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| author | green <green@FreeBSD.org> | 2000-07-27 03:45:18 +0000 |
|---|---|---|
| committer | green <green@FreeBSD.org> | 2000-07-27 03:45:18 +0000 |
| commit | 340f6596474a65328d279d2f5f10a4ef6b5d25e4 (patch) | |
| tree | 1f14a981cfa31e6e51420d366523cb90efceb231 /sys | |
| parent | e68c0dd24922b80c65c9c4120720b13cd27661a4 (diff) | |
| download | FreeBSD-src-340f6596474a65328d279d2f5f10a4ef6b5d25e4.zip FreeBSD-src-340f6596474a65328d279d2f5f10a4ef6b5d25e4.tar.gz | |
Distinguish between whether ktraceing was enabled before an IO
operation or after it. If the ktrace operation was enabled while the
process was blocked doing IO, the race would allow it to pass down
invalid (uninitialized) data and panic later down the call stack.
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/kern/sys_generic.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c index 8e1c4dc..b6ef0a1 100644 --- a/sys/kern/sys_generic.c +++ b/sys/kern/sys_generic.c @@ -155,6 +155,7 @@ dofileread(p, fp, fd, buf, nbyte, offset, flags) #ifdef KTRACE struct iovec ktriov; struct uio ktruio; + int didktr = 0; #endif aiov.iov_base = (caddr_t)buf; @@ -175,6 +176,7 @@ dofileread(p, fp, fd, buf, nbyte, offset, flags) if (KTRPOINT(p, KTR_GENIO)) { ktriov = aiov; ktruio = auio; + didktr = 1; } #endif cnt = nbyte; @@ -184,7 +186,7 @@ dofileread(p, fp, fd, buf, nbyte, offset, flags) error = 0; cnt -= auio.uio_resid; #ifdef KTRACE - if (KTRPOINT(p, KTR_GENIO) && error == 0) { + if (didktr && error == 0) { ktruio.uio_iov = &ktriov; ktruio.uio_resid = cnt; ktrgenio(p->p_tracep, fd, UIO_READ, &ktruio, error); @@ -350,6 +352,7 @@ dofilewrite(p, fp, fd, buf, nbyte, offset, flags) #ifdef KTRACE struct iovec ktriov; struct uio ktruio; + int didktr = 0; #endif aiov.iov_base = (void *)buf; @@ -370,6 +373,7 @@ dofilewrite(p, fp, fd, buf, nbyte, offset, flags) if (KTRPOINT(p, KTR_GENIO)) { ktriov = aiov; ktruio = auio; + didktr = 1; } #endif cnt = nbyte; @@ -382,7 +386,7 @@ dofilewrite(p, fp, fd, buf, nbyte, offset, flags) } cnt -= auio.uio_resid; #ifdef KTRACE - if (KTRPOINT(p, KTR_GENIO) && error == 0) { + if (didktr && error == 0) { ktruio.uio_iov = &ktriov; ktruio.uio_resid = cnt; ktrgenio(p->p_tracep, fd, UIO_WRITE, &ktruio, error); |
