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| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2020-08-18 20:19:32 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-12-03 17:01:14 +0300 |
| commit | 14026b94ccfe626e512bc9fa01e0e72ee75c7a98 (patch) | |
| tree | 99ff430b4360c923d38d322fded53963e2374a99 /include/linux/compat.h | |
| parent | f1cf4f93de2ff66313a091320d7683735816a0bc (diff) | |
| download | linux-14026b94ccfe626e512bc9fa01e0e72ee75c7a98.tar.xz | |
signal: Add unsafe_put_compat_sigset()
Implement 'unsafe' version of put_compat_sigset()
For the bigendian, use unsafe_put_user() directly
to avoid intermediate copy through the stack.
For the littleendian, use a straight unsafe_copy_to_user().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/537c7082ee309a0bb9c67a50c5d9dd929aedb82d.1597770847.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'include/linux/compat.h')
| -rw-r--r-- | include/linux/compat.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/include/linux/compat.h b/include/linux/compat.h index 14d514233e1d..400c0941c8af 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -442,6 +442,38 @@ put_compat_sigset(compat_sigset_t __user *compat, const sigset_t *set, #endif } +#ifdef CONFIG_CPU_BIG_ENDIAN +#define unsafe_put_compat_sigset(compat, set, label) do { \ + compat_sigset_t __user *__c = compat; \ + const sigset_t *__s = set; \ + \ + switch (_NSIG_WORDS) { \ + case 4: \ + unsafe_put_user(__s->sig[3] >> 32, &__c->sig[7], label); \ + unsafe_put_user(__s->sig[3], &__c->sig[6], label); \ + fallthrough; \ + case 3: \ + unsafe_put_user(__s->sig[2] >> 32, &__c->sig[5], label); \ + unsafe_put_user(__s->sig[2], &__c->sig[4], label); \ + fallthrough; \ + case 2: \ + unsafe_put_user(__s->sig[1] >> 32, &__c->sig[3], label); \ + unsafe_put_user(__s->sig[1], &__c->sig[2], label); \ + fallthrough; \ + case 1: \ + unsafe_put_user(__s->sig[0] >> 32, &__c->sig[1], label); \ + unsafe_put_user(__s->sig[0], &__c->sig[0], label); \ + } \ +} while (0) +#else +#define unsafe_put_compat_sigset(compat, set, label) do { \ + compat_sigset_t __user *__c = compat; \ + const sigset_t *__s = set; \ + \ + unsafe_copy_to_user(__c, __s, sizeof(*__c), label); \ +} while (0) +#endif + extern int compat_ptrace_request(struct task_struct *child, compat_long_t request, compat_ulong_t addr, compat_ulong_t data); |