diff options
author | Daniel Borkmann <daniel@iogearbox.net> | 2020-04-28 21:20:20 +0200 |
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committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-04-28 21:23:38 +0200 |
commit | 0b54142e4b09fbf719eb9fc6fe8bcacbd0547ac3 (patch) | |
tree | e65147d1aec55854e854a9a00ec9ac17af193208 /fs/proc | |
parent | 8c1b2bf16d5944cd5c3a8a72e24ed9e22360c1af (diff) | |
parent | 32927393dc1ccd60fb2bdc05b9e8e88753761469 (diff) | |
download | linux-0b54142e4b09fbf719eb9fc6fe8bcacbd0547ac3.tar.bz2 |
Merge branch 'work.sysctl' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull in Christoph Hellwig's series that changes the sysctl's ->proc_handler
methods to take kernel pointers instead. It gets rid of the set_fs address
space overrides used by BPF. As per discussion, pull in the feature branch
into bpf-next as it relates to BPF sysctl progs.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200427071508.GV23230@ZenIV.linux.org.uk/T/
Diffstat (limited to 'fs/proc')
-rw-r--r-- | fs/proc/proc_sysctl.c | 47 |
1 files changed, 29 insertions, 18 deletions
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index b6f5d459b087..df2143e05c57 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -539,13 +539,13 @@ out: return err; } -static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf, +static ssize_t proc_sys_call_handler(struct file *filp, void __user *ubuf, size_t count, loff_t *ppos, int write) { struct inode *inode = file_inode(filp); struct ctl_table_header *head = grab_header(inode); struct ctl_table *table = PROC_I(inode)->sysctl_entry; - void *new_buf = NULL; + void *kbuf; ssize_t error; if (IS_ERR(head)) @@ -564,27 +564,38 @@ static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf, if (!table->proc_handler) goto out; - error = BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, &count, - ppos, &new_buf); + if (write) { + kbuf = memdup_user_nul(ubuf, count); + if (IS_ERR(kbuf)) { + error = PTR_ERR(kbuf); + goto out; + } + } else { + error = -ENOMEM; + kbuf = kzalloc(count, GFP_KERNEL); + if (!kbuf) + goto out; + } + + error = BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, &kbuf, &count, + ppos); if (error) - goto out; + goto out_free_buf; /* careful: calling conventions are nasty here */ - if (new_buf) { - mm_segment_t old_fs; - - old_fs = get_fs(); - set_fs(KERNEL_DS); - error = table->proc_handler(table, write, (void __user *)new_buf, - &count, ppos); - set_fs(old_fs); - kfree(new_buf); - } else { - error = table->proc_handler(table, write, buf, &count, ppos); + error = table->proc_handler(table, write, kbuf, &count, ppos); + if (error) + goto out_free_buf; + + if (!write) { + error = -EFAULT; + if (copy_to_user(ubuf, kbuf, count)) + goto out_free_buf; } - if (!error) - error = count; + error = count; +out_free_buf: + kfree(kbuf); out: sysctl_head_finish(head); |