diff options
| author | Jeff Layton <jlayton@poochiereds.net> | 2014-05-09 11:41:54 -0400 |
|---|---|---|
| committer | Jeff Layton <jlayton@poochiereds.net> | 2014-05-09 11:41:54 -0400 |
| commit | cf01f4eef9fe367ec0d85b38dd7214e29e376cdb (patch) | |
| tree | 2222f99e1cbc1979256996d7fa3bb42196acedfc /fs/locks.c | |
| parent | afcf0a2d9289bbe50aab362e6fb2798038815973 (diff) | |
| download | linux-rpi-cf01f4eef9fe367ec0d85b38dd7214e29e376cdb.tar.gz linux-rpi-cf01f4eef9fe367ec0d85b38dd7214e29e376cdb.tar.bz2 linux-rpi-cf01f4eef9fe367ec0d85b38dd7214e29e376cdb.zip | |
locks: only validate the lock vs. f_mode in F_SETLK codepaths
v2: replace missing break in switch statement (as pointed out by Dave
Jones)
commit bce7560d4946 (locks: consolidate checks for compatible
filp->f_mode values in setlk handlers) introduced a regression in the
F_GETLK handler.
flock64_to_posix_lock is a shared codepath between F_GETLK and F_SETLK,
but the f_mode checks should only be applicable to the F_SETLK codepaths
according to POSIX.
Instead of just reverting the patch, add a new function to do this
checking and have the F_SETLK handlers call it.
Cc: Dave Jones <davej@redhat.com>
Reported-and-Tested-by: Reuben Farrelly <reuben@reub.net>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Diffstat (limited to 'fs/locks.c')
| -rw-r--r-- | fs/locks.c | 36 |
1 files changed, 24 insertions, 12 deletions
diff --git a/fs/locks.c b/fs/locks.c index e663aeac579e..e390bd9ae068 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -389,18 +389,6 @@ static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl, fl->fl_ops = NULL; fl->fl_lmops = NULL; - /* Ensure that fl->fl_filp has compatible f_mode */ - switch (l->l_type) { - case F_RDLCK: - if (!(filp->f_mode & FMODE_READ)) - return -EBADF; - break; - case F_WRLCK: - if (!(filp->f_mode & FMODE_WRITE)) - return -EBADF; - break; - } - return assign_type(fl, l->l_type); } @@ -2034,6 +2022,22 @@ static int do_lock_file_wait(struct file *filp, unsigned int cmd, return error; } +/* Ensure that fl->fl_filp has compatible f_mode for F_SETLK calls */ +static int +check_fmode_for_setlk(struct file_lock *fl) +{ + switch (fl->fl_type) { + case F_RDLCK: + if (!(fl->fl_file->f_mode & FMODE_READ)) + return -EBADF; + break; + case F_WRLCK: + if (!(fl->fl_file->f_mode & FMODE_WRITE)) + return -EBADF; + } + return 0; +} + /* Apply the lock described by l to an open file descriptor. * This implements both the F_SETLK and F_SETLKW commands of fcntl(). */ @@ -2071,6 +2075,10 @@ again: if (error) goto out; + error = check_fmode_for_setlk(file_lock); + if (error) + goto out; + /* * If the cmd is requesting file-private locks, then set the * FL_OFDLCK flag and override the owner. @@ -2206,6 +2214,10 @@ again: if (error) goto out; + error = check_fmode_for_setlk(file_lock); + if (error) + goto out; + /* * If the cmd is requesting file-private locks, then set the * FL_OFDLCK flag and override the owner. |