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| author | Dmitry Chagin <dchagin@FreeBSD.org> | 2022-05-09 18:11:37 +0000 |
|---|---|---|
| committer | Dmitry Chagin <dchagin@FreeBSD.org> | 2022-05-09 18:11:37 +0000 |
| commit | b17446281d21311cc4f9d522c5d18337a9f786bc (patch) | |
| tree | be9f11bb39f524873f079443e6f3728373ae6801 | |
| parent | e76857671873f0c9037dcc9c546b490714096c73 (diff) | |
| download | src-b17446281d21311cc4f9d522c5d18337a9f786bc.tar.gz src-b17446281d21311cc4f9d522c5d18337a9f786bc.zip | |
linux(4): Fixed offset miscalculation in the preadv/pwritev syscalls.
MFC after: 2 weeks
| -rw-r--r-- | sys/compat/linux/linux_file.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c index 8926e760fc39..199bed80d92a 100644 --- a/sys/compat/linux/linux_file.c +++ b/sys/compat/linux/linux_file.c @@ -1268,6 +1268,15 @@ linux_pwrite(struct thread *td, struct linux_pwrite_args *uap) return (kern_pwrite(td, uap->fd, uap->buf, uap->nbyte, offset)); } +#define HALF_LONG_BITS ((sizeof(l_long) * NBBY / 2)) + +static inline off_t +pos_from_hilo(unsigned long high, unsigned long low) +{ + + return (((off_t)high << HALF_LONG_BITS) << HALF_LONG_BITS) | low; +} + int linux_preadv(struct thread *td, struct linux_preadv_args *uap) { @@ -1280,8 +1289,7 @@ linux_preadv(struct thread *td, struct linux_preadv_args *uap) * pos_l and pos_h, respectively, contain the * low order and high order 32 bits of offset. */ - offset = (((off_t)uap->pos_h << (sizeof(offset) * 4)) << - (sizeof(offset) * 4)) | uap->pos_l; + offset = pos_from_hilo(uap->pos_h, uap->pos_l); if (offset < 0) return (EINVAL); #ifdef COMPAT_LINUX32 @@ -1308,8 +1316,7 @@ linux_pwritev(struct thread *td, struct linux_pwritev_args *uap) * pos_l and pos_h, respectively, contain the * low order and high order 32 bits of offset. */ - offset = (((off_t)uap->pos_h << (sizeof(offset) * 4)) << - (sizeof(offset) * 4)) | uap->pos_l; + offset = pos_from_hilo(uap->pos_h, uap->pos_l); if (offset < 0) return (EINVAL); #ifdef COMPAT_LINUX32 |