
64d2dc384e41e2b Leif Lindholm 2010-09-16 186
64d2dc384e41e2b Leif Lindholm 2010-09-16 187 address = regs->uregs[EXTRACT_REG_NUM(instr, RN_OFFSET)];
64d2dc384e41e2b Leif Lindholm 2010-09-16 188 data = regs->uregs[EXTRACT_REG_NUM(instr, RT2_OFFSET)];
64d2dc384e41e2b Leif Lindholm 2010-09-16 189 destreg = EXTRACT_REG_NUM(instr, RT_OFFSET);
64d2dc384e41e2b Leif Lindholm 2010-09-16 190
64d2dc384e41e2b Leif Lindholm 2010-09-16 191 type = instr & TYPE_SWPB;
64d2dc384e41e2b Leif Lindholm 2010-09-16 192
64d2dc384e41e2b Leif Lindholm 2010-09-16 193 pr_debug("addr in r%d->0x%08x, dest is r%d, source in r%d->0x%08x)\n",
64d2dc384e41e2b Leif Lindholm 2010-09-16 194 EXTRACT_REG_NUM(instr, RN_OFFSET), address,
64d2dc384e41e2b Leif Lindholm 2010-09-16 195 destreg, EXTRACT_REG_NUM(instr, RT2_OFFSET), data);
64d2dc384e41e2b Leif Lindholm 2010-09-16 196
64d2dc384e41e2b Leif Lindholm 2010-09-16 197 /* Check access in reasonable access range for both SWP and SWPB */
96d4f267e40f950 Linus Torvalds 2019-01-03 @198 if (!access_ok((address & ~3), 4)) {
64d2dc384e41e2b Leif Lindholm 2010-09-16 199 pr_debug("SWP{B} emulation: access to %p not allowed!\n",
64d2dc384e41e2b Leif Lindholm 2010-09-16 200 (void *)address);
64d2dc384e41e2b Leif Lindholm 2010-09-16 201 res = -EFAULT;
64d2dc384e41e2b Leif Lindholm 2010-09-16 202 } else {
64d2dc384e41e2b Leif Lindholm 2010-09-16 203 res = emulate_swpX(address, &data, type);
64d2dc384e41e2b Leif Lindholm 2010-09-16 204 }
64d2dc384e41e2b Leif Lindholm 2010-09-16 205
64d2dc384e41e2b Leif Lindholm 2010-09-16 206 if (res == 0) {
64d2dc384e41e2b Leif Lindholm 2010-09-16 207 /*
64d2dc384e41e2b Leif Lindholm 2010-09-16 208 * On successful emulation, revert the adjustment to the PC
64d2dc384e41e2b Leif Lindholm 2010-09-16 209 * made in kernel/traps.c in order to resume execution at the
64d2dc384e41e2b Leif Lindholm 2010-09-16 210 * instruction following the SWP{B}.
64d2dc384e41e2b Leif Lindholm 2010-09-16 211 */
64d2dc384e41e2b Leif Lindholm 2010-09-16 212 regs->ARM_pc += 4;
64d2dc384e41e2b Leif Lindholm 2010-09-16 213 regs->uregs[destreg] = data;
64d2dc384e41e2b Leif Lindholm 2010-09-16 214 } else if (res == -EFAULT) {
64d2dc384e41e2b Leif Lindholm 2010-09-16 215 /*
64d2dc384e41e2b Leif Lindholm 2010-09-16 216 * Memory errors do not mean emulation failed.
64d2dc384e41e2b Leif Lindholm 2010-09-16 217 * Set up signal info to return SEGV, then return OK
64d2dc384e41e2b Leif Lindholm 2010-09-16 218 */
64d2dc384e41e2b Leif Lindholm 2010-09-16 219 set_segfault(regs, address);
64d2dc384e41e2b Leif Lindholm 2010-09-16 220 }
64d2dc384e41e2b Leif Lindholm 2010-09-16 221
64d2dc384e41e2b Leif Lindholm 2010-09-16 222 return 0;
64d2dc384e41e2b Leif Lindholm 2010-09-16 223 }
64d2dc384e41e2b Leif Lindholm 2010-09-16 224

:::::: The code at line 198 was first introduced by commit
:::::: 96d4f267e40f9509e8a66e2b39e8b95655617693 Remove 'type' argument from access_ok() function

:::::: TO: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
:::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
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