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| author | Jia-Ju Bai <baijiaju@buaa.edu.cn> | 2023-03-21 16:22:11 +0300 |
|---|---|---|
| committer | Konstantin Komarov <almaz.alexandrovich@paragon-software.com> | 2023-07-02 23:21:23 +0300 |
| commit | 97498cd610c0d030a7bd49a7efad974790661162 (patch) | |
| tree | 2dcbb6f015fccd76a495707baec7c3eefc78fd85 /fs/ntfs3/record.c | |
| parent | c9db0ff04649aa0b45f497183c957fe260f229f6 (diff) | |
| download | linux-97498cd610c0d030a7bd49a7efad974790661162.tar.xz | |
fs: ntfs3: Fix possible null-pointer dereferences in mi_read()
In a previous commit 2681631c2973 ("fs/ntfs3: Add null pointer check to
attr_load_runs_vcn"), ni can be NULL in attr_load_runs_vcn(), and thus it
should be checked before being used.
However, in the call stack of this commit, mft_ni in mi_read() is
aliased with ni in attr_load_runs_vcn(), and it is also used in
mi_read() at two places:
mi_read()
rw_lock = &mft_ni->file.run_lock -> No check
attr_load_runs_vcn(mft_ni, ...)
ni (namely mft_ni) is checked in the previous commit
attr_load_runs_vcn(..., &mft_ni->file.run) -> No check
Thus, to avoid possible null-pointer dereferences, the related checks
should be added.
These bugs are reported by a static analysis tool implemented by myself,
and they are found by extending a known bug fixed in the previous commit.
Thus, they could be theoretical bugs.
Signed-off-by: Jia-Ju Bai <baijiaju@buaa.edu.cn>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Diffstat (limited to 'fs/ntfs3/record.c')
| -rw-r--r-- | fs/ntfs3/record.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ntfs3/record.c b/fs/ntfs3/record.c index 2a281cead2bc..7060f784c2d7 100644 --- a/fs/ntfs3/record.c +++ b/fs/ntfs3/record.c @@ -124,7 +124,7 @@ int mi_read(struct mft_inode *mi, bool is_mft) struct rw_semaphore *rw_lock = NULL; if (is_mounted(sbi)) { - if (!is_mft) { + if (!is_mft && mft_ni) { rw_lock = &mft_ni->file.run_lock; down_read(rw_lock); } @@ -148,7 +148,7 @@ int mi_read(struct mft_inode *mi, bool is_mft) ni_lock(mft_ni); down_write(rw_lock); } - err = attr_load_runs_vcn(mft_ni, ATTR_DATA, NULL, 0, &mft_ni->file.run, + err = attr_load_runs_vcn(mft_ni, ATTR_DATA, NULL, 0, run, vbo >> sbi->cluster_bits); if (rw_lock) { up_write(rw_lock); |