From 46230aa6ea1671690e3e5efa2a961fc0745fe9b5 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Fri, 16 Mar 2007 12:16:27 +0000 Subject: [PATCH] [MIPS] RTLX: Handle copy_*_user return values. Signed-off-by: Ralf Baechle --- arch/mips/kernel/kspd.c | 18 ++++++++++++---- arch/mips/kernel/rtlx.c | 46 +++++++++++++++++++---------------------- include/asm-mips/rtlx.h | 4 ++-- 3 files changed, 37 insertions(+), 31 deletions(-) diff --git a/arch/mips/kernel/kspd.c b/arch/mips/kernel/kspd.c index 241ee7a290..29eadd404f 100644 --- a/arch/mips/kernel/kspd.c +++ b/arch/mips/kernel/kspd.c @@ -191,6 +191,8 @@ void sp_work_handle_request(void) struct mtsp_syscall_generic generic; struct mtsp_syscall_ret ret; struct kspd_notifications *n; + unsigned long written; + mm_segment_t old_fs; struct timeval tv; struct timezone tz; int cmd; @@ -201,7 +203,11 @@ void sp_work_handle_request(void) ret.retval = -1; - if (!rtlx_read(RTLX_CHANNEL_SYSIO, &sc, sizeof(struct mtsp_syscall), 0)) { + old_fs = get_fs(); + set_fs(KERNEL_DS); + + if (!rtlx_read(RTLX_CHANNEL_SYSIO, &sc, sizeof(struct mtsp_syscall))) { + set_fs(old_fs); printk(KERN_ERR "Expected request but nothing to read\n"); return; } @@ -209,7 +215,8 @@ void sp_work_handle_request(void) size = sc.size; if (size) { - if (!rtlx_read(RTLX_CHANNEL_SYSIO, &generic, size, 0)) { + if (!rtlx_read(RTLX_CHANNEL_SYSIO, &generic, size)) { + set_fs(old_fs); printk(KERN_ERR "Expected request but nothing to read\n"); return; } @@ -282,8 +289,11 @@ void sp_work_handle_request(void) if (vpe_getuid(SP_VPE)) sp_setfsuidgid( 0, 0); - if ((rtlx_write(RTLX_CHANNEL_SYSIO, &ret, sizeof(struct mtsp_syscall_ret), 0)) - < sizeof(struct mtsp_syscall_ret)) + old_fs = get_fs(); + set_fs(KERNEL_DS); + written = rtlx_write(RTLX_CHANNEL_SYSIO, &ret, sizeof(ret)); + set_fs(old_fs); + if (written < sizeof(ret)) printk("KSPD: sp_work_handle_request failed to send to SP\n"); } diff --git a/arch/mips/kernel/rtlx.c b/arch/mips/kernel/rtlx.c index 745649e15a..e6e3047151 100644 --- a/arch/mips/kernel/rtlx.c +++ b/arch/mips/kernel/rtlx.c @@ -289,26 +289,11 @@ unsigned int rtlx_write_poll(int index) return write_spacefree(chan->rt_read, chan->rt_write, chan->buffer_size); } -static inline void copy_to(void *dst, void *src, size_t count, int user) -{ - if (user) - copy_to_user(dst, src, count); - else - memcpy(dst, src, count); -} - -static inline void copy_from(void *dst, void *src, size_t count, int user) -{ - if (user) - copy_from_user(dst, src, count); - else - memcpy(dst, src, count); -} - -ssize_t rtlx_read(int index, void *buff, size_t count, int user) +ssize_t rtlx_read(int index, void __user *buff, size_t count, int user) { size_t lx_write, fl = 0L; struct rtlx_channel *lx; + unsigned long failed; if (rtlx == NULL) return -ENOSYS; @@ -327,11 +312,16 @@ ssize_t rtlx_read(int index, void *buff, size_t count, int user) /* then how much from the read pointer onwards */ fl = min(count, (size_t)lx->buffer_size - lx->lx_read); - copy_to(buff, lx->lx_buffer + lx->lx_read, fl, user); + failed = copy_to_user(buff, lx->lx_buffer + lx->lx_read, fl); + if (failed) + goto out; /* and if there is anything left at the beginning of the buffer */ if (count - fl) - copy_to(buff + fl, lx->lx_buffer, count - fl, user); + failed = copy_to_user(buff + fl, lx->lx_buffer, count - fl); + +out: + count -= failed; smp_wmb(); lx->lx_read = (lx->lx_read + count) % lx->buffer_size; @@ -341,7 +331,7 @@ ssize_t rtlx_read(int index, void *buff, size_t count, int user) return count; } -ssize_t rtlx_write(int index, void *buffer, size_t count, int user) +ssize_t rtlx_write(int index, const void __user *buffer, size_t count, int user) { struct rtlx_channel *rt; size_t rt_read; @@ -363,11 +353,17 @@ ssize_t rtlx_write(int index, void *buffer, size_t count, int user) /* first bit from write pointer to the end of the buffer, or count */ fl = min(count, (size_t) rt->buffer_size - rt->rt_write); - copy_from(rt->rt_buffer + rt->rt_write, buffer, fl, user); + failed = copy_from_user(rt->rt_buffer + rt->rt_write, buffer, fl); + if (failed) + goto out; /* if there's any left copy to the beginning of the buffer */ - if (count - fl) - copy_from(rt->rt_buffer, buffer + fl, count - fl, user); + if (count - fl) { + failed = copy_from_user(rt->rt_buffer, buffer + fl, count - fl); + } + +out: + count -= cailed; smp_wmb(); rt->rt_write = (rt->rt_write + count) % rt->buffer_size; @@ -426,7 +422,7 @@ static ssize_t file_read(struct file *file, char __user * buffer, size_t count, return 0; // -EAGAIN makes cat whinge } - return rtlx_read(minor, buffer, count, 1); + return rtlx_read(minor, buffer, count); } static ssize_t file_write(struct file *file, const char __user * buffer, @@ -452,7 +448,7 @@ static ssize_t file_write(struct file *file, const char __user * buffer, return ret; } - return rtlx_write(minor, (void *)buffer, count, 1); + return rtlx_write(minor, buffer, count); } static const struct file_operations rtlx_fops = { diff --git a/include/asm-mips/rtlx.h b/include/asm-mips/rtlx.h index 59162f74a7..65778c890a 100644 --- a/include/asm-mips/rtlx.h +++ b/include/asm-mips/rtlx.h @@ -23,8 +23,8 @@ extern int rtlx_open(int index, int can_sleep); extern int rtlx_release(int index); -extern ssize_t rtlx_read(int index, void *buff, size_t count, int user); -extern ssize_t rtlx_write(int index, void *buffer, size_t count, int user); +extern ssize_t rtlx_read(int index, void __user *buff, size_t count); +extern ssize_t rtlx_write(int index, const void __user *buffer, size_t count); extern unsigned int rtlx_read_poll(int index, int can_sleep); extern unsigned int rtlx_write_poll(int index); -- 2.39.5