Edward Lionel Blake, now federal prisoner # 79357-079, was sentenced to concurrent 360 month terms of imprisonment for conspiracy to possess with intent to distribute cocaine base and possession with intent to distribute cocaine base. At the time of this conviction and sentence, Blake already was serving undischarged state terms of imprisonment for violation of parole. Blake’s federal sentence was ordered to run concurrently with his undischarged state sentences. Blake appeals the district court’s denial of his 28 U.S.C. § 2241 petition, which sought credit on his federal sentence for the time he spent serving his state sentences prior to the imposition of his federal sentence.

Because Blake received credit against his state sentences for the time he served prior to the imposition of his federal sentence, he cannot receive credit against his federal sentence for that same time. See 18 U.S.C. § 3585(b). Blake also is not entitled to a credit for those times when he was in federal custody pursuant to a writ of habeas corpus ad prosequendam. See United States v. Brown, 753 F.2d 455, 456 (5th Cir. 1985).

To the extent that Blake is challenging the district court’s application of, or failure *161 to apply, U.S.S.G. § 5G1.3, he is challenging the sentence imposed, which is cognizable in a 28 U.S.C. § 2255 motion rather than under 28 U.S.C. § 2241. See Jeffers v. Chandler, 253 F.3d 827, 830 (5th Cir. 2001).

Accordingly, the district court’s judgment is AFFIRMED.