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author | Helge Deller <deller@gmx.de> | 2022-02-13 22:52:11 +0100 |
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committer | Helge Deller <deller@gmx.de> | 2022-02-14 12:36:42 +0100 |
commit | dbd0b42350d5717786cb8257fbe5b528f3af9772 (patch) | |
tree | 5bda5a8d048534d584756ae593337a3df5d77314 /arch/parisc | |
parent | b160628e9ebcdc85d0db9d7f423c26b3c7c179d0 (diff) | |
download | linux-stable-dbd0b42350d5717786cb8257fbe5b528f3af9772.tar.gz linux-stable-dbd0b42350d5717786cb8257fbe5b528f3af9772.tar.bz2 linux-stable-dbd0b42350d5717786cb8257fbe5b528f3af9772.zip |
parisc: Fix some apparent put_user() failures
After commit 4b9d2a731c3d ("parisc: Switch user access functions
to signal errors in r29 instead of r8") bash suddenly started
to report those warnings after login:
-bash: cannot set terminal process group (-1): Bad file descriptor
-bash: no job control in this shell
It turned out, that a function call inside a put_user(), e.g.:
put_user(vt_do_kdgkbmode(console), (int __user *)arg);
clobbered the error register (r29) and thus the put_user() call itself
seem to have failed.
Rearrange the C-code to pre-calculate the intermediate value
and then do the put_user().
Additionally prefer the "+" constraint on pu_err and gu_err registers
to tell the compiler that those operands are both read and written by
the assembly instruction.
Reported-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 4b9d2a731c3d ("parisc: Switch user access functions to signal errors in r29 instead of r8")
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
-rw-r--r-- | arch/parisc/include/asm/uaccess.h | 29 |
1 files changed, 15 insertions, 14 deletions
diff --git a/arch/parisc/include/asm/uaccess.h b/arch/parisc/include/asm/uaccess.h index ebf8a845b017..123d5f16cd9d 100644 --- a/arch/parisc/include/asm/uaccess.h +++ b/arch/parisc/include/asm/uaccess.h @@ -89,8 +89,8 @@ struct exception_table_entry { __asm__("1: " ldx " 0(" sr "%2),%0\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ - : "=r"(__gu_val), "=r"(__gu_err) \ - : "r"(ptr), "1"(__gu_err)); \ + : "=r"(__gu_val), "+r"(__gu_err) \ + : "r"(ptr)); \ \ (val) = (__force __typeof__(*(ptr))) __gu_val; \ } @@ -123,8 +123,8 @@ struct exception_table_entry { "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ - : "=&r"(__gu_tmp.l), "=r"(__gu_err) \ - : "r"(ptr), "1"(__gu_err)); \ + : "=&r"(__gu_tmp.l), "+r"(__gu_err) \ + : "r"(ptr)); \ \ (val) = __gu_tmp.t; \ } @@ -135,13 +135,12 @@ struct exception_table_entry { #define __put_user_internal(sr, x, ptr) \ ({ \ ASM_EXCEPTIONTABLE_VAR(__pu_err); \ - __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \ \ switch (sizeof(*(ptr))) { \ - case 1: __put_user_asm(sr, "stb", __x, ptr); break; \ - case 2: __put_user_asm(sr, "sth", __x, ptr); break; \ - case 4: __put_user_asm(sr, "stw", __x, ptr); break; \ - case 8: STD_USER(sr, __x, ptr); break; \ + case 1: __put_user_asm(sr, "stb", x, ptr); break; \ + case 2: __put_user_asm(sr, "sth", x, ptr); break; \ + case 4: __put_user_asm(sr, "stw", x, ptr); break; \ + case 8: STD_USER(sr, x, ptr); break; \ default: BUILD_BUG(); \ } \ \ @@ -150,7 +149,9 @@ struct exception_table_entry { #define __put_user(x, ptr) \ ({ \ - __put_user_internal("%%sr3,", x, ptr); \ + __typeof__(&*(ptr)) __ptr = ptr; \ + __typeof__(*(__ptr)) __x = (__typeof__(*(__ptr)))(x); \ + __put_user_internal("%%sr3,", __x, __ptr); \ }) #define __put_kernel_nofault(dst, src, type, err_label) \ @@ -180,8 +181,8 @@ struct exception_table_entry { "1: " stx " %2,0(" sr "%1)\n" \ "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ - : "=r"(__pu_err) \ - : "r"(ptr), "r"(x), "0"(__pu_err)) + : "+r"(__pu_err) \ + : "r"(ptr), "r"(x)) #if !defined(CONFIG_64BIT) @@ -193,8 +194,8 @@ struct exception_table_entry { "9:\n" \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ - : "=r"(__pu_err) \ - : "r"(ptr), "r"(__val), "0"(__pu_err)); \ + : "+r"(__pu_err) \ + : "r"(ptr), "r"(__val)); \ } while (0) #endif /* !defined(CONFIG_64BIT) */ |